Guys,

Here are spec of stock tires:
215/50/17 93W and diameter 25.5", Circ: 80" and has 819 Rev per mile (loaded) and 791.83 RVM unloaded

Here is my Current tire: Kumho 235/40/18 95W diameter 25.4"Circ: 79.76" and 795 Rev per mile (unloaded).

Now, in 5th gear, at 2000 RPMS my CLS is doing 67-68 MPH.

Simple math with 5th gear at 0.47:1 and final gear ratio of 4.428:1 reveals that (961 Rev/min x 60 min/hr) / 67.5 MPH= 854 Rev per mile loaded!!

from 819 Rev per mile to 854 Rev per mile is a big difference!

So, what is your MPH speed at 2000 rpms in the 5th gear? stock or otherwise...

 

 

X2
No flames - If I am doing 5th gear 2000 rpm, I always concentrate on the road and not staring on the speedometer for that 1 or 2 mph difference.

 

Ah... guys... what is the gig deal... never heard of cruise control... never touch that in your CL-S?

 

the other thing that sux is ur milage is prob going up more then it really is.

 

72 mph @ 2k rpms.

 

I've honestly never used my cruise control.

 

 

You are assuming a lot of things....

Why not just call 1-800-HI-KUMHO and ask for the motor sports department (AKA tech support), and ask for the revs/mile and the loaded radius of 235/45-17 ASX? :thinking: :captobvious:

Using the speedo, eyeballs, and an automatic (locked? partially locked? unlocked? torque converter) to come up with your "figures" is going to be "iffy." Your loaded radius is also affected by inflation pressure and temperature.

The 235/45-17 vs. 215/50-17 Toyo T1S' have revs/mile and loaded radius values that are very close to each other.

A 235/45-17 S03 has a revs/mile of 823.
A 235/45-17 Pilot A/S has a revs/mile of 811