I've been having a few issues with my rearend. I'm not really building a race car... but am trying to make a fun fast sports car that can keep up with most modern sportscars made today. I was palnning on replacing the rear girdle with one of those Summit ones for more strength and figured a new set of gears would be a good idea too. I'm not sure what I have in there already and i know a set of 3.73 are over-kill so I"d like to hear a few suggestions or experience with different ratio gears...

The car is an automatice 89 Formula 350TPI the only mods are the ones listed. Thanks for any advice you can throw my way.

 

humm alot of people say that the 3.73 are over kill for tpi... so i think if you got the 3.42's it will help alot off the line..

 

I just know that I'm probably a few burn outs or hard launches away from chipping teeth off my factory gear that are in there now. They do have like over 160,000 miles on them and no dought the prvious owners tore the hell out of the car in it's earlier years...

any suggestions... or just replace the 3.42's that are in there now?

Any brand names you people can steer me towards?

 

The Rear you have on your car is in MOST cases the BW 9-Bolt
and that is a whole new ball game for parts. Check your rear axle
cover for the number of bolts (9) or your RPO codes. You probably have 2:77 gears which were the most common with a 350 and a auto tranny.