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Car Tyre size. Advice please????

Yank said:
I think the Michelin Pilot Supersport is the pick of that class of tire.
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Yup, I replaced my run flats on a 335i with Michelin Pilot Supersports and they are great. Improved the ride quality massively whilst keeping the grip and roll characteristics of the original setup. Quieter as well.

My tyres are the same as yours pretty much being 30 and 35 profile on 19" rims
 
Thanks all for your help. You never fail :D

Set of Michelin Pilot Supersport ordered & will be fitted next week, just in time for my return.

Got a 200+ mile journey to do straight away so I'll see if I can tell the difference.


ta!
 
strummer said:
Thanks all for your help. You never fail :D

Set of Michelin Pilot Supersport ordered & will be fitted next week, just in time for my return.

Got a 200+ mile journey to do straight away so I'll see if I can tell the difference.
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Looking forward to the report.
 
Anh said:
All decent tyres perform the same.

Just like audiophile equipment.
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I'll bite.

Not even close to audio. Tyres have very measurable benefits, braking distances, lateral grip, wet performance, noise etc etc.

Car mags regularly test top, med and low end tyres with many surprises with many "high" end tyres performing badly and cheaper brands often outperforming better known manufacturers.

Tyres are made for many different benefits with low rolling resistance rubber for economy all the way to super sticky track day semi slicks for ultimate performance. I tried some Toyo track day tyres on a mates 911 and it transformed the car from a performance road car to a track monster with huge levels of grip and braking. Only lasted a day but fun whilst they did.
 
cutting42 said:
I'll bite.

Not even close to audio. Tyres have very measurable benefits, braking distances, lateral grip, wet performance, noise etc etc.

Car mags regularly test top, med and low end tyres with many surprises with many "high" end tyres performing badly and cheaper brands often outperforming better known manufacturers.

Tyres are made for many different benefits with low rolling resistance rubber for economy all the way to super sticky track day semi slicks for ultimate performance. I tried some Toyo track day tyres on a mates 911 and it transformed the car from a performance road car to a track monster with huge levels of grip and braking. Only lasted a day but fun whilst they did.
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The driver and road condition makes the biggest difference, 2 perfectly functioning sets of tires from brand y and x with optimal geometry of suspension will be the same.

Magazine tests are next to worthless when comparing performance as they are tested in controlled environments and pushed and held at the limit of 'grip-slip' which 99% of petrolheads would end up in the ditch or armco. The heralded differences in cornering G, laptimes, braking distances are predominatley at the mercy of the skilled driver's abilty to manage the hysterisis.


It is how the tyre behaves at the limit which should never be flirted around with on the road that somehow gets translated to head line lap times and skid pad figures, with photos of F1 drivers and skantly clad women to sex up a boring cosumerable component of a motorcar.
 
Anh said:
The driver and road condition makes the biggest difference, 2 perfectly functioning sets of tires from brand y and x with optimal geometry of suspension will be the same.
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I can tell you that Pirelli PZero and Bridgestone RE050a feel massively different on my car. In fact, when I first mounted the Pirellis, I thought they were under-inflated. They felt soft and a bit imprecise in steering feel. I binned them well before they were worn. The Bridgestones, which are OEM specified for my car, felt immediately more alive.
 
Cars are designed with a particular tyre in mind, mine works with Pirelli Zero Rossos because they are closest to original spec, i've tried a few over the last 20 years and the only better tyre was Yokohama 008Ps. But they only lasted 4k miles.
 
A visit to Kwik Fit a few weeks ago to replace my front Mitchelin Energy tyres after 25,000 miles on my Volvo V70 at a cost of £85 (price matched from £105) and was interested to see their new gadget the electronic wheel alignment adjuster. The display in the waiting room was showing an out of tolerance of 1 minute. I would be surprised if the measuring gear was accurate to measure a minute of inaccuracy.

The guy paid £40 for the test and £25 for the correction. This sound very much like the kwik fit of a few years ago where they tried to flog everyone shock absorbers.
The tyres he was having fitted were £400 each.
 
£400 each? Erm. Rip off? I'd NEVER go to Kwik Fit, even for some £50 cheapies. I'd rather walk.
 
All the rapidfit places work on job creation. You are right, the laser alignment things aren't accurate to a minute of arc. In any case the general tolerance is +/1 half a degree, so if the setting is (say) 1 deg toe in +/- 30 min, 1 minute over that is neither here nor there. It will however change the feel of the car if you are at one extreme or the other of the tolerance, a Caterham of mine was very steady set to max toe-in, very darty and easy to turn in when toed out, and parallel gave (no surprise) something in between. As to tyres all feeling the same, no they don't. Not even a bit. Around town, maybe, but when you are pressing on a bit, no chance.
 
I think Michelin did a survey about 15 years ago and found that something like 90% of drivers never exceed 50% of a tyre's ability. Perhaps some forum members fall into that category?
 
Tony Lockhart said:
I think Michelin did a survey about 15 years ago and found that something like 90% of drivers never exceed 50% of a tyre's ability. Perhaps some forum members fall into that category?
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Agreed.

Anh said they are all the same, clearly they are not. BUT, when used by the average user in A to B travelling, they will mostly act in a similar way and would hard to distinguish by the average driver.

To address Anh's other comments It is not necessary to be pushing hard at the limits of adhesion to tell the difference. The subtleties of turn in and braking traction can be felt well within speed limits and normal considerate road use. Not to mention noise and ride comfort is far more sensitive at low speeds.

I agree some magazine tests on laptime can seem irrelevant (unless for a track day tyre) but they are often done as a part of an overall subjective measurement from the reviewer and do not rely purely on the lap time as the judgement. However I have read some US car magazines and they really do go nuts on the numbers measuring everything and ignoring the subjective.
 
Agreed.

Do US car mags still emphasise constant radius cornering tests? Almost pointless really.
 
Tony Lockhart said:
Agreed.

Do US car mags still emphasise constant radius cornering tests? Almost pointless really.
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Not sure if they do any more as I tend to avoid them these days. It was this test that made US performance cars have such brutally hard suspension to generate the max G force.

I was always amazed at the results they got. My flabber was completely gasted when I read a test putting the Mazda 3 ahead of the Subaru Impeza WRX in terms of performance and handling :eek:
 
cutting42 said:
My flabber was completely gasted when I read a test putting the Mazda 3 ahead of the Subaru Impeza WRX in terms of performance and handling :eek:
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Must have been the Mazdaspeed3 then. And it would indeed outperform a standard WRX. On tarmac anyway.

As for skidpad numbers, that's just one spec on a page full of numbers, there hasn't been any particular undue emphasis on that in a car's overall rating since sometime in the 1980s.
 
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