With an 88 CRX SI in my past, I fully appreciate the thrill our lil cars can belt out...but times have changed and now I'm searchin' for that uber-high mpg car.

Currently I have a 90 CRX DX with stock motor/tranny and am getting up to 42 mpg (its in great shape), but when I'm doing 70-85 on the highway the rpms really jump...and the mpg can dip to 35 (which is still nothing to sneeze at, I realize).

I also have a 90 CRX HF parts car, complete with stock tranny. See where this is heading?

Anyone know any reason why I couldn't put that HF tranny in the DX? I've heard rumors about axle and hub differences, but just completed a search of current and archived threads and didn't see anything pertaining to this exact topic. (Understandably so, as this will turn my moderate 0-60 times into miserable 0-60 times, but its a sacrifice I'm willing to make.) I'm driving up to 400 miles a week...can do the work myself...just don't want to tear things apart, reassemble, hit a formidable snag and have to put it all back the way it was, even though that sounds like a lot of fun...

Thanks for reading.

 

if i were you, id just swap the 5th gear. you are going to absolutely HATE the hf trans. swapping the 5th will drop the RPMs significantly at highway speeds

 

the trans is rediculous..my bro had it in his std hatch for a lil bit with a z6..2nd would go to 90. no power anywhere. he didnt have to switch his hubs or anything.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ryan89crx &raquo;</TD></TR><TR><TD CLASS="quote">...just swap the 5th gear...</TD></TR></TABLE>

Wow. I knew there'd be someone smarter than myself out there. I'll get started doing the homework on how to disassemble, canabalize and reassemble. Thanks for the idea!