Is it amc 4.0 or wrangler 4.0?
mattp1788
Jeeper
I am looking at doing the 4.0 head swap on my AMC 258 i6 / 4.2l but not for sure if it is meaning putting the amc 4.0 on or the wrangler 4.0 with fuel injection?
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Is it amc 4.0 or wrangler 4.0?
- Thread starter mattp1788
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All the 4.0 were fuel injected. The best head came on the High output 4.0 they came in Wranglers, Cherokees, and some of the Grand Cherokees not positive on the years but I think its 91-96.
csuengr
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The first 4.0 was used in the 1987 XJ. AMC basically added two cylinders to the AMC 2.5. The 4.0 was used in the GC untill 2004 and the TJ till end of production. The 4.0 HO came out in 1990.
mattp1788
Jeeper
Ok so would it be better to upgrade the AMC 258 i6 / 4.2l or just drop in a ho 4.0?
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- 84 cj7, 91 cherokee, 78 chevy 3500 pu, 78 CJ7
I plan on going with the 4.0. I've had three of them in Cherokees and love them its hard to beat fuel injection.
Its going to be more difficult to swap in the 4.0 motor. It wont mate up to your current Transmission and you will need to use the wiring harness from the donor jeep. Read this thread and see what you think.
http://www.jeep-cj.com/forums/f2/258-4-0-head-swap-results-8500/?highlight=head+swap
http://www.jeep-cj.com/forums/f2/258-4-0-head-swap-results-8500/?highlight=head+swap
- Posts
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- Frederick colorado
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- 84 cj7, 91 cherokee, 78 chevy 3500 pu, 78 CJ7
This is the best wright up I have seen and he did use the stock T-5 Transmission .
http://www.google.com/url?sa=t&rct=...cddfC9fy2yUnxJZIr2ig5Ww&bvm=bv.45960087,d.aWc
http://www.google.com/url?sa=t&rct=...cddfC9fy2yUnxJZIr2ig5Ww&bvm=bv.45960087,d.aWc
csuengr
Senior Jeeper
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- Loveland, CO
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- 1980 CJ-7 LT1 TF727 NP231-D300 Waggy D44's ARB's 35" tires
The 4.0 will bolt right up to his current Transmission . The only hard part is dealing with the crank position sensor. He would have to move it to the front.
Sorry for the confusion there , I was wrong. I thought the bellhousings were different. I had the 4.0 in my 88 XJ and it was a great engine. Now you guys have me thinking about it for myself. 
- Posts
- 11,552
- Media
- 57
- Thanks
- 11
- Location
- Frederick colorado
- Vehicle(s)
- 84 cj7, 91 cherokee, 78 chevy 3500 pu, 78 CJ7
Your welcomei had the 4.0 in my 88 xj and it was a great engine. Now you guys have me thinking about it for myself.