Need Help Re; Diff Ratio's

[wsln33]

Hey guys, need some help.

I've got an R33 gtst which I converted to 3sp auto, still has the manual diff in it.

When I raced it the other week at heathcote, it was maxing out before the finish line.

How do i work out what I need to change my diff ratio's to, in order to gain a higher top speed

[BezerkR32]

you use the moroso calculator, how far before the finish line? you can go a taller tyre if its only 50 meters.

Hey guys, need some help.

I've got an R33 gtst which I converted to 3sp auto, still has the manual diff in it.

When I raced it the other week at heathcote, it was maxing out before the finish line.

How do i work out what I need to change my diff ratio's to, in order to gain a higher top speed

[bubba]

If it helps I'm running 3.9:1 gears out of an auto S13 (stock 33gtst is 4.1:1 I think) and it dropped my revs in 5th @ 100kmh by a bit over 500rpm (3000 down to 2500) but that's going from my stock 4.3:1 gears.

Edited April 23, 2010 by bubba

[BQQ57]

3.9's