991 Track Speed/Feel difference 19s v 20s
#1
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Brethren, I have a track weekend scheduled at Sonoma next month and I'm contemplating picking up a set of rims specific for track days.
If there is not a great deal of difference I would lean towards some brushed silver 20s that could also be used to change the look of the GTS for everyday driving. This is secondary to performance, however.... For now.![Smilie](https://rennlist.com/forums/images/smilies/smile.gif)
Need some perspective - Driving ability aside, is there a noticeable difference that I would feel between 19s and 20s on the track? I would be running Michelin cup 2 tires on my GTS.
Thanks!
If there is not a great deal of difference I would lean towards some brushed silver 20s that could also be used to change the look of the GTS for everyday driving. This is secondary to performance, however.... For now.
![Smilie](https://rennlist.com/forums/images/smilies/smile.gif)
Need some perspective - Driving ability aside, is there a noticeable difference that I would feel between 19s and 20s on the track? I would be running Michelin cup 2 tires on my GTS.
Thanks!
#2
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I've tracked a 19 in wheeled base 991 as well my own 20 in wheeled base 991. The difference is noticeable to the point that I'm looking for the right 19 in wheels. Turn in is better, acceleration is better, even braking from very fast speeds is better. I think the 991 Cup and 991 RSR are both running 18 in wheels.
#3
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I'm very interested to learn from this, looking for wheels now specifically for the track. Searched Rennlist and it appears our cars do not support 18" wheels (the lower control arm fouls the wheel), if anyone has proof otherwise please speak up because that opens a much more affordable set of options.
I did purchase a two wheel trailer for hauling tools and tires to the track. Finished my hitch design, just need to finish building it (the milling machine is down at the moment) and will provide drawings and photos after the install if everything goes well.
I did purchase a two wheel trailer for hauling tools and tires to the track. Finished my hitch design, just need to finish building it (the milling machine is down at the moment) and will provide drawings and photos after the install if everything goes well.
#4
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I've tracked a 19 in wheeled base 991 as well my own 20 in wheeled base 991. The difference is noticeable to the point that I'm looking for the right 19 in wheels. Turn in is better, acceleration is better, even braking from very fast speeds is better. I think the 991 Cup and 991 RSR are both running 18 in wheels.
If anyone knows the size and specs of the 19" rim that would be able to fit in the 991 GTS I would appreciate the help....
#5
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Your wheel widths and ofsets will depend on what size tires you want to run.
Have you decided on what size tires you want to fit?
Also, what I heard was the inside barrel clearance, on rear wheel, can be tight on a 19, due to rear knuckle.
Choose a wheel with a very open barel design, in the rear. A stepped type barrel could be problematic.
Have you decided on what size tires you want to fit?
Also, what I heard was the inside barrel clearance, on rear wheel, can be tight on a 19, due to rear knuckle.
Choose a wheel with a very open barel design, in the rear. A stepped type barrel could be problematic.
#6
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Thanks for the feedback! Yes the Cup cars have 18s and perform best over the 19s. By how much - who knows. but I have read 18s will not fit over the stock GTS calipers. Your statement makes me believe a set of 19s would be best.
If anyone knows the size and specs of the 19" rim that would be able to fit in the 991 GTS I would appreciate the help....
If anyone knows the size and specs of the 19" rim that would be able to fit in the 991 GTS I would appreciate the help....
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BTW - we measured the calipers at my independent shop and it looks like 18's will fit, but we did not the check the lower control arm and based on what I've found here on RL that's where the problem is.
If I find anyone running 18's I report back exactly what their wheel/tire setup is.