05RollaXRS

Yes, I believe the ISF guys have swapped the final drive with the 2IS350 6 speed auto final drive, which was a shorter drive (numerically higher). I believe, it was 4:09:1. That gives more torque multiplication to the wheels.

Edit: Found a video. You can see how it really tightens the ratio stack.

rfugio68

Do they make gears for our cars? If they do it should be an easy swap, would RR be able to tune to them? That way we don't get speed limited by gear like the isf guys who switched to the is350 diff

lobuxracer

iTrader: (2)

With an 8 speed gearbox, changing the diff only makes a difference in first gear. After that, there is nothing to be gained. It's very easy to stay in the thick of the powerband once you get there. I had a very long and mathematically challenging discussion with a friend about this as I was entertaining a ratio change when I put in my OS Giken spool. It would obviously be the perfect time to swap ratios. After much discussion, back and forth, the numbers don't support a final drive ratio change unless you want first gear to spin up faster than it does. Beyond that, you gain nothing. Seeing the truth - these cars all have traction issues off the line - the only real gain is tiny and requires significantly more focus to extract. None of the guys in the F forum kept the low gears. BTW, all of this assumes you are not being lazy and are in the right gear to extract full power from the engine when you mash the gas.