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Unread 06-27-2010, 11:05 AM   #271
vortec23
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I have had alot of things keeping me from driving my jeep.. I just got another donor (92 cherokee laredo ,auto) Im installing the wiring sometime next week .. hopefully it works .. the zj wiring sucks and i cant get the motor to even idle . I'm starting over with the harness from my donor.. (crossing fingers)

Is there anyone looking for quadratrac drivetrain? Rolling chassis (79 golden eagle) I took motor for cj5

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Unread 11-29-2010, 06:23 PM   #272
Colt44
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I have an '83 CJ-7 with the 258. I converted it to MPFI back in 2005. I went with CustomEFIS and seem to be the only person ever to have a good experience with him (but that's another story). We used the intake and injection system from a '91 Cherokee and everything else, including the computer, is off-the-shelf GM. The intake manifold wasn't the best fit, but it did fit, and the exhaust manifold is the original one.

I have been told that switching to the 4.0 head would give as much as 20% increased power and torque, and would be a very straightforward swap, especially since I already have the MPFI up and running. From this thread it seems that any benefit would be mostly at the low to mid range - can anybody tell me more specifically?

Questions:

Is this a simple swap, and is it worth doing?

Will I need to change to a newer exhaust header? (Stock from a YJ, or aftermarket?)

Any downside to doing this? Things to be aware of?
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Unread 12-11-2010, 05:08 PM   #273
nickdestfino
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Colt, the 4.0 is where you pick up all the power. I went from bbd, to a weber, then a cam, then 4.0 head, and finally injection on it. So it was cool to see the difference each upgrade made. The motor now is a 4.2 with close to 300,000 miles on it, comp cam ho 4.0 head, 63mm throttle body, bosch design 3 injector,balancer from hesco, hesco cps bracket and sensor( the CPS hesco sells is A factory automatic tps from the 91-95 wrangler 4.0. The auto is slotted to allow adjustment, the manual is fixed). 91-95 stainless header, weld n bung for o2 sensor in the down pipe, magnaflow cat and muffler. This motor has been bullet proof. I'm runnin 35's with 456's Can do 90 down the freeway if I want. Gas mileage is upper teens if I stay out of the throttle. Idle is around 600 rpm. I shift out at 1500 to 2000 rpm(hurst short throw helps). All this being said, I'm n Sacramento Ca. went through the smog referee where he called it a Frankenstein motor because of the assortment of parts and gave me a sticker, ran it on the dyno with zero emissions registered at 93 4.0 yj standards. Lots of torque, good motor great for wheelin

the only downside to the combination I'd say is the low RPM range 2800 would b redline. @ 2800 it sound like its really doin something though..lol
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Unread 04-04-2011, 12:42 AM   #274
Colt44
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I see my last post in this thread was back in November. At the end of January, on the way home from the last day of duck season, my head gasket gave up the ghost. As long as I had to pull the head, I decided to go ahead and do the 4.0 upgrade. Rather than pulling a head from a donor truck and having it redone, I bought a new one (i.e., remanufactured) from AutoZone, along with new pushrods (the YJ ones are a tad longer, so don't use the CJ rods) and pivots/bridges. I did go to the U-pull-it lot for the valve cover, a stainless exhaust manifold - the one with the accordion sections to prevent cracking - and an exhaust pipe. I also pulled some vacuum plumbing which simplified hooking all that stuff up to the new valve cover, which has different size holes so the old CJ PCV valve and such won't fit. All that cost about $48 and the new parts about $400. Amazingly, everything pretty much bolted up, except for the power steering pump mount, which required a little modification. Oh, and the CJ head bolts are slightly smaller in diameter than the YJ ones, so you have to stay with the CJ bolts. Mine were in good shape so I reused them. The new head weighs 75 pounds bare, which was too heavy for me to manhandle into place, so I braced the hood with a couple of 2x4s and used a block and tackle to lower it right on. My wife handled the rope and I guided it into place. I have posted more details and a photo elsewhere in this forum so search for that if you're interested.

But back to performance. I don't know about the 40 horses claimed by some, but my jeep now starts immediately, runs much stronger and accelerates more briskly than before. There is still plenty of torque down low, but the main increase in power seems to have moved much more into the mid-range. Long story short, I'm very glad that I did this. It was much easier than I expected, and the results are absolutely worth it.

I'd already added MPFI awhile back, and while that brought much better response and reliability, not to mention much easier starting, adding the 4.0 head made a noticeable difference. I was already using a '91 intake manifold, and replacing the CJ exhaust with the YJ one made everything fit properly. (Use 4.0 gaskets for everything.) The YJ stock airbox won't fit, so I used the curved intake tube from a Cherokee with a K&N-style filter at the open end. This not only works well, but looks like it was intended for the application.
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Last edited by Colt44; 04-04-2011 at 12:46 AM.. Reason: more detail
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Unread 06-28-2011, 09:06 PM   #275
twildt
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I have a 78 cj5, 258 i6, 3speed t150, dana 20 TC.

If I do a 4.0 head only i can keep everything and i get more horsepower right? But if i do a 4.0 complete engine swap then i get even more horsepower than just the head swap but have to change out my tranny and TC?


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Unread 07-05-2011, 08:25 PM   #276
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Quote:
Originally Posted by Kman1983 View Post
twildt you don't have to change your tranny and transfercase to do the 4.0 swap. You will either have to modify your bellhousing for a CPS or buy the balancer CPS conversion setup from Hesco. I used a 4.0 fly wheel and modified my CJ bellhousing. Theres pics back on page 19 of this thread that shows how I mounted the CPS on my T176 bellhousing(same as your T150 bellhousing).


What if i were to buy one of these 4.0's? are they better than the remanufactured 4.2's still?

http://www.quadratec.com/Showcases/j...ement_engines/


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Unread 07-22-2011, 12:52 PM   #277
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Hope this is a good place to add / ask questions:
I am "Thinning out" the 1995 Cherokee ODB1 wiring harness at the bulkhead connector. Have already thinned out the 1985 CJ bulkhead connector awaiting inter-connection.

I know the Cherokee connector will be totally thrown away after all wires are cut. Some discarded and some grafted to the CJ bulkhead. Found a few questionable things to pass by the "Experts" here for some direction,
And perhaps some help for those following.
On the 1995 Cherokee Larado bulkhead connector:

A1: Cut & Discard
A2: Cut & Discard
A3: Fused Ignition (green/black) - ??
A4: Cut & Discard
A5: Cut & Discard
A6: Battery Feed (red/black) - ??
A7: Check engine light (black /purple) - run to a new light for engine malfunction
B1: Cut & Discard
B2: Cut & Discard
B3: Cut & Discard
B4: Tach signal (grey/blue) - run to aftermarket tachometer using ?? CJ wire
B5: 4WD switch (black/yellow) - run to speedo 4wd indicator light using ?? CJ wire
B6: Ignition Switch (blue) - run to CJ blue wire
C1: Cut & Discard
C2: Serial buss (2 sets of white/black) - ???
C3: Serial Buss (2 sets of violet/black) - ???
C4: Fuel Pump resistor (green/white) - ??
C5: Back-up lamp feed (black /green) - run to back-up lights on CJ
C6: Oil Pressure Sensor (grey) run to CJ gauge using ?? wire
D1: Headlight switch feed (red/white) - ??
D2: Cut & Discard
D3: empty
D4: Cut & Discard
D5: Cut & Discard
E1: Battery Feed (red/yellow) - ??
E2: Cut & Discard
E3:-empty
E4: Ignition Switch Feed (red) - connect to CJ red wire (main power?)
E5: Cut & Discard
F1: Cut & Discard
F2: Cut & Discard
F3: Coolant Temp Sensor (Violet/yellow) - Run to CJ sensor thru ? wire
F4: Brake Warn Switch (grey/white) - ??
F5: Brake Warn Switch (grey/black) - ??
F6: Cut & Discard
G1: Cut & Discard
G2: Charge indicator - ??
G3: Cut & Discard
G4: Cut & Discard
G5: Cut & Discard
H1: Cut & Discard
H2: Engine Start Relay (Yellow) - ??
H3: Cut & Discard
H4: Cut & Discard
H5: Cut & Discard
H6: Cut & Discard

Thanks!!
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Unread 07-24-2011, 06:41 PM   #278
ymurf
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I am going to be swapping my 4.0 for a 4.0 out of a 94 YJ. You guys that did this swap,What did you do about fuel lines? I have the YJ still and am planning on running an external fuel pump..Should I just unhook the fuel lines where they connect to the hard lines then run new lines to that point on my cj? Also what did you do about the return line?
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Unread 07-25-2011, 06:19 AM   #279
RubyCJ
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Quote:
Originally Posted by ymurf View Post
I am going to be swapping my 4.0 for a 4.0 out of a 94 YJ. You guys that did this swap,What did you do about fuel lines? I have the YJ still and am planning on running an external fuel pump..Should I just unhook the fuel lines where they connect to the hard lines then run new lines to that point on my cj? Also what did you do about the return line?
I assume you are replacing your 4.2 non fuel injected motor on your CJ?
I cut the supply line on the passenger frame rail and installed the external pump with filter. Then ran new steel tubing down the frame and created an arch over the transmission to the drivers side. Atttached it to the frame and ran a hose to the original 4.0 donor supply tubing.
I connected the return line used by the CJ to the return line tubing from the 4.0 donor.
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Unread 07-25-2011, 03:01 PM   #280
ymurf
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Quote:
Originally Posted by RubyCJ View Post
I assume you are replacing your 4.2 non fuel injected motor on your CJ?
I cut the supply line on the passenger frame rail and installed the external pump with filter. Then ran new steel tubing down the frame and created an arch over the transmission to the drivers side. Atttached it to the frame and ran a hose to the original 4.0 donor supply tubing.
I connected the return line used by the CJ to the return line tubing from the 4.0 donor.
Your right,I meant 4.2..You say return line on cj? My CJ doesnt have a return line does it? Where did you run it to?is there a place on the tank of the CJ to hook a return line?
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Unread 07-27-2011, 12:51 PM   #281
RubyCJ
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Quote:
Originally Posted by ymurf View Post
Your right,I meant 4.2..You say return line on cj? My CJ doesnt have a return line does it? Where did you run it to?is there a place on the tank of the CJ to hook a return line?
The CJ return line comes from the in line fuel filter and runs back to the tank.
The tank should have 2 ports on top, in & out.
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Unread 08-27-2011, 01:03 PM   #282
bvrshtr
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basic question - I bought a carbed 4.0 from a guy at work. I thought it was a 258, but once I saw there was no place for a fuel pump, I realized the error in my way. Anyway, my 4.2 is now graveyard dead. Can I just take it out, bolt its flywheel and such to the 4.0, and drop the 4.0 in? The 4.0 does not have fuel injection, and the guy has since given me his external fuel pump. if it helps, the number on the 4.0 is 805MXI7.

Thanks!
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Unread 05-23-2012, 11:02 AM   #283
NelsonATC
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While reading thru this thread, I noticed many references to www.cjoffroad.com, which is now defunct. It seemed like that site had tons of good info on this swap. Does anyone know if that info somehow made it to another site?

Another question if anyone is still watching this thread: Besides the 91-95 Cherokee, what other models have an OBD1 harness that I could thin and use for this swap? Would a Wrangler of the same years work?
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Unread 06-11-2012, 10:20 AM   #284
RubyCJ
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Use a 1996 4.0 with ODB1 electric & Tranny ?

I took a 1996 Cherokee motor with a stick shift and replaced the ODBII intake / fuel rail with one from a 1995 Cherokee with an ODBI .
Used the 1995 Auto tranny with the CPS on the bell housing
Put the whole thing in my 1985 CJ7.
Did the wire harness thing and kept the Map sensor and installed a VSS on the end of the speedo cable.
New plugs, cap, rotor and wires.
Re-set the distributor several times to be sure.

Idles like it has a racing cam in it.
Has great pick-up and runs strong.

Would like not to have the Jeep bounce around at a stop in gear.
Any ideas?
Is the ODBII cam different from the ODBI ?
Thanks
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Unread 04-08-2013, 08:00 PM   #285
supraman1990
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Just thought I would poke in and say.....WOW. I never thought this thread would get like this, all these years later. I don't know where the info from CJ offroad went, as they had the best of everything. If people have specific questions they can PM me again. My jeep I did this to just sold a month or so ago, so I might do another soon, if I can find time to breathe.
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