hello. I'm am the not so proud owner of a 1996 grand cherokee with it's engine in the back seat. It is the original engine and was taken out for a rebuild. How hard would it be to put a jeep 4.2 crank in it and stroke it out. Would i be able to use the pistons and the rods out of the 4.0? Would this affect things like the fuel/air ratio in the cylinders or emissions testing? also, i have read that in 1996 jeep redesigned the engine to be quieter, smoother, and less harsh. would i still have these benifites. sorry about all the questions but i wantto do this right the first time for time and financial reasons. This is the only thing i will have to tow with.
thanks

 

You can use the 4.0 pistons but I think you have to use the 4.2 rods. I may be mistaken though.
And Welcome to CF.

Note: I found this info. >>->https://www.cherokeeforum.com/f51/strokers-15710/

 

thanks. i'm still doing research but the main thing i want to avoid is computer programing problems and spending tons on machine work. i've made plenty of sb chevys and chrysler 2.5's but never a I6. i have to pass the e-check.

 

From what I've read you shouldn't have any problems.