I have an 03 gt and I am installing 3.73 gears in it thursday and I was wondering if anyone knows the speed difference vs stock gears. example with stock gears running 65 mph what will I really be running with 3.73's when my speedo says 65 mph? I know I can buy many things to correct this with but I am short on cash right now so that will have to wait. I don't want to get a speeding ticket while I am waiting.

 

http://tchracing.com/tech/gearcalc.p...selectedgear=2

 

You are going to want to fix it asap or else your mileage is going to rack up like crazy...

 

I just now thought about that after reading your post. I've had 3.73's for a couple months now but haven't purchased a tuner to input the new gear ratio. I wonder how many miles highermy odometer isreading? I think the speedo reads around 14% higher than whatI'm actually doing. Oh well, especially now I really want to get a tuner. I hear SCT is one of the better ones. Does anyone know where a good place on line to buy one is and how much I would expect to spend?

 

you can also think about getting a speedcal or white speedo gear.