Kuhmo Ecsta's in 235/40 F and 275/40 R any ABS problems?
03-23-2003, 10:58 AM
#1
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Kuhmo Ecsta's in 235/40 F and 275/40 R any ABS problems?
Anyone used the Kuhmo Ecsta's in 235/40 front and 275/40 rear on their 964? I want to try the combination but I am concerned about ABS problems due to their diameter differences.
The owners manual warns that the radii of tires used must be within 6% of the "standard tire". Both the tires above are withing 6% of the stock tires but there will be a 4.2% difference between the front and rear and I'm concerned this may create ABS issues.
Anyone done these tire sizes sucessfully and what pressures did you use for Auto-X?
The owners manual warns that the radii of tires used must be within 6% of the "standard tire". Both the tires above are withing 6% of the stock tires but there will be a 4.2% difference between the front and rear and I'm concerned this may create ABS issues.
Anyone done these tire sizes sucessfully and what pressures did you use for Auto-X?
03-23-2003, 11:52 PM
#2
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I just noticed on the Tirerack website this note on the Ecsta V700's (which wasn't there when I bought mine last year):
The ECSTA V700 must be shaved to 3/32" - 4/32" tread depth for any autocross or track use in the dry.
Kumho advises that the ECSTA V700 DOT-legal competition radial must be shaved prior to use in dry conditions. If this tire is not shaved, excessive wear may occur causing the tire to wear to the cords prematurely in a localized area.
Tire heat cycling will not prevent the excessive localized wear of full tread depth tires but will continue to enhance the tire consistency and wear on shaved tires.
The ECSTA V700 should only be used at full tread depth (6/32") for wet track and wet autocross use.
The ECSTA V700 must be shaved to 3/32" - 4/32" tread depth for any autocross or track use in the dry.
Kumho advises that the ECSTA V700 DOT-legal competition radial must be shaved prior to use in dry conditions. If this tire is not shaved, excessive wear may occur causing the tire to wear to the cords prematurely in a localized area.
Tire heat cycling will not prevent the excessive localized wear of full tread depth tires but will continue to enhance the tire consistency and wear on shaved tires.
The ECSTA V700 should only be used at full tread depth (6/32") for wet track and wet autocross use.
03-24-2003, 11:16 AM
#3
I'm running these tires on my 965 on 8x17 front and 10x17 rear rims.
No adverse effect on ABS (that I can tell).
Over all I'm not happy with this tire setup. My previous tires were 225 front and 275 rear Kumho Victoracers. They do not have the same "grip" or feel as the Victoracers. At last years National Tour I had an opportunity to talk to one of the Kumho Tech reps and he advised I lower my tire pressures and dial in more negative camber up front. I can only get 1.2 degrees negative with the stock setup up front (2 in the rear). There's been a lot of talk about the Ecstas, unforturnately mostly negative. So much so that Kumho had to put out a note on their web site defending the tires. Kinda makes you think...
I've tried the range of tire pressures and feel the best is 30 to 32 up front and 34-36 in the rear. On the track they feel good but get greasy after about 20 minutes. On the autocross, they don't "feel" good until the 4th run.
I didn't have the tires shaved and the wear so far is not the best (uneven). I'll see if I can get a pic this afternoon. Hey Bill, did you get yours shaved? How's the wear so far??
No adverse effect on ABS (that I can tell).
Over all I'm not happy with this tire setup. My previous tires were 225 front and 275 rear Kumho Victoracers. They do not have the same "grip" or feel as the Victoracers. At last years National Tour I had an opportunity to talk to one of the Kumho Tech reps and he advised I lower my tire pressures and dial in more negative camber up front. I can only get 1.2 degrees negative with the stock setup up front (2 in the rear). There's been a lot of talk about the Ecstas, unforturnately mostly negative. So much so that Kumho had to put out a note on their web site defending the tires. Kinda makes you think...
I've tried the range of tire pressures and feel the best is 30 to 32 up front and 34-36 in the rear. On the track they feel good but get greasy after about 20 minutes. On the autocross, they don't "feel" good until the 4th run.
I didn't have the tires shaved and the wear so far is not the best (uneven). I'll see if I can get a pic this afternoon. Hey Bill, did you get yours shaved? How's the wear so far??
03-24-2003, 01:40 PM
#4
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Jeff,
I've used mine from stock with no shaving, and the wear has been good overall, except for swapping them side to side for camber wear considerations (I have greater than -2 front and rear).
I too find they get greasy after around 10 minutes - leads to some unwelcome behaviour when on the hairy edge. So far, knock on my head, they've worn well for me, however, I won't get them again. Since I just ordered Michelin Cups last night, as they Ecsta's will be done in 4-5 days, that means Hoosier will come out with their supposedly-in-the-works Michelin Cup competitor and hopefully factor in some price competition.
I've used mine from stock with no shaving, and the wear has been good overall, except for swapping them side to side for camber wear considerations (I have greater than -2 front and rear).
I too find they get greasy after around 10 minutes - leads to some unwelcome behaviour when on the hairy edge. So far, knock on my head, they've worn well for me, however, I won't get them again. Since I just ordered Michelin Cups last night, as they Ecsta's will be done in 4-5 days, that means Hoosier will come out with their supposedly-in-the-works Michelin Cup competitor and hopefully factor in some price competition.
03-24-2003, 04:00 PM
#5
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Thread Starter
Jeff and Bill- Thanks for your replies, I went ahead and bought a set of Ecstas in the 235 and 275 sizes and will be running them with 2.4 degrees of negative camber front and rear.
The ABS light didn't come on so I guess it's computer is happy. I might not have bought the tires given your input but I already had them on order and had to satisfy my curiosity. Thanks again.
The ABS light didn't come on so I guess it's computer is happy. I might not have bought the tires given your input but I already had them on order and had to satisfy my curiosity. Thanks again.
