ok, I got my 3.90s in and i also have low profile tires. The speedometer says i'm going 90 when i'm going 70. Found this out by following someone while on a cell phone [&:]. So, I take it that I have a 7 to 9 ratio or however u would put that. I want to get it changed back to the right speed. I dont care how fast i'm going, but it is making the mileage on my car higher than it really is. So, my question to you is: Is there any way that I can correct the speedometer and not have to pay the rediculous prices of a diablo or all those other brands?

 

Get a speedcal. They cost $100.

 

What year car are you?

 

02

 

That would work, here's the link: http://www.americanmuscle.com/speed-...tor-94-04.html

If you are a pre 99, you can use a spedo gear that goes in your transmission.

Ok, since you're an 02, your cheapest option is the Speedcal as far as I know.