Runflats vs non-runflats top speed
06-22-2010, 02:20 PM
#1
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Runflats vs non-runflats top speed
Hi, I'm from the Netherlands and I tested my C5's top speed on the German autobahn with the OEM runflats but I have a question if I switch to non-runflats (Michelin PS2). Is there any difference in the cars top speed when you put non runflats on the car compared to runflats (stiffer side wall, weight or more rolling resistance ect.) or is there zero change of my top speed?
06-22-2010, 03:20 PM
#2
Safety Car
Soooooooooo.... you tested your top speed on the Autobahn?? You lucky b@#^^%&! How fast did you get it up to? OEM run flats are highest speed rating, but some tires may have less rolling resistance and may give you a bit more... interesting question... I'd like to know too!
06-22-2010, 03:23 PM
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I have the 3.15 auto C5 with only the ziptie mod, I got up to 176mph (GPS'd!)felt it had a little bit more but I had to brake because someone in front of me was doing only 125mph lol
06-23-2010, 09:13 AM
#7
Tech Contributor
06-23-2010, 09:18 AM
#8
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A "W" speed rating is for speeds up to 168, and the "Y" rating is for speeds up to 186.
Btw, those ratings (as with ALL tires) are for the SUSTAINED speeds indicated, due to the heat generated. If you were to take a "W" rated tire up to 175 or 180, but did not keep it there very long (say for a few seconds), you would be fine. Just don't KEEP it there for any extended time and expect the tire to stay together. Same for the "Y" rated tires.
HTH
06-23-2010, 09:38 AM
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That would be fun to do. I doubt if a different tire would make a lot of difference.
?
06-29-2010, 09:53 PM
#15
Safety Car
Looks like you didn't get the answer you're looking for...prob have to talk to some raod racers or maybe some tire mamufacturers and see if they have that type of data... i'm sure it exists....just trying to find it is going to be tough...every year there's a bunch of guys in Nevada that do top speed runs on a closed section of highway in the desert .... they look for every last bit of top speed... tires can be an issue there, and some of them may know which one'shave less rolloing resistance (if there is any)..but good luck tracking it all down...
06-29-2010, 10:05 PM
#16
Team Owner
Looks like you didn't get the answer you're looking for...prob have to talk to some raod racers or maybe some tire mamufacturers and see if they have that type of data... i'm sure it exists....just trying to find it is going to be tough...every year there's a bunch of guys in Nevada that do top speed runs on a closed section of highway in the desert .... they look for every last bit of top speed... tires can be an issue there, and some of them may know which one'shave less rolloing resistance (if there is any)..but good luck tracking it all down...
06-29-2010, 11:15 PM
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The weight of the tire should only affect the acceleration. More tire mass means it takes longer to get to top speed.
My guess would be that a good non run-flat performance summer tire might be just a wee bit slower but you'd likely hardly notice. As already pointed out, the main thing holding you back is the aero drag.
On another note, unless you get a better deal on PS2's than we do in North America, I think PS2's are too much $$$ for the tire. Sure, lots of guys swear by them. However, I think it's mostly because when they are so pricy they just have to be the best, right??
?? ??
There are other tires that would work just as well. I've got Bridgestone RE-11's on the front and they're going on the rear next. About 60% of the cost of PS2's in my 19" sizes. The only downsides are the W speed rating but I have no place I can go >168mph and they weight a few pounds more each so the car will accelerate slightly slower but I'm OK with that since they still weigh less than the stock runflats weigh
Peter
My guess would be that a good non run-flat performance summer tire might be just a wee bit slower but you'd likely hardly notice. As already pointed out, the main thing holding you back is the aero drag.
On another note, unless you get a better deal on PS2's than we do in North America, I think PS2's are too much $$$ for the tire. Sure, lots of guys swear by them. However, I think it's mostly because when they are so pricy they just have to be the best, right??
?? ??There are other tires that would work just as well. I've got Bridgestone RE-11's on the front and they're going on the rear next. About 60% of the cost of PS2's in my 19" sizes. The only downsides are the W speed rating but I have no place I can go >168mph and they weight a few pounds more each so the car will accelerate slightly slower but I'm OK with that since they still weigh less than the stock runflats weigh
Peter
