Tire Sizes and Active Handling ...
Thread Starter
Melting Slicks
Joined: Oct 2005
Posts: 2,877
Likes: 9
From: Ottawa Ontario
Tire Sizes and Active Handling ...
Hey guys
I have read that the overall diameter of the rear tire needs to be larger than the front or the active handling will do odd things. The questions I have is can they be equal in size? Also if the rear diameter has to be larger does it need to be larger by a certain amount?
I was interested in going with the following combo 315/30/18 and 275/40/17 which looks like it won't work as the diamters are the same or the front is slightly larger. I guess i could go to a 255/40/17 up front because the do not have a 305/35/18 avaliable for the rears.
Also will the 315's rub on the wheels well or brake cooling vent?
I was going to maybe give these units a shot
http://www.falkentire.com/rt615_sizes.html
Guess I may have to go with the Nitto 555R2's...was just trying to get a little better treadwear as well as some rain control.
Thanks for any input
!
I have read that the overall diameter of the rear tire needs to be larger than the front or the active handling will do odd things. The questions I have is can they be equal in size? Also if the rear diameter has to be larger does it need to be larger by a certain amount?
I was interested in going with the following combo 315/30/18 and 275/40/17 which looks like it won't work as the diamters are the same or the front is slightly larger. I guess i could go to a 255/40/17 up front because the do not have a 305/35/18 avaliable for the rears.
Also will the 315's rub on the wheels well or brake cooling vent?
I was going to maybe give these units a shot
http://www.falkentire.com/rt615_sizes.html
Guess I may have to go with the Nitto 555R2's...was just trying to get a little better treadwear as well as some rain control.
Thanks for any input
!
Last edited by MotleyDrew; Feb 11, 2007 at 11:07 PM.
Safety Car
Joined: Oct 2004
Posts: 4,816
Likes: 132
From: Plano TX
Yes, the rears need to be larger by 1/2 inch or so, otherwise your traction control will kick in.. The computer senses that the rear wheels are spinning. You won't get to far in this situation.. Do a search for more information.. There may be away to manipulate the PCM to accomodate your wheels and tires. I'm no expert on this
Thread Starter
Melting Slicks
Joined: Oct 2005
Posts: 2,877
Likes: 9
From: Ottawa Ontario
Yes, the rears need to be larger by 1/2 inch or so, otherwise your traction control will kick in.. The computer senses that the rear wheels are spinning. You won't get to far in this situation.. Do a search for more information.. There may be away to manipulate the PCM to accomodate your wheels and tires. I'm no expert on this
Melting Slicks
Joined: Feb 2001
Posts: 2,804
Likes: 358
From: Northville, MI
I run my hoosiers at even diameters front and rear and do not have any TC problems, most of the time at the track but on an occaisional local scan/log run on the street/interstate. At the track, the AH is off but on a scanning run it is on.
Former Vendor
Joined: May 2006
Posts: 718
Likes: 1
From: Riviera Beach FL
I am running 275/35/18 front and 315/30/18 on the rear. According to Tire Rack the front diameter measure 25.6 @ 814 revolutions per mile. The rears are 25.9 @ 817 revolutions per mile. I have never had a problem with active handling. Just some more information to add to the fire.
Doug
Doug
Burning Brakes
Joined: Jan 2006
Posts: 1,170
Likes: 27
From: Magnolia Greens NC
Options..
If you disable (turn off) the AH/TC feature you can use just about any front/rear tire combo that fits...but if you want AH/TC to perform as designed by Bowling Green...you should maintain the original front to rear tire diameter ratio.
Thread Starter
Melting Slicks
Joined: Oct 2005
Posts: 2,877
Likes: 9
From: Ottawa Ontario
thanks guys
I just decided to go with 255\40\17 up front and the 315\30\18's in the rear. The difference in total diameter is 25.0 front and 25.6 in the rear.
I thought I would give the new Falken AZENIS RT-615's a try. Nothing is gonna hook up on the street for me short of full slicks so.....
I like having the safey net of the active handling as I run in Competion Mode all the time.
thanks again for the responses !
I just decided to go with 255\40\17 up front and the 315\30\18's in the rear. The difference in total diameter is 25.0 front and 25.6 in the rear.
I thought I would give the new Falken AZENIS RT-615's a try. Nothing is gonna hook up on the street for me short of full slicks so.....
I like having the safey net of the active handling as I run in Competion Mode all the time.
thanks again for the responses !
Drifting
Joined: Mar 2006
Posts: 1,872
Likes: 7
From: Richmond VA
I am running 275/35/18 front and 315/30/18 on the rear. According to Tire Rack the front diameter measure 25.6 @ 814 revolutions per mile. The rears are 25.9 @ 817 revolutions per mile. I have never had a problem with active handling. Just some more information to add to the fire.
Doug
Doug
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Le Mans Master
Joined: Dec 2003
Posts: 5,561
Likes: 448
From: Atlanta metro Ga.
Le Mans Master
Joined: Dec 2000
Posts: 9,909
Likes: 1,858
From: Hot Springs AR
Have a good one,
Mike
Race Director
Joined: May 2005
Posts: 15,960
Likes: 21
From: West Norriton PA
St. Jude Donor '08
The XX in your post is the profile height.
What you need to look at is the tire chart for the tire brand you are interested in and make sure that the over-all tire heigt is 1/2" taller in the rear than the front if you have AH, if you don't have AH you're free to do what you want.
Pro
Joined: Oct 2003
Posts: 560
Likes: 0
From: nanticoke pa
wheel/tire size
heres an easy was to figure out the size of tires/wheels:
take the tire width mutiply by the profile then divide by 1270 then add the rim size to it and you have the overall tire/wheel height.
exp: 255/35 18 fronts 285/35 18 rears
255 x 35 divided by 1270 + 18 = 25.02
285 x 35 divided by 1270 + 18 = 25.85
this is what im running on my car fronts 255, rears 285. you must have at least 1/2 inch higher on the rear. hope this helps. brad
take the tire width mutiply by the profile then divide by 1270 then add the rim size to it and you have the overall tire/wheel height.
exp: 255/35 18 fronts 285/35 18 rears
255 x 35 divided by 1270 + 18 = 25.02
285 x 35 divided by 1270 + 18 = 25.85
this is what im running on my car fronts 255, rears 285. you must have at least 1/2 inch higher on the rear. hope this helps. brad
Racer
Joined: Feb 2007
Posts: 431
Likes: 5
From: Chico CA
