oh and one more question

[addotta]

What is the liklihood that a 97 4.0 would match up to a 88 Xj for an engine swap?

[XJNick]

Hi,

I'm not too sure about what mounting problems, if any you may encounter. My guess would be that the clutch slave cylinder & throw-out bearing will need to be modified, since I believe 97s use an external slave cylinder. If you have an Auto transmission it could get more complicated.

One thing to consider though is that the 1997 motor will require some electrical system modifications because it uses the current OBD-II system instead of the old OBD-I style system.

The only difference is the number of sensors, how picky the PCM (computer) is about them, and the fact that the wiring harnesses will have to be spliced to match. For example you'll have to install a downstream 02 sensor into the exhaust pipe (in addition to the one you already have.)

So your best bet would be to get the engine, Powertrain Control Module, sensors, and all wiring harnesses with the engine so they match. Then the fun begins with wire splicing. But It shouldn't be too bad

-Nick