?? technical question about gearing
Thread Starter
Intermediate
Joined: Apr 2004
Posts: 35
Likes: 0
From: Columbia SC
?? technical question about gearing
I need someone who is technically inclined to lend a hand.
My C5 is a 6 spd with 343 gears and 345 tires (27.4" tall),
the car came with tires that were 26.8" tall
I now have to go to a 335/30/18 tire as the 345 is dicontinued
at any rate, the 335"s are 26.1" tall
so my question is... what gear ratio am I currently running considering I have tires that are taller than the stock ones?
AND... what gear ratio will this equate to when I run a shorter tire?
ALSO... let's say that I now run 1500 RPM at 70 (6th gear) and I want to run about 300 more RPM. What gear do I need to put in the car?
Thanks for your help! I really need it!
My C5 is a 6 spd with 343 gears and 345 tires (27.4" tall),
the car came with tires that were 26.8" tall
I now have to go to a 335/30/18 tire as the 345 is dicontinued
at any rate, the 335"s are 26.1" tall
so my question is... what gear ratio am I currently running considering I have tires that are taller than the stock ones?
AND... what gear ratio will this equate to when I run a shorter tire?
ALSO... let's say that I now run 1500 RPM at 70 (6th gear) and I want to run about 300 more RPM. What gear do I need to put in the car?
Thanks for your help! I really need it!
Safety Car
Joined: May 2000
Posts: 4,808
Likes: 344
From: Albuquerque NM
Even though those size changes sound big, they really were only about 3% each. Your 3.42's acted like 3.33's with the tall tires, and will pull revs like 3.50's with the short tires. If you want 1800 rpm with the new short tires you will need to run 3.90:1 rear gears. Hope this is what you are looking for. 
