I've been searching for info on this that I know I've seen posted before, but can't find it for the life of me. There was this that took stock tire size and stock final drive ratio and by inputting differing tire sizes, you would be given a of your new final drive ratio. I ask because I'm going to be running 255/40/17's and can't decide between a 4.77 and 5.12 ring and pinion.


Any help is greatly appreciated.

 

Here's one that I've used before. I've used a different one that sounds more of what you're looking for. I'll see if I can find it.

Tire Size Calculator - Tire & Wheel Plus Sizing

Edit. Here's another one: http://tire-size-conversion.com/tire-size-calculator/

I found where you can input the gear ratio: http://tire-size-conversion.com/gear-ratio-calculator/

 

Awesome, you sir are a life saver! Thank you very much.

 

I forgot to mention, if anyone is interested- running a 4.77 ring and pinion with a 255/40/17 tire yields a final drive ratio of 4.96:1. That's an outstanding ratio for low power NA cars.

 

Search google for MFactory Gear Calculator. That one is by far the best and spits out interactive graphs and shift information as well.

 

[original tire OD/new tire OD] x rear gear ratio = new effective gear ratio

where can I get a calculator to tie my shoe laces for me too?

Toyo R1R 245/35/17 = 23.8" OD ....

 

Arca- Will do, thanks.

Team- Helpful as usual. [/sarcasm]