My 4.0 in my jeep is starting to smoke so its time for a rebuild so why not make it better? I also have a 4.2 motor. What all would i have to do to make a stroker motor out of the 2? I know i have to use the crank out of the 4.2 in the 4.0 motor but do i have to do any machining? Im trying to keep costs to a minimium

 

Yes, you will need to have the block honed (or bored oversize) and most likely you should deck the head.

You'll find much more info on this at jeepstrokers.com and via more google searches