like the title says, can a 98 civic cx's tranny hook up with the 91 crx si's engine? let me know quickly please, and a little explaination perhaps on the side will be great, thank you.

 

The short answer: To the engine, yes. To the car, no.

The long answer: Even if you got the CX tranny for free, you're going to spend money/time customizing to make it work. Plus, the gearing sucks for performance...its like worse then L3 DX, but not quite as bad as HF ratios. You're far better off spending $200 on a decent used L3 Si transmission then trying to make a free CX tranny work. And if you're paying for a CX tranny...its a really, really bad idea.