So what have you done with your Aston today? (Vol. 2)
Discussion
I had my first service done today and whilst it was there the silver diamond cutting removed from my wheels. I always thought it looked odd, there's no silver anywhere else on the car and every other spoke and the very outer rim being silver made it look like it had huge/weird shaped wheels from any distance. Much better all black!
My health check also picked up on my rear tyres being down to 2mm. I've only done 3.5k miles in the car, so that's a new (expensive) record for me. I guess I should look after the new tyres a little more!
Before:
During:
After:
Can't wait to see it out in the daylight now, only picked the car up this evening and the weather was terrible
My health check also picked up on my rear tyres being down to 2mm. I've only done 3.5k miles in the car, so that's a new (expensive) record for me. I guess I should look after the new tyres a little more!
Before:
During:
After:
Can't wait to see it out in the daylight now, only picked the car up this evening and the weather was terrible
Edited by Shrimpvende on Wednesday 16th December 23:55
Shrimpvende said:
Very Gulf! 
I agree with you, the full black wheels are way more "right". Similarly, I hunt down colours that don't belong on the car; I even had the two Euro strips on the license plate in black instead of blue to make it match better.
krisdelta said:
I'm 100 miles into fresh PS4S tyres, which are life changing coming off the Bridgestones - much calmer ride, loads more grip and more comfortable. £710 all-around, bargain I think!
I will be in this situation next week, just ordered them. I really looking forward for better comfort, that Sport Pack on old Bridgestones is killing me, especially downtown Milan on the pavé/cobblestone historic streets.
Joined the club of the Michelin PS4S!
I then drove it around 30 km, I must say the difference in comfort (so far) from beat up Bridgestone is... not the night & day I was hoping.
I might have been a victim of the hype. Sure, the car feels more planted, lighter steering, solid braking, comfort-wise it feels better but not by an enormous amount. I think the transformation might be more evident on non Sport Pack cars maybe? But the jury is still out.
Another thing, my tyre shop inflated them with nitrogen instead of air, citing a plethora of benefits for sports cars (lighter, less hotter, less moist and more stable than air). What do you guys think of this?
I then drove it around 30 km, I must say the difference in comfort (so far) from beat up Bridgestone is... not the night & day I was hoping.
I might have been a victim of the hype. Sure, the car feels more planted, lighter steering, solid braking, comfort-wise it feels better but not by an enormous amount. I think the transformation might be more evident on non Sport Pack cars maybe? But the jury is still out.
Another thing, my tyre shop inflated them with nitrogen instead of air, citing a plethora of benefits for sports cars (lighter, less hotter, less moist and more stable than air). What do you guys think of this?
nitrogen instead of air? lighter, less hotter, less moist and more stable than air?
What is the amount and weight of „air“ in a tyre?
Let us assume that the volume of the space between rim and tyre would be 0.05 cubic meter.
And let us assume an pressure of 2.5 bar, than we would assume 0.175 cubic meter of air in an inflated tyre.
Assuming the weight of air to be approximately 1,290 g per cubic meter, than we talk of compressed 226 g air in an inflated tyre. Not that much.
The same volume of compressed nitrogen would have a weight of approximately 219 g – which is a significant saving of 7 g (admittedly per wheel!).
I think we do not need to discuss that this difference will not have any material impact on fuel consumption.
Less moist can be true. But is there a risk of rust in either carcass or rim? Definitely not. The carcass is protected by a layer of rubber and we use painted alloys. No benefit.
Stable? OK, nitrogen does not promote corrosion. But I never had any corrosion on my alloy wheels, nor on the tyre.
What about of loss of pressure? True, oxygen would „flow“ out three times faster than nitrogen through the sidewall of the tyre. But that is totally irrelevant since more than 90% of the pressure loss occurs from the valve! There is no migration through the rubber to a meaningful extent. But anyway I check my pressure occasionally (and the onboard diagnostic also) more to be sure there is no puncture. Anyway, this would not support the purchase of nitrogen.
Less moist is an issue with extremely hot tyres – in race cars. With increasing temperature moisture may expand stronger than nitrogen and lead to higher pressures. And that will impact the shape of the tyre and the foot print on the tarmac. Therefore race cars use nitrogen gas. Simply because the pressure of nitrogen filled tyres is fluctuating less than with moist air. Could make sense on a track day? Not really. On a track day the tyres get much hotter than on highway use. The pressure therefore would increase way beyond optimum values. You will need to reduce the pressure by 0.4 bar anyway and regardless of nitrogen or air filling. And when you leave the track you need to blow up again 0.4 bar (which you will do with simple and cheap compressed air close to the track). So the benefit of nitrogen is gone... Unfortunately we are not able to drive a tyre so consistent as a professional to benefit from the nitrogen advantages. Our lack of perfection will create higher pressure fluctuations than the filling medium.
It is just marketing: Does the selling for the tyre shop, adds significant incremental profit on every single tyre transaction!
What is the amount and weight of „air“ in a tyre?
Let us assume that the volume of the space between rim and tyre would be 0.05 cubic meter.
And let us assume an pressure of 2.5 bar, than we would assume 0.175 cubic meter of air in an inflated tyre.
Assuming the weight of air to be approximately 1,290 g per cubic meter, than we talk of compressed 226 g air in an inflated tyre. Not that much.
The same volume of compressed nitrogen would have a weight of approximately 219 g – which is a significant saving of 7 g (admittedly per wheel!).
I think we do not need to discuss that this difference will not have any material impact on fuel consumption.
Less moist can be true. But is there a risk of rust in either carcass or rim? Definitely not. The carcass is protected by a layer of rubber and we use painted alloys. No benefit.
Stable? OK, nitrogen does not promote corrosion. But I never had any corrosion on my alloy wheels, nor on the tyre.
What about of loss of pressure? True, oxygen would „flow“ out three times faster than nitrogen through the sidewall of the tyre. But that is totally irrelevant since more than 90% of the pressure loss occurs from the valve! There is no migration through the rubber to a meaningful extent. But anyway I check my pressure occasionally (and the onboard diagnostic also) more to be sure there is no puncture. Anyway, this would not support the purchase of nitrogen.
Less moist is an issue with extremely hot tyres – in race cars. With increasing temperature moisture may expand stronger than nitrogen and lead to higher pressures. And that will impact the shape of the tyre and the foot print on the tarmac. Therefore race cars use nitrogen gas. Simply because the pressure of nitrogen filled tyres is fluctuating less than with moist air. Could make sense on a track day? Not really. On a track day the tyres get much hotter than on highway use. The pressure therefore would increase way beyond optimum values. You will need to reduce the pressure by 0.4 bar anyway and regardless of nitrogen or air filling. And when you leave the track you need to blow up again 0.4 bar (which you will do with simple and cheap compressed air close to the track). So the benefit of nitrogen is gone... Unfortunately we are not able to drive a tyre so consistent as a professional to benefit from the nitrogen advantages. Our lack of perfection will create higher pressure fluctuations than the filling medium.
It is just marketing: Does the selling for the tyre shop, adds significant incremental profit on every single tyre transaction!
EVR said:
Joined the club of the Michelin PS4S!
I then drove it around 30 km, I must say the difference in comfort (so far) from beat up Bridgestone is... not the night & day I was hoping.
I might have been a victim of the hype. Sure, the car feels more planted, lighter steering, solid braking, comfort-wise it feels better but not by an enormous amount. I think the transformation might be more evident on non Sport Pack cars maybe? But the jury is still out.
Another thing, my tyre shop inflated them with nitrogen instead of air, citing a plethora of benefits for sports cars (lighter, less hotter, less moist and more stable than air). What do you guys think of this?
I found in my V12VSM that with the MPS4S’s on it is a lot less squirmy under hard acceleration (2nd or 3rd foot flat down used to lose the back even in the dry a little) now it just grips and goes. Very noticeable when driving spiritedly...I then drove it around 30 km, I must say the difference in comfort (so far) from beat up Bridgestone is... not the night & day I was hoping.
I might have been a victim of the hype. Sure, the car feels more planted, lighter steering, solid braking, comfort-wise it feels better but not by an enormous amount. I think the transformation might be more evident on non Sport Pack cars maybe? But the jury is still out.
Another thing, my tyre shop inflated them with nitrogen instead of air, citing a plethora of benefits for sports cars (lighter, less hotter, less moist and more stable than air). What do you guys think of this?
ReformedPistonhead said:
I found in my V12VSM that with the MPS4S’s on it is a lot less squirmy under hard acceleration (2nd or 3rd foot flat down used to lose the back even in the dry a little) now it just grips and goes. Very noticeable when driving spiritedly...
Will try an report!The thing about tyre changes is usually someone is changing from a set of used, near the bars, old tyres, to new, full tread tyres. It’s hardly surprising that people judge the new tyres to be so much better. I would like to know how PS4S tyres cope when there’s less than 3mm left on them compared to the BS or Pirelli options. But maybe this should be on another thread?
soofsayer said:
The thing about tyre changes is usually someone is changing from a set of used, near the bars, old tyres, to new, full tread tyres. It’s hardly surprising that people judge the new tyres to be so much better. I would like to know how PS4S tyres cope when there’s less than 3mm left on them compared to the BS or Pirelli options. But maybe this should be on another thread?
Correct but what I am saying is that comfort-wise, it was not the transformation I was maybe expecting, coming from Bridgestone that were probably from when the car was new (2011).But you are right, I will stop here talking about it and report back my findings in the tyre thread.
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