Need new rear tires...
09-16-2010, 01:57 AM
#52
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One of those tires would be the 265 Dunlop Direzza Star specs. Ive seen them next too a 275 Hoosier tire and they were pretty much the same width.
09-16-2010, 02:00 AM
#53
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Please elaborate from your experience.....
09-16-2010, 02:58 AM
#55
09-16-2010, 08:48 AM
#57
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2017 Mini Cooper S Clubman ALL4 - British Racing Green
There is a 1% speed difference in the fronts going from 235/40 to 245/40
And a 2% speed difference in the rears going from 255/35 to 275/35.
Wheel speed sensor that the car uses for the speedo.. is on the fronts or the rears?
So.... For those who have changed from the OEM sizes to a completely different size, did you account for speed loss or gains, have the speedo recalibrated, etc...
I think I have completely derailed this thread....... sorry..
Last edited by jvanbrecht; 09-16-2010 at 08:51 AM. Reason: Messed up the calculations, I need more caffiene
09-16-2010, 09:39 AM
#58
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2010 C63
09-16-2010, 10:09 AM
#59
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2012 C63;1971 280SE 3.5(Sold);2023 EQS 450 SUV 4 Matic (Wife's)
The speed sensor is usually on the transmission, so I am assuming this is true on the C63 because I don't actually know where it is. Anyway, the driven wheels are the rear wheels on the C63 so they are the ones you use to calculate any speed difference caused by different sized tires.
Determining the exact speed difference may be more problematic due to the methodologies different tire manufacturers use to label their tires compared to the competition and to different tires in their own lineups.
Might try comparing RPM (revolutions per mile) listed on tire rack in the spec for each tire they sell.
or, time a measured mile on the highway driving as close to 60 mph as you can hold it. If the speedo is accurate the time will measure 60 seconds. Any variation from 60 seconds + or - can be used to calculate the speedo error.
Changing the speedo calibration in the tune may be possible but is probably not worth it for a 1% or 2% error. Just make a mental note that you are traveling faster of slower than the speedo is indicating and make a small adjustment to your speed to account for it.
Determining the exact speed difference may be more problematic due to the methodologies different tire manufacturers use to label their tires compared to the competition and to different tires in their own lineups.
Might try comparing RPM (revolutions per mile) listed on tire rack in the spec for each tire they sell.
or, time a measured mile on the highway driving as close to 60 mph as you can hold it. If the speedo is accurate the time will measure 60 seconds. Any variation from 60 seconds + or - can be used to calculate the speedo error.
Changing the speedo calibration in the tune may be possible but is probably not worth it for a 1% or 2% error. Just make a mental note that you are traveling faster of slower than the speedo is indicating and make a small adjustment to your speed to account for it.
09-16-2010, 02:14 PM
#60
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2017 Mini Cooper S Clubman ALL4 - British Racing Green
After running myself in circles over what tires to get.. I decided to just get 2 rears (265/35ZR18 Continental ExtremeContact DW). Hopefully they will wear out right around the time that the front Pzero's wear out. At which point I will switch to DWS all seasons and pickup a set of cheap rims with tires for track purposes. Since my car is going in for service as well, I did not want to spend too much on 4 wheels to switch to the all seasons for fear of my wifes wrath..... So I went with 2 tires.
Thought about going 275, but it was almost $100 more for 2 tires over the 265, and honestly, I doubt I would notice the difference much.
Thought about going 275, but it was almost $100 more for 2 tires over the 265, and honestly, I doubt I would notice the difference much.
09-16-2010, 02:43 PM
#61
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After running myself in circles over what tires to get.. I decided to just get 2 rears (265/35ZR18 Continental ExtremeContact DW). Hopefully they will wear out right around the time that the front Pzero's wear out. At which point I will switch to DWS all seasons and pickup a set of cheap rims with tires for track purposes. Since my car is going in for service as well, I did not want to spend too much on 4 wheels to switch to the all seasons for fear of my wifes wrath..... So I went with 2 tires.
Thought about going 275, but it was almost $100 more for 2 tires over the 265, and honestly, I doubt I would notice the difference much.
Thought about going 275, but it was almost $100 more for 2 tires over the 265, and honestly, I doubt I would notice the difference much.
09-16-2010, 03:09 PM
#62
MBWorld Fanatic!
After running myself in circles over what tires to get.. I decided to just get 2 rears (265/35ZR18 Continental ExtremeContact DW). Hopefully they will wear out right around the time that the front Pzero's wear out. At which point I will switch to DWS all seasons and pickup a set of cheap rims with tires for track purposes. Since my car is going in for service as well, I did not want to spend too much on 4 wheels to switch to the all seasons for fear of my wifes wrath..... So I went with 2 tires.
Thought about going 275, but it was almost $100 more for 2 tires over the 265, and honestly, I doubt I would notice the difference much.
Thought about going 275, but it was almost $100 more for 2 tires over the 265, and honestly, I doubt I would notice the difference much.
09-17-2010, 12:57 PM
#65
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2017 Mini Cooper S Clubman ALL4 - British Racing Green
So, I just looked at my tires, closer inspection... They are 235/40 all around. Before I just looked at the tread, that would explain why my traction sucked. After all my comments and questions, you would think I was more observant... Oh well, ordered my tires yesterday, and the are already here... Tirerack shipping is awesome.
