litch2004

iTrader: (1)

I am looking for what would be a well suited gear ratio for a 28" tire and an A4 trans. This will have some street time but im trying to get a ratio with the equivalent of having a 26" tire. Any help is greatly appreciated in advance.

LS1_Sean

iTrader: (1)

Not sure on what gear will give you the equivlant of a 26" tire. But im guessing you have a M6? most people got with 4.10's 3.73 for A4.

litch2004

iTrader: (1)

no i have A4. i do understand that going with a 3.73 in my case would be ideal. I bought rims at first only wanting for the look but after thinking more into it i figured i would get the full use out of the drag wheels. I already have MT 325/50/15s which is a 28" tire. So with that said i am trying to figure out which gear ratio (w/A4) would get me closer to the same tire/gear ratio as a 26" tire w/3.73's. The reason of doing this by the way is that a 28" tire is to tall for my mods/setup and just don't want to get rid of them now. Down the road once my motor is built i will be needing this size wheel.

litch2004

iTrader: (1)

T t t

alamantia

iTrader: (10)

Did you take algebra in highschool?

FirstYrLS1Z

iTrader: (4)

4.10s'
http://www.f-body.org/gears/

alamantia

iTrader: (10)

I will break down the calculator...

To find the circumference of a circle (or tire) you multiply the diameter times pie (3.14)

26" tall tire has a circumference of 26 x 3.14 = 81.64"
28" tall tire has a circumference of 28 x 3.13 = 87.92"

There are 5280 feet in a mile, so thats 63,360"

If you divide 63,360" by the 26" tall tire. (63,360 / 81.64) you see that the 26" tall tire must rotate 776.1 times to cover a mile

If you divide 63,360" by the 28" tall tire. (63,360 / 87.92) you see that the 26" tall tire must rotate 720.6 times to cover a mile

Multiply 776 x 3.42 to find out how many times your driveshaft rotates in a mile with a 26" tall tire and you will find that the driveshaft rotates 2653.92 times

Now multiply 720.6 x 3.42
Now multiply 720.6 x 3.73
Now multiply 720.6 x 3.90
Now multiply 720.6 x 4.10
Now multiply 720.6 x 4.30
Now multiply 720.6 x 4.56


Which gets you the closest to 2653.93?

litch2004

iTrader: (1)

well looks like 3.90 gears are going to be the closest to running a 26"tire with 3.73's. Not sure if you were being a smart *** in your first post alamantia but thank you for the break down. i wouldn't have thought to have done it this way.