Help me with an argument, please?
03-17-2006, 10:58 AM
#17
Administrator - "Tyson"
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Originally Posted by Geo
Where is it? I'll be there. 
Here is the back story. This is my best friend I'm having this discussion with. His family owns Corvette Sports in Sheboygan Falls Wisconsin. Needless to say, they know quite a bit about Corvette's. They have setup quite a few impressive race cars including some in the Speed GT series, the #1 Penske Grand Sport and various other race teams that make their way to Wisconsin.
Anyway - he is helping me find some "take off" race tires from the pro teams he deals with. I sent him my new wheels size (8x18 - 10x18 997 wheels) for my 79 928. He asked why I wouldn't opt for the largest size that would fit that wheel correctly. I'm worried about loosing top end speed on the straights due to a low hp car with too much rubber (Road America is my main track). So that is where the discussion started.
My 79 has a stock drive train with headers. Upgraded suspension lowered about 3" with S4 4-piston Brembo brakes all around.
He is used to dealing with ZO6 Corvettes with 375-500 rwhp where they cannot fit enough rubber in the fender.
I plan to run the Continental tires coming with my wheels for the first DE this season.
03-17-2006, 11:04 AM
#18
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I don't know if you really lost the argument. If your side was that there is a width that would be too wide for a given application, I have to believe the answer is yes. This is ridiculous but imagine a 50 foot wide tire on your car.
Last edited by mitch236; 03-17-2006 at 11:20 AM. Reason: spelling
03-17-2006, 11:13 AM
#19
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Originally Posted by Premier Motorsp
Bigger is better, as long as you can get tires designed properly for your application.
If you are forced to use tires that are the wrong compound or construction or too big for the wheel, then they won't help.
They don't have maximum tire size rules in pro racing for nothing. Without those rules, the tires would as wide as the tire company could physically make them.
Cornering speed is WAY more important than drag or acceleration. This is obvious if you compare the lap times of cars that accelerate hard and corner poorly (i.e. fast street cars) vs. cars that accelerate slowly but corner well.
Chris Cervelli
Premier Motorsports
If you are forced to use tires that are the wrong compound or construction or too big for the wheel, then they won't help.
They don't have maximum tire size rules in pro racing for nothing. Without those rules, the tires would as wide as the tire company could physically make them.
Cornering speed is WAY more important than drag or acceleration. This is obvious if you compare the lap times of cars that accelerate hard and corner poorly (i.e. fast street cars) vs. cars that accelerate slowly but corner well.
Chris Cervelli
Premier Motorsports
What do you think about the trade off between width and height. I remember a few years ago when you were club racing a 996 in C you advocated switching from 285s to 305s. I switched to 305s for awhile but found the extra inch of height hurt acceleration. The gear charts say that a 4500 to 7000 rpm run in 4th with 285s nets 43.75 mph vs 45.54 with 305 which is pretty significant. I assume the 3 extra pounds don't help either. On the other hand, the 285s stick for awhile but get pretty squirrelly 20 minutes in. Any words of wisdom?
I've race a 3.6L X51 in C. Thanks.
Jim
03-17-2006, 11:17 AM
#20
Burning Brakes
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Imagine a Formula V or go kart with 245's ? Are you REALLY going to get any more grip ?
I guess physical grip (the stickyness) will increase, but you have to heat them up first.
I guess physical grip (the stickyness) will increase, but you have to heat them up first.
03-17-2006, 11:52 AM
#21
It's also a function of the tires that are available. For example, I truly believe people have cold weather issues with MPSC's because they are using too wide of a tire. They're not getting them hot enough. It's especially true on the lower horsepower cars that don't work the rears hard. In a Hoosier you may get the fastest lap times out of a 265/275 whereas the MPSC may work better in a 245/255. That's not saying that the MPSC is faster than the Hoosier but that the MPSC may be faster in a smaller rather than larger footprint.
03-17-2006, 12:53 PM
#23
Race Director
Originally Posted by Hacker-Pschorr
This is Wisconsin - we ALWAYS include beer! Get your *** to Road America one of these PCA weekends.
Got to make sure someone brings the brats too!
03-17-2006, 01:29 PM
#25
I think the more important issue is can your suspension get the use from the wider tire... as the tire gets wider it is much more sensitive to camber changes. If your car is relatively soft sprung, and suspension creates alot of camber change a wider tire isn;t going to work effectively.
03-17-2006, 02:11 PM
#26
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Originally Posted by Bull
I think it is a tie and that you both should buy beer for all those who added to this thread (duck!).
Needless to say, we are never very far away form a large amount of suds. Any Rennlisters who make it to Road America (and find me or I find them) can be guarnteed a beer at Siebkens.
As far at the brats go - Johnsonville is about 5 minutes away from my friends Corvette shop, brats will not be a problem!
Ok, time to plug their shop I guess:
www.corvettesports.com
The silver GS in front is my friends car. Everytime he blows by me on the straights I remember the day I passed that car up...
03-17-2006, 05:18 PM
#27
Mr. Excitement
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Originally Posted by Premier Motorsp
Bigger is better, as long as you can get tires designed properly for your application.
If you are forced to use tires that are the wrong compound or construction or too big for the wheel, then they won't help.
They don't have maximum tire size rules in pro racing for nothing. Without those rules, the tires would as wide as the tire company could physically make them.
Cornering speed is WAY more important than drag or acceleration. This is obvious if you compare the lap times of cars that accelerate hard and corner poorly (i.e. fast street cars) vs. cars that accelerate slowly but corner well.
Chris Cervelli
Premier Motorsports
If you are forced to use tires that are the wrong compound or construction or too big for the wheel, then they won't help.
They don't have maximum tire size rules in pro racing for nothing. Without those rules, the tires would as wide as the tire company could physically make them.
Cornering speed is WAY more important than drag or acceleration. This is obvious if you compare the lap times of cars that accelerate hard and corner poorly (i.e. fast street cars) vs. cars that accelerate slowly but corner well.
Chris Cervelli
Premier Motorsports
03-17-2006, 06:22 PM
#28
Race Car
The short answer is: wider is better. While there is certainly a point of diminishing returns with tire width, it doesn't come within the commercially-available sizes for the vast majority of our cars.
