I'm trying to work out what speedo gears I'm needing for 3.42 gears with a stock IROC wheel with 245/50/16s on them. I can't find the tire height anywhere.

Does anyone know the height, or indeed what gears are needed?

Cheers.

 

if its the stock tire its 26"

 

just did a 342 swap. you need a 15tooth drive and a 40 tooth driven.

15tooth is a gray gear 40tooth is a black gear. part numbers are in the stickys (drivetrain section) the 40 tooth driven needs the larger speedo housing. should be about 99.8% accurate, meaning it will read a hair (.2%) fast but if you step up to a 41 driven you will read much slower (-.3%)

 

http://www.rimsntires.com/rt_specs.j...&text1=&text2=

 

Thank you gents, I got the grey and the black. Was on holiday and had limited access to computer and internet resources!