4.0L head onto 1990 XJ Limited

Does anyone know if a HO head can be placed on a nonHO block? What mods have to follow?

The engine is a 1990

I think it will but I'm not sure. Somebody told me the only difference between the HO4.0 and the Renix4.0 is the intake/exhaust manifold, whethere that's true or not's a different thing.

I was reading a page online that mentioned a difference between the HO and no HO heads and manifolds. That is what prompted my question. It would be interesting to find out if it is feasibly, but more importantly pratical. The article spoke of a differnce in port design. I don't know enough about it to relay it well. It would be great to have that possibility. I have been stuck out here in VA and need a "project".

The H.O head flows better, and the H.O also has a completly different computer system. There are also some differences in the Fuel rail, injectors, and I think Fuel pump. It is possible to convert a Renix over to a H.O head, but you would probably be wise to change a few other things over, like the injectors (higher flow to match the increase air intake flow) and I think you have to switch over to H.O temp sensor (the renix has it in the head and the HO has it on the thermostat housing). The swap is possible though