18s vs. 19s, bad idea?
#31
Racer
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How can mechanical grip be increased simply by going to a larger diameter? My opinion is you increase mechanical grip by either going with a wider tire, or going to a softer tire.
My experience tells me that of an 18" and 19" diameter tire of the same widths and compounds, the 18" is going to have more inherent grip due to it's ability to absorb more bumps through it's taller sidewall, thus keeping more tread on the ground. In addition, tires need to "roll over" slightly on their sidewalls for optimum grip, and an 18" tire is going to do this easier than a 19".
Look at a Champ Car or F1, or even an ALMS-type tire. They are the ultimate race tires, yet they are not extremely low-profile.
19" is for looks alone, IMO.
My experience tells me that of an 18" and 19" diameter tire of the same widths and compounds, the 18" is going to have more inherent grip due to it's ability to absorb more bumps through it's taller sidewall, thus keeping more tread on the ground. In addition, tires need to "roll over" slightly on their sidewalls for optimum grip, and an 18" tire is going to do this easier than a 19".
Look at a Champ Car or F1, or even an ALMS-type tire. They are the ultimate race tires, yet they are not extremely low-profile.
19" is for looks alone, IMO.
#32
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Originally Posted by SRL
How can mechanical grip be increased simply by going to a larger diameter? My opinion is you increase mechanical grip by either going with a wider tire, or going to a softer tire.
My experience tells me that of an 18" and 19" diameter tire of the same widths and compounds, the 18" is going to have more inherent grip due to it's ability to absorb more bumps through it's taller sidewall, thus keeping more tread on the ground. In addition, tires need to "roll over" slightly on their sidewalls for optimum grip, and an 18" tire is going to do this easier than a 19".
Look at a Champ Car or F1, or even an ALMS-type tire. They are the ultimate race tires, yet they are not extremely low-profile.
19" is for looks alone, IMO.
My experience tells me that of an 18" and 19" diameter tire of the same widths and compounds, the 18" is going to have more inherent grip due to it's ability to absorb more bumps through it's taller sidewall, thus keeping more tread on the ground. In addition, tires need to "roll over" slightly on their sidewalls for optimum grip, and an 18" tire is going to do this easier than a 19".
Look at a Champ Car or F1, or even an ALMS-type tire. They are the ultimate race tires, yet they are not extremely low-profile.
19" is for looks alone, IMO.
9ff said it, not me
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#33
Pro
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Originally Posted by karlooz
regarding performance benefits...
9ff and manthey racing chose do go with 18s instead of 19s stating that, although mechanical grip has increased, some driving feel is lost and there is added bumpsteer. (check Excellence)
well isn't added mechanical grip a performance gain?
FWIW, not sure why mechanical grip is gained but they said it.
BTW, my sportecs (made by BBS) are heavier than my champion monolites but are NOT heavy. the kinesis f110 19" are 3~4 lighter than the 18" carrera lightweights so there's a performance gain there, yes?
re:997 tire sizes. there is still trickle down effect don't ya think? just like what happened with 18" tires. more and more car makers/wheel manufacturers are making 19" wheels and the tire manufacturers are catching up.
9ff and manthey racing chose do go with 18s instead of 19s stating that, although mechanical grip has increased, some driving feel is lost and there is added bumpsteer. (check Excellence)
well isn't added mechanical grip a performance gain?
FWIW, not sure why mechanical grip is gained but they said it.
BTW, my sportecs (made by BBS) are heavier than my champion monolites but are NOT heavy. the kinesis f110 19" are 3~4 lighter than the 18" carrera lightweights so there's a performance gain there, yes?
re:997 tire sizes. there is still trickle down effect don't ya think? just like what happened with 18" tires. more and more car makers/wheel manufacturers are making 19" wheels and the tire manufacturers are catching up.
- what do your sportecs weigh?
- do you know what they weigh in 18" fitments?
- do you have an option of forged or cast for these wheels?
thanks -- they are a great looking wheel, but I wouldn't consider them unless they were lighter than the stock Carrera lightweights (~20lb front, ~21 rear)