i have the 89 350(tbi) with the 2.73 rear end if thats what is in there. im guessing so because everyone has that.

well i wanna goto a bigger gear, 3.73 or a 4.11

i dont know what gears will fit in the rear end that is stock on my car.

please help me on this, my car urges for the jump off the line

3.73 would be nice if it can fit

but 4.11 would also except gas --then also posi would be needed!!!

thanx

 

any gear ratio can fit in the housing you have, the gears are all teh same physical size. it is the jus tnumber of teeth on the ring and pinion gears that is changed.
as far as teh effect on your gas mileage you mention, it will be changed very little on the highway. it is arouidn town that it will be effected, depending on how hard you like to leave lights.
check out this thread for some rpm estimates for different speeds.
https://www.thirdgen.org/techbb2/sho...threadid=80234

later
tim

 

If you over 3.23 gears, you will need a new differential, a series 3 carrier I think it is. I have 3.42 gears, and they are great. 3.73 is about the biggest I would go on a daily driver.

 

you don't "need" a new carrier per se. Aftermarket gear makers have big gears for both carriers.