Um, no, a 4.2 crank with 4.2 connecting rods will net you a minimum of .5 more liters. If you want more than that, than you can get the head ported, polished, block bored .060 over and/or if you have REALLY deep pockets get your 4.2 crank offset ground. It is possible to to turn a 4.0l into a 5.0, but that is $money$. The typical jeep stroker is around 4.5 4.6 liters. Just as an FYI, my stroker would have cost me $2,400 total, out the door, running in my truck, no short cuts, machine, parts, doodads, everthing. I was $300 short and the rest is history. . . :cry:
I will admit i know nothing about the mini stroker stuff, but i would like to think i know a thing or two about the bigger stroker.
if you want to know the facts about strokers these two sites have more information than you will ever need.
http://jeep4.0performance.4mg.com/stroker.html
http://www.jeepstrokers.com/forum/