intake cj/yj
dalefan88
Crazy Sr. Respected Jeeper
can you use a intake off of a yj AMC 258 i6 / 4.2l and put it on a CJ4 .2. im looking for a intake with smaller flanges to go with my hedman header.
intake cj/yj
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elwood blues
Always Off-Roading Jeeper
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IIRC Dale, the 1981 and newer AMC 258 i6 / 4.2l intakes and the 1980 and older intakes are not the same. The newer ones have the heat element and coolant flow through them and the older one's don't. That's why Offenhauser and Clifford make them for the different years.
Now I remember reading somewhere that you can make one of the newer ones fit on your older head by grinding down one of the alignment pins, the one in the back of the engine. I don't remember where now, but I'll see if I can dig anything up for you
Now I remember reading somewhere that you can make one of the newer ones fit on your older head by grinding down one of the alignment pins, the one in the back of the engine. I don't remember where now, but I'll see if I can dig anything up for you
elwood blues
Always Off-Roading Jeeper
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- 1978 CJ7 4.2L Comp Cam & valve train, MC2100 carb, MSD ignition, Dana 30 front, T18 trans, Dana 20 txfr, AMC 20 rear.
And the other big difference I almost forgot about, the '80 and older intake and exhaust manifold bolted together, the '81 and newer ones didn't. I'm still looking for where that info about grinding the rear alignment stud down, but for the life of me I can't find it.
Rescue Diver
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- 1979 CJ-7 with a fiberglass body and 1982 wide track axles, 258 I-6 with a 1995 4.0 head, HEI distributor, Motorcraft 2100 Carb, T-18 wide ratio tranny, Super Lift Springs and 33s, a 1997 BMW 328i, and a 2010 REDLINE CONQUEST TEAM Cyclocross Bike. :)
The pre and post 1981 intake and exhausts can be swapped as a set to either head(pre or post 1981) as far as I know. The 1981 and newer AMC 258 i6 / 4.2l intake only requires slight grinding where the dowel pins go if you're bolting it on a 1991 or newer 4.0 head with the raised intake ports because the intake manifold mounts on top of the dowel pins instead of the dowels going through the holes.
I don't think there is any difference in the 1981-1985 CJ AMC 258 i6 / 4.2l intake and the late 80's YJ carb intake. I haven't seen them side by side, but I read that they stayed the same until Chrysler went to fuel injection.
Is your current intake made of cast iron or aluminum? If you're running the stock 1979 cast iron intake, go find an 81 or newer Cj or YJ aluminum one and it should work with your header flanges.
I don't think there is any difference in the 1981-1985 CJ AMC 258 i6 / 4.2l intake and the late 80's YJ carb intake. I haven't seen them side by side, but I read that they stayed the same until Chrysler went to fuel injection.
Is your current intake made of cast iron or aluminum? If you're running the stock 1979 cast iron intake, go find an 81 or newer Cj or YJ aluminum one and it should work with your header flanges.
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dalefan88
Crazy Sr. Respected Jeeper
thanks guys thats what i needed to know. i have the stock castiron intake on the stock AMC 258 i6 / 4.2l head.