The kit discussed below will work, as far as I understand it, with the 258ci and 4.2L displacement 6 cylinder motors used in Jeep CJs and YJs (wranglers) between 1980 and 1990.  Since the same motor was used in some AMC cars (Hornet?, Eagle?, Matador?), the kit should work in those as well.  Of course, don't trust me, call MOPAR. Also available are:

• Installation Instructions
• Hesco Tips

From: jeff reynolds
Date: Mon, 14 Jul 1997 10:47:54 +0100
Subject: Re: 4.2L Rebuild

Randy & Kathy Peterson wrote:
> >> I'm about to rebuild one of the 258 sixes I have. Would appreciate any
> >> info you have RE building a high torque engine. What pistons, cam, lifters
> >> ect did you use ? I saw in your post that you bored it out 60 over.
> >> I immagine that also added to your reasons for using a thick head
> >> gasket ect.
 As I asked above, can you provide any info about a
> high torque engine rebuild ie cam, lifters, pistons ect. I do not
> want to appear to be unappreciative, byt Fel Pro is a gasket maker,
> or so I have believed up untill this time. who made your pistons,
> cam, lifters and what were the part numbers. This may be a little too
> much to ask for. But I might be able to use the info. I'll have my
> block machined (bored, honed to match pistons, decked, aligned bored,
> etc), have the heads reworked, the rods rebuilt and then assemble
> the engine myself at home in the garage. did you have youe engine
> components statically & dynamically balanced (probably not necesary
> for a low rpm, ji torque engine).
> I wanna keep the stiock block, heads ect. I already have the Mopar
> FI to help it perform and meet smog regs for years to come....
*****
Randy and listers,
  Here are the part names and specs:
Pistons, rods: Nylen, .060" over
Rings: Hastings, .060" over
RV cam: Melling, 470 lift, 214 duration
Oil pump: Melling
Lifters: Melling
Timing chain and gear: Melling
Bearings: ACL
gaskets: FelPro
  I did not blueprint, line bore, or balance the engine. It runs very
smoothly and quietly, with more torque all the way down to idle. If I
never get over 3K rpm, it's o.k. What I wanted comes at 900 rpm, foot on
the floor, with the sound of graunching rocks under skid plates and a
steady, throaty exaust, the Jeep pitching in an inclined sea of white
capped rocks, all 4 wheels slowly churning the same speed, sometimes one
in the air, crabbing their way haltingly up a rocky sidehill; my heart
in my throat, my lips dry as dust, my eyes bugged out,..............
  Regards, as always, Jefe

===> Message End <=============================================
Jeeptech is sponsored by off-road.com: http://www.off-road.com
 

------------------------------

From: jeff reynolds
Date: Sat, 19 Jul 1997 01:59:48 +0100
Subject: Jefe's 4.5L , MPI: update

Techsters,
  I have been throwing my usual weekly bags of cash at my CJ-8. Jeanie
wonders with more and more clarity, if this will ever end. 8<[
*New 4WPW's 1 piece axles; greasable tapered bearings, for my rear '20'.
*New updated, 'no shear' Lock Rights. (yeah, we'll see)
*New brakes.
*New rubber boots for the trans and 2 stick T-case
*4 new yokes with the older/better u-bolt style fasteners for the
U-joints.
*New exhaust system to go with my Borla header.
  I had felt a lag in high gear; a kind of resistance. Sure enough, the
Catalitic converter had blown all of its guts into the muffler, which in
turn plugged the muffler. When the guy cut the CAT off, we looked
through and it was totally hollow. The muffler looked like a bag of
microwave popcorn! How did it pass smog? All this happened when I still
had the BBD carb and was constantly backfiring going downhill. I put
2.25" tubing on with the new CAT and free flowing Turbo muffler. Nice
throaty tone, but not loud. It has a much better high end now in the 1st
3 gears, and runs cooler. Each of my 2 previous CATs lasted about 60K
mi.
 
  The 4.5L engine now has about 500 mi., and is picking up more power as
it loosens up. I still don't think it has reached it's potential,
however. I think this has to do with the MPI's distributor advance. My
tipoff here is the fact that I have weaned it down to 87 octane with NO
PINGING WHATEVER. Am I the very 1st with no pinging with 87 octane?  It
seems to be retarded. Yes, I have more power in 1st thru 3rd, but it
seems to electronically flatten out in 4th. The speedo reads about 10%
too fast. After re-reading some of your posts on speedo gears and the
speed sensor, I will get one that spins 10% slower. Oh well, the period
of adjustment continues.
  All in all, the rig is very smooth now, and it does have awesome torque
right off idle . If you have any ideas, give me a buzz.
  Regards, as always, jefe

===> Message End <=============================================

Date: Tue, 22 Jul 1997 18:01:44 +0100
From: jeff reynolds
To: jeep-tech@off-road.com, Jeep-L@knuth.mtsu.edu
Subject: Jefe's MPI/4.5L Chronicles

Listers,
  [I apologize for posting this on both lists, but people on both  have
mailed info and questions to me re this project.]
  My speedo is now (dyno) calibrated with the right gear.[3.55:1 gears,
35" tires] The magic tooth # is 27. The 25t was 8-10% off. YMMV. I felt
more power on the freeway in high (1:1). This was an attempt to fool the
computer into giving me more advance. Better, but still not
satisfied.....
  I talked with Bennie at Hesco. He suggested I go to a dealer and have
their Mopar electronic analyzer (called a DRB-#2) plug into the test
terminal on the new MPI. I still felt that I was not up to power, on the
instinct that I had no ping using 87 octane gas. The "DRB-2" showed the
engine (which the DRB-2 recognized as a '94 4.0L) was burning very
cleanly, but that the long term memory (all 700 mi) said that the fuel
delivery was 30 points over standard: the maximum over spec that the
computer would deliver. Everything else looks good. He said the DRB-2
could retard the timing, but not advance it. Wierd. He said the .060"
overbore would probably require a higher fuel delivery than the stock
injectors could provide. We talked a while longer ( Bill at Pasadena
Jeep (CA) seemed knowlegable) and I explained that in order to keep the
compression ratio down, I had the bare minimum surface milling of the
head and block, and that I used a thick head gasket. He was pretty sure
that these efforts kept the engine from detonating using 87. Simply a
lower compression ratio. That's fine with me. I was after grunt anyway.
  So, I will live with what I have for the time being; which is great!
You just spend so much time and $ on a project that you want to wring
the last drop from every aspect. Let me know if you have other ideas.
  Regards, as always, Jefe

===> Message End <=============================================

------------------------------

From: Randy & Kathy Peterson
Date: Thu, 31 Jul 1997 02:23:25 -0400 (EDT)
Subject: Engines at the Machine shop

I took my well worn stock '82 CJ-7 4.2L (258CI) engine to
the machine shop Monday. Hot tank, boring machine,
CK-10 hoaning machine, valve job , etc are all in process.

But I'm still collecting info about cams and have not been able
to select one for this engine yet. The engine will have a
Mopar FI on it. Moses Ludel recommends the Clifford Research
264-degree duration .444 gross loft cam in his Jeep owners
bible book. But that book was published  about 04/92,
before the Mopar FI was available to the public.

Benny @ HESCO says they have 2 cams for the 258, and he recommends
the one thats good for 6,000 rpm. Larry @ Clifford says they have
special grinds for computer controlled 258 engines, but he did
not know that the Mopar FI was available and Smog legal in CA,
so I'm not sure if they have tested a cam for use with that FI system.

A 4.0L engine cam probably would not work properly in a 4.2 L engine
because the bore and stroke of the 4.0L is much different than the
4.2L engine.

So I am once again looking for input from the learned list readers
on this delicate subject. If you have had a 4.2L engine rebuilt
and are running the Mopar FI on it, I'd like to know the mfg & part
number of the cam in the engine and what you think of it performance.

Goal is low RPM torque (1.5-4K rpm max), smooth idle. Compresion less than
9:1. (60 MPH = about 2400 rpm with the gears and tires I have). Jeep weighs
about 4,000-4500 lb.
 

TIA

Randy Peterson
'82 CJ-7 Jeep

===> Message End <=============================================

Randy- Here is a response I posted to Jeff Reynolds back in May about my
cam

> From: jeff reynolds
> Date: Thu, 29 May 1997 22:41:04
> Subject: Don's  I-6 cam
>
> Barker and Techsters,
>         Here is some cam info I obtained during my 4.2L rebuild:
> Hesco RV cam:  218 lift, 276 duration
> My new RV cam: 214 lift, 270 duration
> Stock AMC cam:     (anyone know?)
> Don's new cam:
> Don, I'm anxious to know your specs big boy, [no, the cam!] 8<).
>
> ....(snip)
>
> jeff

Here is some cam info on what my engine builder put into my '82 258
during the rebuild and my MOPAR MPI conversion. (In addition to normal
quality rebuild, only major work to engine was bored out 0.040 and block
decked to "0".)

Crower Cam grind# 256HPD
intake: duration 256 degrees, lobe lift 0.273, valve lift 0.437
exhaust: duration 264 degrees, lobe lift 0.278, valve life 0.445
overlap: 25 degrees

Stock Cam in '82 258
intake: duration 262 degrees, lobe lift 0.253, valve lift 0.405
exhaust: duration 262 degrees, lobe lift 0.253, valve life 0.405
overlap: 34 degrees

The Crower has the most lift of those mentioned, but just the duration
and the lift don't tell the entire story. For example the exhaust
duration between my Crower cam and the stock are similar, but the Crower
exhaust opens at 38 degrees BBDC while the stock opens at 57 degrees
BBDC.

I'm not a cam man. I relied on my engine builder who picked a cam to not
loose any of the low end, and keep the engine strong up to about 4500
rpm. I expressed my concerns about pinging stories, but he was not
worried with the cam he picked. To appease me he only bumped the
compression ratio to 9:1 rather than the 9.4:1 he originally wanted to
do.

When I dropped the engine back in I installed a borla header and cat
back exhaust system with a new free flow cat. All I can say is that it
is one strong engine! I've not run anything but 92 octane with no
indication of pinging to date.
...

It is now July and the engine is still not showing any signs of pinging!
The engine has proven itself and the original aim of not loosing any low
end and keeping it strong up to 4500 rpm. The cam selection is critical
and it is not as simple as just looking at lift and duration!

I'm running 33's with 4.56 gears and a T-5 transmission so 60 mph is
about 2200 rpm. My builder knew what he was doing when he decked the
engine and picked the cam.  In the back of my head I still wonder what
would have happened if I would have let him have his way and increased
the compression to 9.4:1.

Don
- --
"Donald B. Barker"

===> Message End <=============================================

------------------------------

Date: Wed, 8 Oct 1997 19:03:32 -0800
From: Jeff Reynolds
Subject: Rebuilt engine Bravos and Brickbats

Jeepies,
  Please excuse cross posting of this, but I am stuck and need a
lift.This is directed at you engine GURUS. Delete if you've seen this
already. The history:
  Earlier this year I did a $5K+ rebuild of my '82 CJ-8's 4.2L, I-6
engine. No question, the best part of it was the upgrade to Mopar MPI. I
have no reservations about recommending it to anyone who finds themselves
in the 'BBD Doldrums'. Runs like a top, starts instantly, runs VERY
smoothly, adds 1K more hi end rpms, and my favorite: gobs of torque just
off idle.
  The problem is the engine itself. I never did get the claimed power
or have the posted problems of detonation and the requiremmnt for using 92
octane fuel. The engine feels like it has LESS H.P. than before between
1500-2500 rpm. As a comparison, my 100K mi.+ '89 4.0L XJ, has WAY more H.P.
between 1500-2500 than my 4.5L, and at much less throttle opening. Both MPI
Fuel injection.
  Specs: 4.2L bored out .060" to 4.5L (yes there is plenty of meat to
do that bore to the block)
  Besides all new bearings, pistons, rods, reground crank, and
rebuilt head, I installed a Melling so-called "RV" cam ( 470 lift, 214
duration) thinking that it would further lower the peak torque rpms from
about 1600 rpm with the MPI to 1400 rpm or so.
  The engine rebuilder said there is obviously something wrong with
the MPI. I had it checked on the 'DRB-2', Chrysler's hand held diagnostic
meter and everything looked fine. Plenty of advance-12-13 deg. of advance
at idle and going way up at speed. The only little glitch was the +30 fuel
delivery to the injectors. That's as far as the meter reads on the fuel
delivery.
  For a while I was thinking I put too thick a head gasket on. So I
called the parts supplier for my engine builder. He said that the #8169PT
head gasket is for up to '80 4.2L's and for '86 and up 4.2L's. The #8778PT
is for the '81-85 4.2L's and WILL ONLY FIT those years. Something about the
water leaking into the oil. I now know I have a stock head gasket.
  So today I did a thorough compression test on the cylinders. The
engine has 4K miles since the rebuild. Here are the results: I did ea. cyl.
2 or 3 times, testing after 3 or 4 revs, with all plugs removed and a
screwdriver holding the throttle in the W.O.T postion:
CYl.#   DRY:    OIL:
  #1  121, 124  150, 142
  #2  136, 131  144, 140
  #3  131, 130  130, 130
  #4  128, 126  138, 137
  #5  123, 125  133, 132
  #6  127, 122, 118 133, 130
I talked to Bennie (My Man at Hesco-what a guy!) today. After going through
this litany of woe, he thinks now it may be the valve timing- read cam
shaft timing.
  My question is, if you are still with me, are these compression
readings indicitave of anything? The book says, "140" is the nominal
compression. Except under oil, I have not reached it. What say you?
  Regards, as always, Jefe
 

------------------------------

Date: Wed, 8 Oct 1997 21:34:51 -0700
From: "Gil Meacham"
Subject: Re: Rebuilt engine Bravos and Brickbats

>From your compression readings with and without oil, it appears your rings
have not seated yet.  If they are chrome, you may see them go up as the
engine gets more miles on it.  If the readings do not get better as you put
more miles on it, then your rings are not seating.  The only change between
oil and not is the rings.  Head gasket and valves do not create any
difference between dry and oiled readings.  It is peculiar that you have
lower pressure in #3 with oil than without.  Are you turning the engine
approximately the same number of turns for each reading?

I would run the engine another couple of thousand and retest.  Then compare
to see if you are getting closer to proper pressure.  If it is getting
better, it is just slow seating of the rings.  If it is getting worse, you
may have a problem with scoring the walls or improper alignment of the ring
gaps.

My gut says you will get better readings next time.

Gil
     _____________
    |             |          Gil Meacham
    |             |         "Crispy Critter"
    |_____________|          1977 Jeep CJ-5
  __|\ __________/|__        258 I6  T18a
 /  \|(_)|||||(_)|/  \       AMC20 Detroit
|_____\O ||||| O/_____|      D30 EZ Locker
 ####  | ||||| |  ####
 ####[[[[[[|]]]]]]####
 ####__   ________####
 ####  \_/        ####
 ####             ####
^^^^^^^^^^^^^^^^^^^^^^^

------------------------------

Topic No. 17

Date: Wed, 8 Oct 1997 22:43:13
From: Jeff Reynolds
To: Jeep-L@knuth.mtsu.edu, jeeptech@off-road.com,
Subject: Rebuilt engine Bravos and Brickbats, II

Jeepies,
  [I was in haste trying to get to work on time so my last post was
incomplete.] Here are more clues.
  The engine vacuum is 12 inches at idle, and goes up to about 16
inches at 1200 rpm, no load. Boren thinks this is nominal for an RV cam.
  Complete new exhaust system with Borla S.S. Header, new CAT and
Turbo Muffler, all with new 2 1/4" aluminized tubing. No restriction here.
  Of course, new rings (.060" over), new oil pump, new H2O pump, new
radiator, new hoses, new belt arrangement, new clutch, pressure plate, &
T.O. bearing.
  The MPI comes with many new parts including thermostat (195 deg)
and housing with sensor plug, new Distributor, wires, coil, brackets,
intake manifold, fuel rail, injectors, brain, complete wiring harness, a
half dozen sensors, etc.,
  So again, I am stumped as to why I have less power, mid range than
I had with the BBD's and worn-out version of the engine.
  Thanks for your input.
    Regards, as always, Jefe
 
 

------------------------------

------------------------------

Date: Wed, 22 Oct 1997 14:48:09 -0800
From: Jeff Reynolds
Subject: Jefe's Cam Chronicles

Techies,
  In the ever expanding search for more power out of my rebuilt 4.2L
cum 4.5L ( .060" over, MPI, "RV" cam, Borla, etc.), I have chased down some
flaws. Here is an update.
  1. When I had the engine rebuilt, I specified an "RV" cam to get
more low and mid range torque and power. The term, "RV" gives one the
impression of mild manneredness in the low to mid range with good pulling
power ( "grunt"), and good gas mileage. I find that the term, "RV" doesn't
mean too much. There are several versions of so called, "RV" cams for the
old 4.2L. Hesco has one with 218 lift and 276 duration (at 0), and Clifford
has one with (I think) 216 lift and 264 dur. The mistake I made was not
following up on what and who. This is clearly a result of my not paying
close attention to this aspect of the rebuild. I was told I had a Melling
"RV" cam. Melling doesn't make one. Then things started to unravel.
  2. This morning, I find out, after some days of phonetagging, (
good thing I speak some Spanish) that the cam I now have was a stock cam
ground down so that both lobes (intake and exhaust) were ground to the
lower number's spec. The valves are barely opening! No wonder I have low
power! This cost the rebuilder an extra $15 (!). It's out of there! (or
will be next week)
  3. Today, I called Bennie at Hesco and he recommended their #H-264
cam-(470 lift, 214 duration, 114 centerline, $270), and that I dump the
hi-vol Melling oil pump and go with the stock TRW. He further recommended
that I go with the Cloyes 3 piece roller set; cam gears and chain; #9-3127,
$139. You cannot re-time the stock cam gears as they have a keyway that has
only one setting. The Cloyes can be timed. I ordered the Hesco cam and
Cloyes gear set.
  4. In retrospect, It would have been easier and much cheaper to
have left well enough alone and just replaced the stock cam. I just tried
to squeeze the last drop of power out of the rebuild. [I guess I'm still
trying.] 8<}
  5. I just wasn't paying close enough attention. Somehow the rest of
my life got in the way of the rebuild! Oh well.
  You'll hear how the Hesco cam fares down the road. At this price,
it had better be real good.
    Regards, as always, jefe
 
 

===> Message End <=============================================
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http://www.off-road.com

------------------

Topic No. 14

Date: Thu, 30 Oct 1997 21:41:57 -0500 (EST)
From: Randy & Kathy Peterson 
To: jeep-l@knuth.mtsu.edu
Subject: Re: New cam in the 4.5L?

>Hey

> yeah, how is taht cam? I want one from HESCO too, but the only thing
>is, how hard is it to put in?! Id really like to know what kind of performance
>you gained.

>Mahalo  Alan Chung  90 Cherokee Limited  Honolulu, HI

The HESCO H-264-14B is in there.
I think I have a plugged up cat converter.
So it's not fair to comment on its performanse yet.
But soon I'll check the exhaust for back pressure
and replace te cat if so required.

The Hesco cam goes in the 4.2 L engine like any other
cam. You should changeout the lifters with the cam.
The head has to be removed to change out the lifters
on a 258 engine. The timing cover needs to come off,
usually after the radiator and front grill are removed,
access to the front of the engine is better. Replace
the timing chain & gears while youre in there. Read up
on proper brakein lube for the cam amd proper runin
of the cam so it does not go flat on ya in its first
5 minutes of life.

Randy
'82 CJ-7
rebuilt 258 six
 

-------------------
 

Date: Mon, 24 Nov 1997 08:58:00 -0800
From: Jeff Reynolds
Subject: Jefe's Cam Chronicles, III-"A Multitude of sins"

To: Randy & Kathy Peterson, jeep-tech@off-road.com
From: Jeff Reynolds
Subject: Jefe's Cam Chronicles, III- "A Multitude of Sins"

>At 02:50 PM 10/30/97 -0800, you wrote:
>>Randy,
>>  I just received the [ #H-264-14-B ] cam a few minutes ago from
>>Hesco. You have this same one in your engine already? Maybe I missed this
>>from before. Tell me about your experieces before and after the cam change.
>>Did you punch the bores or add MPI or any other upgrades? Anything I should
>>know? Paul Richards has a Schnieder cam in his 4.5L rebuild and wants to
>>know how it compares.
>>  Regards, as always, Jefe
>>Randy said,
>I finally got my cat problem fixed. The shop installed a new cat right after
>I put the mopar FI in place this last spring. The engine was tired, pinged,
>ect. After a rebuild this fall, the ping went away, but the performance was
>still disappointing. So I had the cat removed. The exhaust pipe on the inlet
>end was shoved up aginst the honeycomb material inside the cat, severely
>restricting flow. Had another cat instaled. Runs much better now.
>
>The Hesco H-264 cam was installed at 0 degrees. Seems to want to start
>performing at about 2k rmp, getting stronger as the engine winds up to 4K. I
>don't usually run it above 3.5k. So I have been thinking about advancing the
>cam timing 5 deg to improve the low end response. Winch off, grill off,
>radiator out, timing chain cover off, ect, ect. Maybe after it quits
>raining, in the spring, I'll do it.
>
>Hope you are happy with your engine and the Hesco H-264
>
>Randy

Randy,
  Sorry I have not replied promptly as I have been out of town.  Some
new and ugly twists have surfaced re: my 4.5L. The Jeep is back at the
rebuilder's to find out why it has no power. He pulled the winch, grill,
radiator, fan and belt, PS pump, AC pump, alternator, pulleys, intake and
exhaust manifolds, F.I., timing gear cover, valve cover, and pan. Armed
with the new Hesco cam H-264-14-B (same as yours) and Cloyes timing gear
and chain from Hesco, the builder agreed to pull the head to see what's
happening. Plenty was happening. @ rebuild plus 5K mi. the engine was still
burning a quart every 500 miles. All the cyls. were leaking, with Cyls. 3
and 5 leaking badly. The rings never seated, or were defective. He has
rehoned the cyls. and replaced the rings, so he pulled the pistons. The cam
bearings (new 5K ago) were fried. I can't tell if they seized or were oil
starved. He will replace. He had the head work checked and found that some
of the valve guides and seals were defective. This may account for the
blow-by in the PCV system. So he sent the head back to the shop and they
did the whole thing again. For the last 2K mi. there has been a sticky
lifter noise for a few seconds on starting in the morning. The crank is
good. It's about the only thing that was good. I think that the
effectivness of the MPI covered, as they say, "A Multitude of Sins". It ran
smoothly regardless of the poor health of the engine. After checking the
Cyl. bores for trueness and spec., he found them within .002" of spec. So
ring gap is ruled out. He can't figure out why so many things have gone
wrong with this rebuild. I did the classic break-in. He has personally
rebuilt hundreds, maybe thousands of engines of all types including scores
of Jeep 6's. This is not rocket science. I guess I'm just the lucky one.
  8<[
  Yesterday he pulled the rest of the engine completely out again to
get to the rear cam bearings. Poor guy, he's loosing, big time on this one.
  The thing I wanted to tell you is that with the Cloyes Cam/chains (
and new hydraulic lifters) there are 3 settings. 0 deg. (the setting you
have), 4 degrees retard for more power above 3K rpm, and the one I will use
which is 4 degrees advanced for more power UNDER 3K rpm. Each setting has a
different shaped slot on the gear. I hope this one will do it. My bro. John
( '73 Bronco, 302-V-8 w / F.I.), advanced his cam  6 degrees (!), and it is
a torque monster for a short stroke Ford V-8, but fades a bit (for a V-8)
after 3K rpm. I have driven it a lot and I would say it has 250 hp. I will
keep you posted.
  My 4.5L symptom was pretty good power above 3K rpm, much less
below. This is symptomatic of a retarded cam timing. It does sound like
your symptom. If you have the 3 position Cloyes already, I think you can
get to and re-time the timing gear w/o taking the whole front end of your
Jeep off.
  I should have the rig back, I hope by Wed.  Oh, please God, let
this be the last of the bad news. I just want to "go hug a rock" in my CJ.
  Regards, as always, Jefe

------------------------------

Date: Thu, 18 Dec 1997 18:26:07 -0800
From: Jeff Reynolds
Subject: RE: Brian's '89 4.0L/NP435/D-300 buildup

SNIP>
Date: Thu, 18 Dec 1997 09:17:27 -0800
From: Brian Smith
Subject: UPDATE Brian's 4.0L conversion

It started out with a good engine pull, tranny and D300 all together, the
Jeep has been striped to a rolling frame with tub still attached and then..

SNIP>

Brian,
  Some of us, who wish we "WOULDA" done this swap, are watching your
progress very carefully. 8<) Keep a good record of all the exigencies, as I
predict there will be a trail of 'copyswapers' following you. The stock
B.H. should work with one more hole at the boss. You will need A.A.'s
adapter from D-300 to NP 435, @ $500+ per copy. As to the wiring, you will
need all of the 'stand alone' F.I. parts, incl. MAP, MAT, Crank, temp, O2
sensors and the CPU. You are right, just take your time with this part.
  I have an '89 XJ with the 4.0L, and like its road manners very
well. These earlier 4.0L's (177 hp) seem to have a slightly better low end
than the H.O.'s (190 hp), but not as good as the venerable 4.2L
gruntmeister (110-115 hp). On the other hand, the H.P. speaks for itself.

  I now have 150 miles on my 4.5L, V.2, MPI, Hesco "264"cam, Cloyes
@+4 deg., Borla, and percieve that it is the stongest Jeep '6' I have ever
driven, all through the range. Bennie at Hesco says I should have 175 hp
and 267 ft. lbs. of torque at 1400 rpm. This doesn't take into account the
Borla header, so the final H.P. may be higher. 8<) [Sadly, 8>( the 4.5L's
immediate pedecessor went south after only 5K mi.] After a few more miles I
will have a report.

  About a half dozen of the 4.2L/4.5L, MPI '6' boys on the list are
contributing to a killer article with many different permutations of
equipment/parts/bores/exhausts/final drives/ and how all this affected the
outcome using MPI.
   "BBD" disease is in its final phase for many jeepers, and this
upgrade is becoming more popular as Jeeps get older, so this will be of
interest to many facing the 'Junk it or fix it' stage.
  Regards, as always, Jefe

------------------------------

Date: Thu, 22 Jan 1998 14:23:30 -0800
From: Steve Piazza
Subject: RE: Mopar's MPI kit

      Damon,

      Unless you install a rev limitor then your 87 shouldn't have one,
I know my 89 doesn't..

      The reason its seems like you lose all your power above three
grand is because of the carb.  I have been playing with certain things
on my engine to see if I can get it to not fall flat on its face above
three grand, Here's What I have tried

      1. Advanced the timing, didn't help
      2. Retarded the Timing, didn't help
      3. Ran hotter plugs, Helped a little bit. I am running splitfires
right now,(before anyone says anything, They were given to me by the
splitfire rep)
      4. K&N air filter, This helped the most, I noticed tremendous
improvement when I switched. I can even tell when it need to be cleaned.
      5. Replaced all the vacuum lines running to the carb, This helped
me out, I had two that were not cracked at all but old and hard, which I
guess caused improper resistance
      6. Ran A hotter thermostat, Big improvement, I had a 170 in there
before, I switch to a 190 and the increase in heat helped allot.
      7. Ran a Hotter coil, I noticed a bit of difference on this one
also.
      8. Keep all heat riser tubes, heat exchange tubes installed. Mine
runs like a dog with out it, In fact I definitely can tell when they
come off.

     Its Still a little sluggish after three grand but not nearly as
bad, I know David Gray of Off-Road.com is running a Jacobs Omni pack on
his ( I believe there is a write up on Off-Road.com about the
improvements on his.

     I have friends that have the 4.0HO and have wheeled with them, I
don't want to start the whole 4.2/4.0 debate again but, The 4.2 is all
lowend, as where the 4.0 starts it torque curve at I think it was 1500
or 2000.

     Well this is getting a little winded for me. If you have any
questions let feel free to email me.

      Steve Piazza
           Steve Piazza
ONE of the WHEELING PIAZZA BROTHERS.
Email: Spiazza@bigfoot.com

Wheeling Piazzas Web Page
http://members.aol.com/MtnMn99/Wheeling-Piazzas.html

WIN A FREE SET OF 5  BFGOODRICH TIRES, EMAIL ME TO FIND OUT HOW, OR look
on
http://www.studio-west.com/gettin-off/calendar/ca4wdcal.html
 
 
 
 
 

> -----Original Message-----
> From: Gentile, Damon (Sta-ENG)
> Sent: Thursday, January 22, 1998 12:30 PM
> To: Jeep-L; Jeep-T
> Subject:  Mopar's MPI kit
>
>
>
>
> I've been thinking about the Mopar MPI kit for my 87 YJ.
> I had the time to compare my carbed 4.2 to a 4.0 HO.
> The 4.2  had gobs more power low on the spectrum. (Mine
> has a rev limiter at 3k- it's pretty flat above that.)
> The 4.0HO had a nice powerband higher up, like 3-4or5k.
> It did seem to have less low end power- could be the
> gearing (4.2=3.55  4.0=3.07; both on 30"s )
>
> If I were to do Mopar's MPI kit on my 4.2, would I lose
> any of the low end power inherent to the 258 ?
> I imagine that I'd gain tons in the upper end.
>
> Can I ask those of you with the MPI kits to let me know
> how you feel the powerband has changed  ?
>
> It's a fuel kit only, no camshaft, right ? Although the
> 4.0 does have a different cam if I'm not mistaken.
>
>
> Thanks,
>  -Damon
>

===> Message End <=============================================
This mailing list is proudly sponsored by Off-Road.com, Inc.
http://www.off-road.com
------------------------------

Date: Thu, 22 Jan 1998 20:37:37 -0600
From: "Louie Belt"
Subject: Re: Mopar MPI

You will not loose your low end torque by installing the Mopar MPI kit.  I
installed it and maintained my low end torque, but gained great highway
performance, better fuel mileage and the ability to idle smoothly no matter
how steep the angle my Jeep is on.  It is definitely the way to go.  I have
an article about it at http://www.netmatter.com/trailrunners in the
technical info section.  It includes a review, along with a complete parts
list and step by step instructions.

Jeepnut

------------------------------

Date: Thu, 22 Jan 1998 21:04:31 -0800
From: Terry Morris
Subject: Re: Mopar's MPI kit

Gentile, Damon (Sta-ENG) wrote:
>
> I've been thinking about the Mopar MPI kit for my 87 YJ.
> I had the time to compare my carbed 4.2 to a 4.0 HO.
> The 4.2  had gobs more power low on the spectrum. (Mine
> has a rev limiter at 3k- it's pretty flat above that.)
> The 4.0HO had a nice powerband higher up, like 3-4or5k.
> It did seem to have less low end power- could be the
> gearing (4.2=3.55  4.0=3.07; both on 30"s )
>
> If I were to do Mopar's MPI kit on my 4.2, would I lose
> any of the low end power inherent to the 258 ?

Actually you would gain about 50% more ft/lbs of torque and
about 45% more hp and about another 500 rpms to the redline.
Differences are OUTSTANDING!!!  You would think you dropped
a V-8 into your YJ with this conversion.  Best thing I ever
did (so far).  Offroad is so much better as well.  I could
go on and on...but suffice it to say it would be worth it
depending on miles on your engine and how long you want to
keep it.

I don't regret converting mine one bit.  If you want more
details, e=mail me offline and we can talk.  A bunch of
us (including Jefe Reynolds) are doing writeups on our
conversions.  You may want to contact Jefe for some brief
insights as well.

> I imagine that I'd gain tons in the upper end.

Power band is smooth and strong all across the spectrum.
Makes the engine really run smooth and strong.

> Can I ask those of you with the MPI kits to let me know
> how you feel the powerband has changed  ?

Tons better!!

>
> It's a fuel kit only, no camshaft, right ? Although the
> 4.0 does have a different cam if I'm not mistaken.

Correct on all counts!!

Later,
Terry Morris
89YJ with Mopar MPFI

Date: Thu, 22 Jan 1998 19:39:23 -0800
From: Jeff Reynolds
Subject: RE: Mopar's MPI kit (lengthy)

*******************************************************************************
 Rebuilding the Jeep 4.2L, I-6 Engine
using the Mopar Multi Point Fuel Injection (MPI)

SEVEN CASE STUDIES

Compiled by 'Jefe'
for
Off-road.com

                HISTORY
  The Jeep 4.2L inline six, gas engine has been around for a long
time. Also called the 258 c.i., it has survived for many years, most of
those under the direction of American Motors. The torquey workhorse was
used in cars, light trucks, and especially Jeeps, finally to be put to rest
as a factory installed item in the 1991 Wrangler. Since its intro by AMC in
the 1960's as a 232 c.i. engine, it was known as a trustworthy powerplant
that could deliver gobs of torque with its long stroke and heavy
crankshaft, exceptable economy, thus  passing through the CAFE requirement
hoop, and be adorned, if not happy with, with a smothering array of
pollution control hang-ons.

        CROSSROADS
  Meanwhile, owners of the venerable 4.2L have, in increasing
numbers, found themselves at a crossroads.  These engines are at the end of
their useful life at 125K to 175K miles and more of hard use. While the
powerplant has many advantages for trail work, the irksome and finicky
Carter BBD carburetor, and balky smog controls hung on most 4.2's have
contributed to an 'motor wanderlust' by many of its owners. Many find
themselves asking, "Should I rebuild it, or transplant another engine?". It
is becoming a point in history where owners must do something: either do
something about the worn out engine, or sell the Jeep. Fortunately, Jeep
has a high loyalty among aficionados, as the qualities of the '70's and
'80's Jeeps are well known, and those who are capable and handy at auto
mechanics, or can afford to have it done, opt to rebuild the powerplant or
do an engine swap.
         OFFSPRING
  It's direct descendant, the 4.0L, I-6, first built under AMC's
management, is arguably the best Jeep engine ever built.  It used the 4.2L
block, with major redesigning of the head with larger intake and exhaust
valves, a new lighter crankshaft, cam timing, and valve lift, all with an
eye to developing more power with less weight, less pollution, and lower
fuel consumption. One of the great achievements of the 4.0L was the
incorporation of Chrysler's Multi point fuel injection, known as MPI, in
1987.  On the aftermarket for about a year now, the kit version, using
mostly off-the-shelf '94 4.0L YJ MPI parts, was developed by Chrysler
engineers with input from people like Lee Hurley of Hesco.
        THE STUDY
  The subjects of this study are seven men who for a variety of
reasons have put MPI on the list of things to add during their rebuilds.
One other added MPI, but has not yet done a rebuild. You will see what they
did, what parts they used in rebuilding, and a subjective 'Impressions'
section by each author, describing how it was before the rebuild, and the
aftermath using MPI, and what they would do differently, if doing it again.
The rebuilds range from bone stock to highly modified with much headwork,
bore and cam changes.

The following is my story. [The next 6 authors and photos will follow.] Jefe.
        CASE ONE
" Long before I owned a 4.2L Jeep , I had performed V-8 swaps on a '49 Jeep
Utility Wagon and a'70 Toyota Land Cruiser FJ-55.  The SBC power was
reliable, cheap, and had been done before, so there was no need to reinvent
the wheel. Advance adapters filled the bill. I was never quite satisfied
with chevy power, as it was a bit too much power above the rock crawling
rpm area I needed, and not enough below 1K rpm, where I did need it.
Additionally, these engines tended to break drive train parts. The balance
between powerplant and drive train was not there. The inline 6, however,
had mongo torque and adequate horsepower, atributes that appealed to me as
a rock crawler. Last year, my trusty 4.2L started, at 126K miles, to blow
massive amounts of oil out the pcv and breather into the intake, soaking my
oil filter, and causing other engine problems. I was never happy with the
BBD carb, and looked for ways to upgrade my '82 CJ-8. For several years I
had been upgrading the drive train, and wanted to retain a relative balance
by rebuilding the 4.2L. Other issues at hand were:
        SMOG
  The state of California in which I live, has very strict laws
regarding what you can, and cannot do with engine transplants, and
alterations to the existing engines. Basically, the laws are; no engine
alteration. Any transplant must be from the same class of vehicle, and all
transplants must be of the year of the vehicle or newer, and retain ALL
factory pollution control devices for that year engine, and pass a state
referee's inspection. This pretty much sealed  my decision in favor of a
rebuild of the existing 4.2L, and an upgrade to Fuel Injection. To my
knowledge, the only CARB exempt F.I. kit is the Mopar MPI. My queries on
Jeep-L cemented my decision to go with MPI. You get a little sticker with
the kit proclaiming: "Mopar Performance Jeep 4.2 MPI Kit installed has been
granted CARB E.O. #D265-7 and is emission exempt in California", and a
serial number for each unit. No more anxiety about smog checks.
        THE KIT
  I ordered my MPI kit from Summit Racing for $1711, including
harmonic balancer, no tax, and shipping. It included a new intake system,
K&N air filter assy., injection system, fuel rail and injectors, with TPS,
MAP, MAT, O2, CP, sensors, distributor, coil, plug wires, complete engine
wiring harness, new fuel pump, fuel filter,; a whole list of add-ons and
replacements., and you lose the old smog pump and dozens of smog circuits
in the process .
          REBUILD NO. ONE
  In the meantime, I contacted a local mechanic and engine rebuilder
with hundreds of rebuilds under his belt, and he started the rebuild. It
was to cost $1700 (at the outset), with:
  Block decked to 0.00 and bored out and honed .060",
    .060" over Nylen pistons/ rods, .060" over Hastings rings
  stock Jeep 4.2L cam, re contoured to the "RV" grind
  Melling high output oil pump, lifters, timing chain and gears
  ACL bearings and Felpro gaskets, new soft plugs
  Head resurfaced, stock valve job/ grind, new springs and guides
  [no blueprint, line bore, head milling to increase compression
ratio, or
  balancing of the engine]

In the process I added:
  New water pump, 4WD Hardware alum. valve cover, radiator, fan
clutch, belt, pulleys, clutch, T.O. bearing, 94 amp alternator, starter,
new starter ring on resurfaced flywheel, Borla S.S. Header and new 2-1/4"
aluminized    exhaust system with cat back and turbo muffler.
Once the engine was rebuilt, I installed the MPI myself without much trial.
        DISAPPOINTMENT
  I drove this combination for 5K miles.  I was never happy with the
power output of the engine. I loved the quick starting and smooth
performance, and the high torque off idle under any circumstances, but the
power on hills seemed down from even the original BBD'd stocker. Then
things started to unravel. I complained enough to the rebuilder that he
tore the engine down again. I was consuming a quart of oil every 500 miles.
We found that the:
  Rings never seated (120-128 compression max), .
  some valve guide seals were leaking and oil was blowing into air
        cleaner.
  Lifter noise on startup for 2-5 seconds. A couple bad lifters.
  Front cam bearing shot
  The head was warped. Complete valve job again, new lifters, guides.
  The so-called "RV" cam was a sham. The valves were only opening .020"
  o.k. for torque, but not enough to make any real power.
  the mileage was not good, and the idle vacuum was 12 inches
        REBUILD NO. TWO
  He didn't have a clue why things went south. I was not a happy
camper. I assured him (and you) that I did the classic break in, and at no
time was the engine ever hot, without water or oil pressure. He rebuilt the
engine again, with me also paying more attention to the job, and him paying
for the rebuild.
Unhappily, I did get to go around more than once. Some things were changed
this time. We substituted the Hesco, H-264-14 cam and Cloyes double roller
timing gear and chains, advanced 4 degrees for more low and middle range
power. These 2 items were about $400. I tried once more to get the McCleod
Industries, 35 lb flywheel (p.n: 465000) to replace the 27 lb. stocker, but
they were again, out of stock. It listed for $333.33. All in all, I was
over $5K into the rebuild and all peripherals. Many of the new internal
parts were in the "good but not best" category.

      DRIVING IMPRESSIONS
  This time is proving to be the charm. I now have a lot more power
for hills and general acceleration than with either previous engine. It is
very responsive. With 4.5L (277 c.i.) of combustable space, the Mopar MPI,
Hesco cam,/cloyes timing gear combo, and free breathing intake/ exhaust, I
do have a LOT more power. At 2000 miles, I'm still waiting for the bearings
to seat well,  to push it much above 3K rpm. I have had it up to about 3500
rpm; it wants to keep going up, and it pulls steadily and very strongly
with no apparent 'flat spot', except maybe down low, just off idle until
900 rpm. The previous 'no-lift' cam had a better, 'off-idle' performance,
but lacked in every other department.  I use much less throttle on the
freeway than before. With my corrected speedo, it zips right up to 80 or 85
mph very quickly with no strain or fuss. At 55 (that's a joke with this new
engine!) I barely have the pedal down. This past weekend the mileage on a
265 mile freeway trip was 19.6 mpg.. With that mileage and a 24 gallon
tank, I can easily expect 450 highway miles on a tank. I was alone, jeep
empty, travelling @55 to 65 mph.  On a recent off-road trip, it sipped fuel
on the trail. The 4.5L has a wad of torque. On an extremely steep and rocky
trail at 8000 feet, in 5.11, first gear high range, the engine pulled very
strongly. Before, I'm sure i would have been in low range. On long and
steep hills, I experimented in high gear, pedal down, lugging the crap out
of it, (1:1 with 3.55's and 35x12.50's)  right down to 25 mph, that's about
900 rpm, and the engine keeps pulling without complaint, with a very even
and subtle drop-off in torque. If the engine continues to seal, as I am
hoping, I think I have found the most appropriate 'hard-core,
rock-crawling' engine I could wish for.  The most important feature of this
set up is that, unlike the bad old BBD days, the engine just ceases to
become a liability. You just drive. It's transparent. A no brainer,
especially off road. Violent jerking, sideways, up or downhill--the engine
just keeps going. I use 89 octane to prevent pinging. My only complaint is
the rough idle. The long term memory of the CPU says that the injectors are
running at +30 on fuel delivery. Above 7000 feet, it idles just fine. I
think it is running lean at idle. Maybe the computer can't adjust to the
over bore, the cam or the higher valve lift. Last week, I reversed the
position of the fuel pump and filter back to pump first. It doesn't make
that sucking sound anymore, but the idle is still rough. I will keep
working on a solution.
  Just so you know, I received no special treatment from Mopar,
Summit, Hesco or anyone on this project, so you can rest assured that my
only agenda is in relating to you my experiences and opinions. I did get
much free advice from Bennie at Hesco. I was out in search of the "Holy
Grail" of torque, and I think I finally found it.
  Would I do it again? I'm not sure I would. One must really be in
the 'project mode' to devote this much time, money and energy to an engine
rebuild, especially twice. A much simpler and cheaper solution would have
been to buy a late model, low mileage , 190 h.p., 4.0L with all
peripherals, and bolt it up. I think it would have cost me half as much as
all the fiddling I did. Yes, it would have less low end torque than the
4.5L, but it would have had as much street power, have a better
head/exhaust design, been easier and cleaner to install, and most
importantly, close enough for the time and money expended."

jefe

'82 CJ-8, 4.5L, MPI, SOA, SO. CAL.

        +========+
        |    jefe|
        [========]
       _/O||||||O\__
       ## o[$$]o  ##
       ##]==O====[##
       ##         ##
 

------------------------------

Date: Sat, 31 Jan 1998 15:53:07 -0800
From: Jeff Reynolds <rgser@westworld.com>
Subject: Attack of the Auto-Meterites

techies,
  FYI, I have started installing all new gages (also spelled gauge)
to go with my new 4.5L, I-6 engine. The factory $2 gages were o.k. when I
had a $2 engine. None of them read very well. Slow and erratic. Here's some
info if you are going the upscale gage route anytime soon. I have the
Laredo Pkg, so in the dash were, from L to R, 2-5/8" clock, (sterring
wheel), 2-5/8" tach, speedo cluster w/ fuel and temp, 2" volt meter, 2" oil
pressure. The tach was the only gage that I thought was worth a hoot.
  I spent some time perusing the AutoMeter cat. and figuring out what
style was the best for my '82, CJ-8. The object was to replace the poor
gages and add any I thought important. In the case of the water temp and
oil pressure gages, I decided on mechanical instead of electric. They seem
to respond more accurately, and the temp.gage will read all the time,
engine on or not. I now wear bifocals, so the "large print" gages were in
order. I settled on (5) 2-5/8" gages, including the tach. By installing the
tach in an easy to read location on top of the steering wheel, I gained
another hole in the dash.  The tach has a black cup and black bezel that
the ga. fits in. The rest of the gages have a black background, white
numbers, red needles, and matching silver-gray bezels. The good news is the
gages on either side of the steering wheel fit the factory holes perfectly.
With the tach installed on the steering wheel, I had to trim the crash pad
back a bit to clear the gage. I started digging into the foam with my
Leatherman (use no. 39734189a), only to find the wiper motor was hidden
behind about a half inch in. A bit shallow on clearance. The adjustable
steering column won't go up to its highest setting. Just finished the
Vacuum gage install where the clock used to go. So from L to R the new
gages are: Vacuum, Tach (over wheel) installed, Water temp., and over to
the right of the cluster, Voltmeter, and Oil pressure (not in yet). These
last 2 will require enlarging the holes from 2" to 2-5/8" in an up
direction. The clearance with the radio precludes enlarging down. I will
need some time to do the other installs as I must drop the A.C. evaporator
down and lower the windshield to get at all the screws to pull the dash
back. These are the gages I settled on:

Auto Meter Vacuum Gage #3482, 2-5/8", 0-30 inches vacuum, 270 sweep, $30.95 from
  Summit Racing. Needle straight up is 16 inches. (Mine idles at 15.)
Auto Meter Tachometer #2890, 2-5/8" Black, Low-Rev (0-4000 rpm), 270 sweep, $75
  I had to set it at the 4 cyl. setting for MPI, I-6.
  Needle stright up is 2000 rpm ( 57 mph for me).
Auto Meter Water Temperature #3432, 2-5/8" mechanical, 120 to 240 degrees, 270
  sweep, $49.95, Summit Racing. Needle straight up is 196 degrees (on
  spec for MPI).
Auto Meter Volt Meter #3592, 8 to 18 volts, $28.95, Summit Racing.
  Needle straight up is 13.2 volts ( on spec for good batt. cond).
Auto Meter Oil Pressure #3421, 2-5/8" mechanical, 0-100 lbs press., 270
  sweep, $27.95, Summit Racing. The pump will go to bypass @ 65 lbs, so
  this goes plenty high enough. (Needle straight up is 52 lbs.)

  Notice that virtually all the gages read at a nominal engine
setting when straight up, making them very easy to read at a glance. This
little report got a bit anal, but I wanted to post it while I was in the
throes of all these numbers and critera.
  regards, as always, jefe

'82 CJ-8, 4.5L, MPI, SOA, SO. CAL.

------------------------------

Date: Sun, 26 Apr 1998 17:45:01 -0700
From: Jeff Reynolds
Subject: MPI pumps/vapor-lock: being more disagreable

Date: Sat, 25 Apr 1998 22:50:40 -0700
From: "Soren Svensson"
Subject: RE: Fuel Injection

> I'd pass on the external pump...you're almost guaranteed to have
> vapor lock
> problems going that route. Either drop in a 15 gallon pre-91' YJ

I have to disagree, almost all high performance vehicles have external fuel
pumps (mounted close to the tank) and they are very reliably. Another thing,
vapor lock is something you get with carburetors, not with fuel injection.

Fuel pressure with fuel injection is usually around 45 psi. Remember to use
high pressure hoses (preferably metal). If you put in an adjustable pressure
regulator, any high pressure fuel pump will do if it can pump enough volume
(there are easy formulas).

Regards
Soren

<SNIP>

Let's see,.... Duff, Jeepskate, Soren,
 I'll have to disagree further. You can have vapor lock with the
MPI. Having had BOTH the factory 4.0L MPI and the 4.5L aftermarket MPI, the
only problem with the externally mounted fuel pump, vis a vi vapor lock is
the:
1. routing of the fuel lines, and
2. the pump/filtration order.

Vapor lock has happened to folks with MPI who have routed their fuel lines
on the SAME side as the exhaust system. Mistake. Some have reported
bubbling fuel (from heat!) in the tank as a result of fuel lines too close
to the exhaust system, and subsequently, vapor-lock. (is that hypenated?)
The filtration should have a sintered brass prefilter before the pump.
Mount pump away from any heat source. Mine is on the crossmember behind the
gas tank (that's 2nd to rearmost crossmember on a CJ-8). I have tried the
order both ways: filter then pump/pump then filter.The first way makes a
sucking noise at idle that I didn't like, but is said to save on the pump.
The second way is the one I have now and it seems fine.

The external fuel pumps to get for Mopar MPI are:

 a.Fuel Pump-electric, Chrysler p.n., P4532709. This is the one that
comes with the kit. It nominally puts out at least 40 lbs pressure.

 b.AC Delco electric fuel pump, p.n., EP:286. This one is my spare,
and puts out more pressure than the above pump (about 90 lbs at stall), but
just makes the return line a bit more active. This one is recommended by
Hesco, and is used by them as a cheaper and more readily available
alternative. No fuel starvation with that pressure!

 c. AirTex #E8248 (rated 60-70 gph, 110-120 psi at stall)
 407 W. Main Street
 Fairfield, IL  62837
 (618) 842-4069

Paul Richards talked with "Craig", who mentioned any grit above 30 microns
is bad for Replacement Fuel Pump. He found this almost by accident; Mopar
had no clue, and Hesco was recommending 'b' above.  Found it in a local
speed shop.
 Duffster, if you want my entire file on this and other MPI issues,
e-mail me direct.
 regards, as always, jefe

'82 CJ-8, 4.5L, MPI, TERALOW, SOA, SO. CAL.

----------------------------------

Date: Sun, 26 Apr 1998 23:11:36 -0700
From: "Gil Meacham"
Subject: Re: Fuel Injection

Soren,

I know several folks with external high pressure pumps, and they all have
experienced problems, from vapor locking to burning up pumps.  If externals
were the way to go, why do all the major manufacturers use internals.  Ford
used to use a low pressure, high volume internal and a high pressure
external pump, and in the late eighties they went to internal pumps.  Vapor
lock is definately a problem with fuel injection as well as carburetors.
Ask Mike Garner and Gene Ferris, among others.  They have both fought
external pumps and vapor lock.

Also, you can not just use any high pressure pump.  On multiport systems
you need a pump that is rated for both the volume and the shutoff pressure
of your EFI.  I have a 5.0 HO, and the rated shutoff is 80-90 lbs pressure
and the flow is rated at 35 gph.  When I searched for the proper pump
(after having problems with another high pressure pump) I found that there
are pumps rated all the way from 16 lbs shutoff to 120 lbs.  While your
regulator on the fuel rail will ultimately control the rail pressure, it is
important the pump is rated to work with the regulator.  Otherwise, it may
be operating above it's rating, and it will probably fail prematurely.  I
beliefe a 4.0L is rated for 40 lb shutoff and 25 gph, but I looked at so
many stats when I got my pump I would not guarantee it.

As far as the easiest way to put the right pump in for a 4.0, if you get
the sending unit/pump combination from a 4.0 YJ, it will probably fit in
the scrambler tank.  They both use the 3" O ring sealed sending unit, and I
tried on in a CJ tank and it appeared to be the right depth.  I am sure
that a sending unit from a '90 2.5L 4 cylinder will fit the CJ tank, but
the pump is only a 16 psi, 25 gph pump.  I replaced the 2.5L pump with one
from a mid eighties Ford for my application, and it took about 20 minutes
to modify the sending unit to accept the Ford pump.  They are all very
similar.  I would try to use the 4.0L sending unit in the scrambler tank
before buying a wrangler tank and having to change filler necks, etc.

For my tank, I used the one from the '90 2.5L YJ.  I decided to get fancy
and change to a left side TJ filler neck.  It was a major undertacking.
Just converting all of the different sized filler neck and tubes was a lot
of trial and error.

Good Luck, Kurt!

Gil Meacham

1977 CJ5 5.0L EFI Ford, NP235 D300

> From: Soren Svensson
> To: jeeptech
> Subject: RE: Fuel Injection
> Date: Saturday, April 25, 1998 10:50 PM
>
>
>
> > I'd pass on the external pump...you're almost guaranteed to have
> > vapor lock
> > problems going that route. Either drop in a 15 gallon pre-91' YJ
>
> I have to disagree, almost all high performance vehicles have external fuel
> pumps (mounted close to the tank) and they are very reliably. Another thing,
> vapor lock is something you get with carburetors, not with fuel injection.
>
> Fuel pressure with fuel injection is usually around 45 psi. Remember to use
> high pressure hoses (preferably metal). If you put in an adjustable pressure
> regulator, any high pressure fuel pump will do if it can pump enough volume
> (there are easy formulas).
>
> Regards
> Soren
>
>
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===> Message End <====================================================== List, (pass on this if you have no interest in smogging the Mopar MPI) THE GOOD: It was my good fortune to stumble on the MPI system a couple of years ago (because the Carter BBD WAS stumbling!), and wind up installing it on my CJ thinking it was truly "EMISSIONS EXEMPT IN THE STATE OF CA" ( the state in which i reside), as the accompanying sticker pronounces. I blithly charged into a campaign to change and improve everything on my 4.2L Jeep engine to make it a TORQUE MONSTER for crawling that Sierra Granite I so love. This included changing to a Hesco .470 lift camshaft, boring the cylinders and adding .060" over pistons, installing the Cloyes 2x roller, 2x chain timing gear, advanced 4 degrees for more low and mid range torque, and adding a Borla header for freer breathing above 3K rpm. I was sucessful in winding up with a 4.4L powerplant with exceptional grunt from just above idle on up; no flat spots; with peak torque at maybe 1600 rpm. that would not stall or balk under any circumstances (straight up, straight down, sideways, etc.). I was just tickled about the performance of the engine, especially off-road. It will travel down the Freeway at 80 or 85 all day with the pedal partially down, getting 14 mpg, and 20mpg @ 60 mph with the pedal barely down. In the back of my mind was a little voice telling me that trouble was ahead in terms of 'smogging' the beast, even with the so-called exemption. THE BAD: Well, the hammer finally came down. The fact is, "emissions exempt" means the smog laws proclaiming one must not change or alter ANY emissions control equipment, MAY be breached, in this case (Mopar MPI) by Executive Order #D265-7 of the California Air Resources Board. It means that you are allowed to make the changes prescribed by the instructions for the MPI aftermarket fuel injection kit. It DOES NOT mean that you don't have to pass the smog test for that year ('82 in my case), in fact you MUST pass an even stiffer smog test of the '94 California model 4.0L Jeep Wrangler engine. I was really starting to sweat now what with all the changes I made. THE UGLY: It was with a heavy heart that I spent the day trying to 'smog' my '82 CJ-8. The first thing I did was replace the catalytic converter, as it was in poor condition after only 5K miles. I think I killed it on Sierra Granite. Then I went to a liberal (as in not too strict) smog inspector, and he said he didn't know anything about this exemption stuff, and besides you need a preheater for the air cleaner (on a K&N?) and, " that header will never pass the visual", etc. I went home dejected and remembered I had an add for a guy who had a CJ exhaust manifold for sale ($30) and phoned him, expecting I would have to retrofit a cast iron manifold. He said he still had it and I went directly over to see it. He said his father had put the MPI on his CJ and didn't need the manifold as he went to the Borla Header. I asked him if he had the engine smogged and he said, "yes, down at Pasadena Chrys/Jeep". "It passed with the header?", asked I, and he said, "Yep, just last week." I passed on the manifold and went directly down to Pasadena Jeep. They said they could get right on it. 3 hrs. later they started to 'smog' it. The new, "SMOG II" (since July 8th) is very tough and costs around $150. It is on a dyno, and many more tests are performed than previously*. The technician said that many if not most of the BBD Carbed CJ's do not pass, and become "Gross Poluters" and must be seen by a referee every year. What a hastle. I paid for a 'pretest inspection' to make sure everthing was o.k. It was with fear and trepidation that I was allowed to watch the proceedings for the final testing. HERE COME DA JUDGE: The pretest inspection failed--only on one account. The gas cap. There is a test for the gas cap, and it did't pass. The technician said most of the CJ gas caps do not pass, even new ones right off the shelf. So I had to bum a ride down to Pep Boys to get another gas cap (as the Jeep place had none in stock). He ran the test for keeps this time, and the engine passed with flying colors. (whew!) He said that my engine ran cleaner than most of the 4.0L factory engines he has tested. With all the alterations, I was surprised. Here are some of the specs.:

test rpm %CO2 %O2 HC-(PPM)----------- CO%------------- measure measure measure max average meas max ave meas 15mph 1663 15.1 0.3 240 53 21 1.73 0.28 0.00 25mph 1634 15.0 0.2 143 40 12 1.53 0.23 0.00 NO (PPM)---------------------------- max average measure result 15mph 3690 442 448 PASS 25mph 3430 563 512 PASS

*The other tests were: PCV, spark controls, wiring to sensors, fuel cap integrity test, fuel evaporative controls, fuel injection, vacuum lines sensors/switches, fuel cap test, catalytic converter, oxygent sensor, other related emissions components, ignition timing (NA). So the long and short of it is: 1. MPI may be "emissions exempt" but it is not exempt from emissions testing as I was led to believe. 2. Be sure to have everything pass the visual. 3. You are taking a chance if you do much "tinkering" with the engine internals. Feel free to e-mail me direct with your experiences with smogging the MPI as I'm keeping track. Several have e-mailed me already with their harrowing experiences. regards, as always, jefe jefe@rubicon.off-road.com http://www.off-road.com/~jefe Jeff Reynolds '82 CJ-8, 4.4L, MPI, TERALOW, SOA, SO. CAL.