[2.5rs4ever]

manual to manual



if it directly replaced the 2.5rs's transmission, will it change the RPM vs MPH?

since the 2.5rs has pretty high RPM while cruising at 70mph+ which is bad for the engine.

will the wrx transmission change the RPM vs MPH ratio>? hence better gas mileage while cruising at 70mph+ because of lower rpm....

 

[kainam00]

You will have to change the rear diff to match the transmission, or the engine will try to spin the front and rear wheels with different speeds.

At 70+ mph you're at what, 3500rpm? That's not that bad for the engine... most of the people here with 98-01 RS's (which have even shorter gearing) have well over 100k on their cars with plenty of 70+ mph driving. I wouldn't worry about it... a new transmission/rear diff will cost you as much as a new engine, so it is definitely not worth the trouble.

 

[ZeroPunk]

I know that the 06-07 wrx transmission has a higher 5th gear then our RS transmission... but that's all I know (friend has one).