Contemplating Rear Gear change - ZR-1 Net Registry Forums

WVZR-1 · 09-18-2011

You didn't actually mention MPH in your initial post, only a % and that you were confident that the gear was a 3.45. The 3.45 gear, 12-15% error didn't work with any of the 19" tires that I was aware people were using. That suggested an error someplace. Now we're assuming the error is the drive/driven combination?

The 3.73 certainly would likely accomplish the performance balance you're looking to accomplish and while I was doing it I'd certainly check the drive gear in the transmission. If it's been changed to the 13 tooth to accomplish speedometer correction for 4.10's then I'd go back to the stock 15 tooth which makes correction with the 3.73 quite easy.

You would require a lesser tooth count than the 45 tooth if you wished to change and that's pretty straight forward. If it's a 13 tooth and you required a tooth count of less than 40 that usually suggests a different VSS that's indexed differently. You could also accomplish it with the DRA suggested.

I've always assumed a mechanical correction is the preferred.

09-18-2011	#11
WVZR-1 Join Date: Oct 2004 Posts: 1,890	Re: Contemplating Rear Gear change You didn't actually mention MPH in your initial post, only a % and that you were confident that the gear was a 3.45. The 3.45 gear, 12-15% error didn't work with any of the 19" tires that I was aware people were using. That suggested an error someplace. Now we're assuming the error is the drive/driven combination? The 3.73 certainly would likely accomplish the performance balance you're looking to accomplish and while I was doing it I'd certainly check the drive gear in the transmission. If it's been changed to the 13 tooth to accomplish speedometer correction for 4.10's then I'd go back to the stock 15 tooth which makes correction with the 3.73 quite easy. You would require a lesser tooth count than the 45 tooth if you wished to change and that's pretty straight forward. If it's a 13 tooth and you required a tooth count of less than 40 that usually suggests a different VSS that's indexed differently. You could also accomplish it with the DRA suggested. I've always assumed a mechanical correction is the preferred. Last edited by WVZR-1; 09-18-2011 at 12:44 PM.