4.0 head thoughts

[Rippin]

Ive been tossing around motor ideas lately, weighing price vs performance vs reliability, and i just keep coming back to a rebuilt AMC 258 i6 / 4.2l bottom end with an odessa head. Thats my best solution because i keep my T-5 and Dana 300 , its got better performance than stock, and its cheaper than buying and rebuilding a v8.

Now my questions. Ive searched and couldnt find clear answers to these. #1 Will my AMC 258 i6 / 4.2l intake manifold work? Ill be keeping the carb so f.i. isnt an issue. #2 will i need 4.0 lifters rods and rockers or will the AMC 258 i6 / 4.2l ones work? #3 head bolts. Ive seen it discussed before, but i couldnt find it. What size and length? Part #s would be fantastic

Thanks guys!

 

[73CJ]

#1 mine would not fit. Some say they will. Go figure.

#2 push rods come in several lengths. If you deck the block and/ or the head that can also change things. Most important is to get the lifter preload correct. That is really what determines the length. AMC 258 i6 / 4.2l lifters are the same.
1983-96 4 CYL 2.5L
1974-90 6 CYL AMC 232 i6 or AMC 258 i6 / 4.2l
1987-96 6 CYL 4.0L
1971-93 8 CYL AMC

#3. Also can vary. Check out this site.
Jeep 4.0 4.2 258 Cylinder head bolts / fasteners

Double think the FI. You will be amazed how easy it is swapping on a 4.0 head.

 

[BrockGrimes]

There are others in here but see post #15:
http://www.jeep-cj.com/forums/f99/useful-info-thought-id-share-665/

I have the 2 PDF's for Tim Weaver if you'd like them emailed over PM me.
Also trying to resolve that link.