17" to 18" Is it worth it?
04-29-2005, 01:02 AM
#17
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Originally Posted by FisterD
18's for me too. I like the look and the ride is still fine.
As far as tire prices, just got all 4 for $550. Dunlop SSR's.
As far as tire prices, just got all 4 for $550. Dunlop SSR's.
yeah, that price was too hard to walk away from given the price of michelin Pilot Sport cups in comparison.. $129 vs. $304 for one rear tire... hmmmmm
...unemployeed and 18" R compound Sport Race tires for $550? No contest!
I'll probably wish I had my pilot sport cups when I use them but such is life.. cost is a HUGE factor for me this race season!
04-29-2005, 03:43 AM
#18
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Originally Posted by robroy72
Looking at the pic in your avataar, if that is your car, aren't those 18" turbo twists on there already?
04-29-2005, 09:29 AM
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Some would disagree on the performance merits of 18" over 17" and the reultant decrease in tire profile. Barry Lake, writing for the Australian magazine Motor some years back (I am not exactly sure but I am guessing circa December 1998) discussed the trend to increasing wheel diameters and lower tire profiles with Yoshihiko Ichikawa the then technical manager for Bridgestone Motorsport UK and the design team leader of Bridgestone tires for the Honda NS-X, and Kazuo Shimizu a Japanese rally and touring car champion with supposedly 2000 plus laps around the Nurburgring testing tyres. Here are some of their opinions:
* Ichikawa and Shimizu believed that the trend to lower tire profiles in expensive performance cars was driven by fashion.
* Ichikawa was of the view that if F1 regulations allowed freedom of size that the desire would be for tires that were wide and tall to gain maximum footprint and therefore grip, but that a compromise would have to be found as this would create problems with aerodynamic drag. The only reason he saw for having a larger diameter wheel and hence lower tire profiles was to fit larger brakes inside the wheel.
* Ichikawa believed that the ideal tire profile for road cars was 50 to 60 series, and that once you get to 40, 35 and 30 series you have to “throw away all the sidewall stiffness to get reasonable ride”. Shimizu agreed saying that the then latest ultra-low profile tires had so little sidewall stiffness that cars moved all over the place at high cornering speed.
* Ichikawa and Shimizu believed that the trend to lower tire profiles in expensive performance cars was driven by fashion.
* Ichikawa was of the view that if F1 regulations allowed freedom of size that the desire would be for tires that were wide and tall to gain maximum footprint and therefore grip, but that a compromise would have to be found as this would create problems with aerodynamic drag. The only reason he saw for having a larger diameter wheel and hence lower tire profiles was to fit larger brakes inside the wheel.
* Ichikawa believed that the ideal tire profile for road cars was 50 to 60 series, and that once you get to 40, 35 and 30 series you have to “throw away all the sidewall stiffness to get reasonable ride”. Shimizu agreed saying that the then latest ultra-low profile tires had so little sidewall stiffness that cars moved all over the place at high cornering speed.
04-29-2005, 10:35 AM
#20
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I have 18" hollow turbo twists...stick with the 17's. Street handling improvement will hardly be noticed, but potholes, rough roadsm bumps, etc. will cause the ride to be worse and the potential for wheel/tire damage to increase exponentially.
04-29-2005, 10:44 AM
#21
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I have the Model Year 02 996 Lightweight 5 spokes and love them--traded up from my 17" Cups. The car looks a ton better. I would do it, and it sounds like you are getting a really good deal on hollow spokes--if you don't like them you can sell them, make a profit, and go back and buy 17s again.
04-29-2005, 11:28 AM
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interestingly enough, we noticed better performance on the track with the 18s vs. the 17s back to back with the same michelin pilot sport cup tires being the same age... (since we have his and hers 993s.. we started out the season last year with me being on 18s and him being on 17s)... even though his 17" kinesis weighed less then my 18" fikse (by a small margin), the performance feel at the same track was noticable with the 18s vs. the 17s... granted I'm guessing some of the noticable difference was due to the difference in rear tire fitment...
...although both front wheels/tires were 225s (225 45 17 vs. 225 40 18s) the rear tires were vastly different being 255 40 17 vs 285 30 18s..
You can simply stuff more tire and maintain proper ride height with the 18s... and there are plenty of 18" r compound tires available now..
Interestingly enough, I just drove a brand new 997 S at the track earlier this week and it had huge 19" wheels with Michelin PS2 tires (no R compounds available in 19" yet).. and I was very impressed with the car overall at the track.. I have no idea how 18s or 17s (if they even fit over the big brakes) would compare...
...although both front wheels/tires were 225s (225 45 17 vs. 225 40 18s) the rear tires were vastly different being 255 40 17 vs 285 30 18s..
You can simply stuff more tire and maintain proper ride height with the 18s... and there are plenty of 18" r compound tires available now..
Interestingly enough, I just drove a brand new 997 S at the track earlier this week and it had huge 19" wheels with Michelin PS2 tires (no R compounds available in 19" yet).. and I was very impressed with the car overall at the track.. I have no idea how 18s or 17s (if they even fit over the big brakes) would compare...
04-29-2005, 12:51 PM
#24
Race Director
Originally Posted by mborkow
"the trend to lower tire profiles in expensive performance cars was driven by fashion"
100%. this all about aesthetic.
100%. this all about aesthetic.
proof of the pudding: Escalades with 22" rims.
04-29-2005, 05:11 PM
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I have both and feel the 17's ride much better.
04-30-2005, 12:49 AM
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I have 18's for street and my stock 17's for track. I agree with Viken that my 17s handle better (with/without track tires). However, I'm interested in something Viken said about our cars not being "tuned" for larger tires. Viken, do tell, is there a DIY or instructions for our mechanic that would help tune the car for the larger tires? I already bought the steering column brace.
04-30-2005, 01:13 AM
#29
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I ordered mine with the car. I would get a ride on each before you commit. Impossible to get a true feel just from comments here. Upside, as stated, are looks and handling. Downside is be careful of potholes and tire costs. I love mine.
04-30-2005, 06:03 AM
#30
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If you can, try a 993 with 18s and see how you feel.
18s definitely have the hasher ride.
If I had 17s twists, I probably would not be too concerned to change to the 18s.
But true, they do look better.
18s definitely have the hasher ride.
If I had 17s twists, I probably would not be too concerned to change to the 18s.
But true, they do look better.
