I have a 91 base 4-speed hatch. I need to know what is required to change for the following:
CRX HF 5-speed transmission
Civic DX 5-speed transmission
Civic Si 5-speed transmission

I want to change as little as possible (only the tranny and clutch) and would like to know which one would be the most cost efficient. I don't care so much about performance as I do mileage. I want to cruise at 80 on the freeway at 2500-3000 rpm.

What about changing the ECU?

P.S. Which tranny would allow me to change NOTHING except for the actual tranny while keeping everything else, (clutch, linkage, axles, etc)??

Thanks.

 

you can swap in any DX, HF or Si transmission without changing anything else, as long as the transmission isn't from an 88. HF would be best choice for mileage

 

bump