Just curious. I replaced the factory 2.77 rear with a 3.27 rear and just wanna make sure the car doesn't still think it has 2.77's when it is really running on 3.27's. If that makes any sense. Thanks fellas

Will

 

hey will -
if your still curious . . . yes, the car will think it's still running 2.77's and nothing you can do with computer tuning will help that. Your speedo will read approx. 118% of actual speed. The only way to have it read correctly is to change the driven and drive gears in the trans tailshaft.

 

Yeah I knew that. I was thinking more along the lines of shift points but then I remembered these trannies are still hydraulic rather than computer controlled.

Do you know where I can get the correct drive and drivens for my application? I was really disappointed when I ordered my tranny from por-built, that he sent me a drive and driven that are nowhere near close. On the freeway cruising with traffic at appx 65mph, mine reads 85+ mph. I've kinda gotten used to it, but I would like to throw the correct ones in there one of these days. Thanks man

Will

 

norcalz28 I like the external accessory you have attached to your car. It really makes your car look good.


but to the real question aren't there some cars that come with the 3.27 gears? might be able to snag one off of there or talk to the dealer.
also are you tires stock height?

 

There might be some 3.27's laying around, but any dealer or gm parts supplier should be able to order them up for you.
https://www.thirdgen.org/newdesign/f...n.shtml#tranny
scroll down a bit to :
Q: I want to buy speedometer drive/driven gears, what are the part numbers and combinations?

and try here for an easy to use calc
http://www.hanlonmotorsports.com/t5speedo.asp