I have a 92 camaro 10 bolt with 3.73 gears. speedo is a 145mph, and tire is 255/50-16. the trans came out of car with a 115 speedo. I read about 50mph off. I know i need new drive and driven gears but there are so many combos. does anyone either know what I need. or know how many revs per mph the 145 speedo is. I found a formula online but need that revolutions number to use it. Thanks in advance

 

go to transmissioncenter.net. They have a chart that will tell you what you need & they also sell the needed hardware.

 

Thanks for link, however I need the rev/mile of my 145mph speedo to make the calculation

 

For a 700R4 with 3.73 rear gears, you will need a 15 tooth drive gear and a 45 tooth driven gear (possibly with a new sending unit in the trans). You can find more info in the Tranny/Drivetrain forum.