2.5L to 4.6L swap

[akadeutsch]

I am in a jeep club at work and a guy here wants to swap his 2.5L for a built 4.6L stroker in his 94 YJ. I am helping him with his build because I think it is fun. The first thing that I want to know is what year 4.0 should I look to build? Does it have to be a 94 4.0? I know that we all switched to OBDII in 96. Does this mean I have to use a pre OBDII engine?

[SilverXJ]

Any year except 99+ WJ and 00+ TJ should work fine. OBD II vs. OBD I has nothing to do with the block. OBD I did have a coolant temp sensor in the head that most OBD II heads did not have, but that is a minor issue.

[akadeutsch]

Rad!!! Thanks Silver!!! Can I ask why the 99+ wj block is different? I only ask because I drive (or at least I did before I pulled the motor) a 00 WJ. In your opinion what block is best to build for a 94 YJ?