Final Drive Ratio, wheel, and WHP changes

Originally Posted by Rusty

N/A, the 4.08 works good for the strip. Going boost. Most guys want to go to the 3.54, or the 3.30 gears. As 1st gear, and the bottom of 2nd gear is overpowered by engine torque.

Using the OS Giken diff. You have to use the OS Giken lube to keep it quite. Otherwise, it gets noisy. After install, change the lube after 1000 miles. The lube used to be $70.00 a liter. Now I see it's $50.00 a liter. I have one, and it works great. Get the Z1 finned diff cover too. I recorded temps of 265F in my diff. The cover will hold an extra 1/2 liter of lube.

Originally Posted by JeffP-Z

Thanks for the info and advice. Yes I already have the z1 diff cover on the build list. It is getting done July 9th. Unfortunately I am down until then as the planetary gears in the stock diff let go Thursday night. It is totally dead for now.

Originally Posted by Spooler

If you go boosted, you will want 3.33 gears. If you don't know which way to go stay stock gearing for now.