i have a 87 sport coupe with a 305 with a aftermarket intake manifold and a "open exaust" off the y- pipe. My car also has a 2500 torque converter shift kit transcooler vette servo and a couple of other minor mods. currently i believe i have a 2.73 rearend {one tire fryer}. i still want some gas millage but i know my rear end is holding me back. what should i swap it to? would a 373 be to much with my upgraded torque converter? my engine doesnt turn that high of rpms. so i dont want to "rev out" to quick. i havent been to the track yet but after my rear swap im shooting for high 13's --- help me out guys, thanks ----- people have been telling me 373 or 342 so im torn

 

If you drive significant highway miles, I recommend the 3.42's.
I have 3.73's and I really think they're too much for a stockish engine.

 

Depends you said your motor doesn't turn high rpms. So if you mean that your totally out of the power band by 5500rpm I would go with the 3.42s. 3rd gear is your 1:1 and you don't want the tranny shifting to overdrive on the strip. I'm running mid 13s now with my T5 and 3.42s but thats because I can't get off the line and have really crappy 60 foot times. So it depends you have a lot less motor then I do. So with out spray I don't think your gonna hit 13s. Either which way if your going to do mostly street driving I would probably go with 3.42s since you have the fatter converter.

 

lol i hope i can hit 13s i whomped my buddies nova on the street and he just went to the track and ran a 14.4