Down side of bigger wheels?
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Diameter debate - covered.
https://www.6speedonline.com/forums/...15s-rears.html
I found this thread very informative when thinking through putting larger tires on the 997TT. It seems that you just need to have a reliable tuner give you solid advice and consult the "learned ones" (those speaking from experience) on this forum. Let's not open the front-rear diameter debate, which is well covered (find your pocket calculator) in the above attached thread.
I found this thread very informative when thinking through putting larger tires on the 997TT. It seems that you just need to have a reliable tuner give you solid advice and consult the "learned ones" (those speaking from experience) on this forum. Let's not open the front-rear diameter debate, which is well covered (find your pocket calculator) in the above attached thread.
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Unsprung rotational mass (ie wheels and tires) have a much greater effect on your acceleration than sprung mass. Ie the effect of adding 1lb unsprung is much more significant (I forget the exact factor, perhaps 4 to 1) than sprung mass. So add 1lb to your wheel setup at each corner, you just added 16lbs of extra weight to your car essentially. And I believe that ratio might be even larger.
Bigger wheels = more weight = slower accel/deccel.
Bigger wheels = more weight = slower accel/deccel.
Larger wheels are slower in acceleration but maintain high speed once attained and take longer to slow or stop. This means larger wheels are a detriment to a drag race but better in an endurance race.
Tire/wheel width can be an issue as well. Too wide interferes with maneuverability. Too narrow is not planted enough. Personally, I'd go with 245 width in front and 295 max in the rear.
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2-MPSC work very good in cold weather and with light-medium rain.
3-MPSC vs PS2 MPSC all the way!
4-MPSC last ok if you dont track them,even with some agressive street driving they last.
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You are correct that bigger wheels will weigh more than smaller wheels of the same exact models. But there are big wheels out there that are incredible in their lightness. Selecting a good, quality, lighter wheel is possible.
Larger wheels are slower in acceleration but maintain high speed once attained and take longer to slow or stop. This means larger wheels are a detriment to a drag race but better in an endurance race.
Tire/wheel width can be an issue as well. Too wide interferes with maneuverability. Too narrow is not planted enough. Personally, I'd go with 245 width in front and 295 max in the rear.
Larger wheels are slower in acceleration but maintain high speed once attained and take longer to slow or stop. This means larger wheels are a detriment to a drag race but better in an endurance race.
Tire/wheel width can be an issue as well. Too wide interferes with maneuverability. Too narrow is not planted enough. Personally, I'd go with 245 width in front and 295 max in the rear.
The best analogy I have heard is the "bowling ball". Hold it close to your chest and turn circles and it is not too difficult. Hold the ball at arms length and the circles get a lot tougher to turn. The weight in both cases is the same, but the "moment of inertia" is very different.
The engineering goal is to keep the weight as close to the center of the wheel as possible, while making the wheel strong enough to support the vehicle and resist road hazards.
This is one reason why forged wheels are so popular for high performance. They have low mass, low unsprung weight and low "moment of inertia" (if they are properly engineered).
By the way, the low moment of inertia also works for deceleration, so it enhances braking as well as acceleration.
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I thought the MPSC wouldn't hold up so well, but they are suprisingly good. I've got I believe about 5500-6000 miles on them with about 5 track days thus far, and still have tread remaining. Not to mention they are loads quieter than the Toyo R888s and seem to perform better and definitely communicate more.
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My last outing I bled off to 31 before starting at Watkins Glen and in half a session was up to 37+, outside temperature was around 45.
I'm running a little less camber now then when I was on the Toyos (-2.5 vs -2.0) but the MSPC seem to be holding up well.
I also drive them to and from the track and I find them to perform a lot better in the rain. The Toyos were constantly hydroplaning and so far the MSPC havent even though I've been in some decent rainfalls.
And you cant compare the night and day difference in terms of road noise.
Personally I'm sold on the MSPC wouldnt go back to the Toyos.
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You are correct that bigger wheels will weigh more than smaller wheels of the same exact models. But there are big wheels out there that are incredible in their lightness. Selecting a good, quality, lighter wheel is possible.
Larger wheels are slower in acceleration but maintain high speed once attained and take longer to slow or stop. This means larger wheels are a detriment to a drag race but better in an endurance race.
Tire/wheel width can be an issue as well. Too wide interferes with maneuverability. Too narrow is not planted enough. Personally, I'd go with 245 width in front and 295 max in the rear.
Larger wheels are slower in acceleration but maintain high speed once attained and take longer to slow or stop. This means larger wheels are a detriment to a drag race but better in an endurance race.
Tire/wheel width can be an issue as well. Too wide interferes with maneuverability. Too narrow is not planted enough. Personally, I'd go with 245 width in front and 295 max in the rear.
I suppose you could do all the applicable math between wheel/tire combos to figure out the optimal setup for you that gives you the performance you want as well as the looks...
The best analogy I have heard is the "bowling ball". Hold it close to your chest and turn circles and it is not too difficult. Hold the ball at arms length and the circles get a lot tougher to turn. The weight in both cases is the same, but the "moment of inertia" is very different.
The engineering goal is to keep the weight as close to the center of the wheel as possible, while making the wheel strong enough to support the vehicle and resist road hazards.
This is one reason why forged wheels are so popular for high performance. They have low mass, low unsprung weight and low "moment of inertia" (if they are properly engineered).
By the way, the low moment of inertia also works for deceleration, so it enhances braking as well as acceleration.
The engineering goal is to keep the weight as close to the center of the wheel as possible, while making the wheel strong enough to support the vehicle and resist road hazards.
This is one reason why forged wheels are so popular for high performance. They have low mass, low unsprung weight and low "moment of inertia" (if they are properly engineered).
By the way, the low moment of inertia also works for deceleration, so it enhances braking as well as acceleration.
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I thought the MPSC wouldn't hold up so well, but they are suprisingly good. I've got I believe about 5500-6000 miles on them with about 5 track days thus far, and still have tread remaining. Not to mention they are loads quieter than the Toyo R888s and seem to perform better and definitely communicate more.
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