PRAY HRD

iTrader: (119)

Guys i'm not sure if this is the right section for this but just wondering if there's a formula to figure this out. I'm looking at running a 26" tire n/a and was trying to figure out what a 3.70/26" combo is equal to gear wise with a 28" tall tire.

Thanks a bunch!

BlackScreaminMachine

iTrader: (17)

http://www.csgnetwork.com/multirpmcalc.html

This does work, but your est your MPH if you do not know it already. I know there is a better one out there but I gotta search when its less busy at work.

5.3LJimmy

iTrader: (10)

You divide the roll out(circumference) of 28" tire by the roll out of the 26" tire and multiply the gear ratio by the result.

Ex: 28x3.1416=87.96
26x3.1416=81.68
87.96/81.68=1.077
3.70x1.077=3.98

It will take a 3.98:1 gear to keep it exactly the same. Because they may not make a 3.98 gear you choose the closest available.

5.3LJimmy

iTrader: (10)

I just re-read your question and realized you may be asking what your effective gear ratio would be if keeping the same gear and going to a 28" tire. If this is the case then you would divide the current gear by the tire ratio. So: 3.70/1.077=3.43

PRAY HRD

iTrader: (119)

No this is what i was looking for and it's greatly appreciated!! I'm going from 4.11's with a 28" as the previous owner had the car to a 3.73 to run spray and was wondering what the equivalent would be with a 26" tire so that's not too far off! That means i need to get a set of rims to run just for n/a with 26's on them to be very close to where it was before.

Thanks a Ton!!