well here is what my brother wants. he just got this clean 91 crx and wants to get a si for now. the old motor is a DX but we dont know what we need to do the swap. can i still use the dx tranny? what about mounts and wires? please help.

 

you can still use the dx tranny but you will need to do some modifications to your ecu and your wiring harness. check out this site for the wiring/ecu conversion http://hybrid.honda-perf.org/tech/4gdxtozc.html - you should be able to keep the same mounts and everything else for that car. the engines should mount the same. and if you keep the dx tranny, you won't have any problems with the axles. i am not sure if the si axles are the same as the dx.

 

Why not just do the mpfi conversion and put in an Si cam. Otherwise everything else is basically the same. Swapping the whole engine just seems like way too much work for the benefits you would get from it.