trying to figure out my factory gear ratio its an 89 gt convertible. im going turbo and thinkin 3:55's are the best gear for turbo...any thoughts on this let me know plz! thx.

 

Thers a tag on the rear cover,scope that.

 

jack it up mark the inside of a tire , the ground and the drive shaft and count or open your diff and count the teeth on the gear. unless u bought it new there is no assurance of whats in it. OR post your rpm at 60 mph in 4th gear os its a maunal or 3rd if its an auto and somone will convert it for you. Be aware all physical gear ratios are based on a 28in tire

 

^^ what he said

Well I can confirm that they didnt come from the factory with 3.55's lol

But like badlatitude said its hard to say...an 89 might have been changed out by a previous owner.

But if you still interested in what the "stock" gear is...is it auto or manual?

 

tag says..

S215A
2L73 88 0M17

 

your car likely came with 2.73s. 3.55 is a good choice for a boosted street car.

 

its an auto, and i know it didnt come with 355's, i wanted to know if that was a good gear choice to go with for turbo application...

 

2.73 according to tag.

Turbos spool because of load, and that lower stock gear is perfect in my experience.

 

^ lol.....yea 2.73s

 

cool i figured after i yanked the tag and i saw the 2L73...lol thanks for the help guys!