Tracking your 997GT3 - TAKE NOTE
Discussion
After reading of the untimely puncture of the 997GT3 during this years ECOTY, it struck me that I should pass on some advice to any owners or potenial owners of 997GT3's who intended to track thier cars.
The MSCup tyre is an amazing track tyre. We found that it works best at 2.1 bar all round hot on the circuit. During a track day a driver should constantly 'bleed off' his tyres to keep them at 2.1 bar. Ultimately they will reach optimum temperature and the pressure will remain constant with no further bleeding required. On a warm day, an experienced driver will get his or her tyres to optimum temperature after about 3 or 4 laps, an inexperienced driver could take 10 or 20.
IT IS ESSENTIAL to re-inflate your tyres immediately before you leave the circut at the END OF THE DAY and after the tyres have cooled a little - say 30 mins. As the air in the tyre cools, the pressure drops. If you do not re-inflate your tyres to the reccommended road pressures you have a high risk of tyre failure due to under inflation. The sidewall of the Mscup is very soft and relys on air pressure for much of it's strength. Without it, you are in big trouble. The left rear has generally the highest risk as it does most of the work on most circuits and consiquently will have most air bled from it. I know of several drivers who have been caught out by this and have had left rear tyre failure, generally it happens in the morning after a track day when the air in the tyre is cold and pressure is at it'd lowest.
This is absolutely NOT a fault with the tyre, it is a driver error. The MSPcup is - in my opinion - the best legal track orientated tyre for the GT3 by far and gives an amazing performance on the track.
Just remember, after the track day, re inflate your tyres..
Steve R
The MSCup tyre is an amazing track tyre. We found that it works best at 2.1 bar all round hot on the circuit. During a track day a driver should constantly 'bleed off' his tyres to keep them at 2.1 bar. Ultimately they will reach optimum temperature and the pressure will remain constant with no further bleeding required. On a warm day, an experienced driver will get his or her tyres to optimum temperature after about 3 or 4 laps, an inexperienced driver could take 10 or 20.
IT IS ESSENTIAL to re-inflate your tyres immediately before you leave the circut at the END OF THE DAY and after the tyres have cooled a little - say 30 mins. As the air in the tyre cools, the pressure drops. If you do not re-inflate your tyres to the reccommended road pressures you have a high risk of tyre failure due to under inflation. The sidewall of the Mscup is very soft and relys on air pressure for much of it's strength. Without it, you are in big trouble. The left rear has generally the highest risk as it does most of the work on most circuits and consiquently will have most air bled from it. I know of several drivers who have been caught out by this and have had left rear tyre failure, generally it happens in the morning after a track day when the air in the tyre is cold and pressure is at it'd lowest.
This is absolutely NOT a fault with the tyre, it is a driver error. The MSPcup is - in my opinion - the best legal track orientated tyre for the GT3 by far and gives an amazing performance on the track.
Just remember, after the track day, re inflate your tyres..
Steve R
Koln-RS said:
ianmcg said:
Is the MSPCUP in 18" 996GT3 fitment the same technology as the 19" 997 GT3? For some reason I though the newer one is a different compound?
Pretty sure it's an evolution - designed for road and track with improvements to wet performance, longer life, quieter ride.
Same compound, deeper grooves
Steve R
I have never done that in the last 3 years but should maybe start. Normally just turn take 2or 3laps to warm the tyes up and come and check and they are spot on 31 , then drive car normally, next track day warm up check and they are back at 31. But when taking the old tyres of at the end of the season Noticed that the canvas was showing on the inner edge of the left rear. The problems are mainly due to the increased camber used by trackdayers thus it will not be such an issue with the new car unless the set up altered but good advice nonetheless
Pork_n_Beem said:
Gosh is that true, i thought all gases increased their volume with temperature and as such place an increase in pressure in the tyre.
How does Nitrogen do it.... for the scientists was thinking about PVT, going back 25 years mind when i was at college.
How does Nitrogen do it.... for the scientists was thinking about PVT, going back 25 years mind when i was at college.
Your memory hasnt failed you yet ALL gases expand when they are hot.
IIRC the advantages for having Nitrogen filled tyres is there is no moisture in the Nitrogen so teh pressures dont fluctuate as much due to atmospheric changes. I could be wrong though!
steve rance said:
Just remember, after the track day, re inflate your tyres..
Steve R
I forgot to do this last week at Cadwell, luckily my tyres didn't fail on the way home, but point taken well and truly.
Some of you also might find this download interesting. Someone posted it on bm3w a week or so back and its full of info about longevity and performance from MPCS's.
[url]www.tirerack.com/tires/tiretech/general/Michelin_Care_and_Feeding.pdf[/url]
You are correct DP. Nitrogen doesn't contain moisture and is therefore less prone to temperature fluctuations.
A lot of F1 and other race teams use dry nitrogen gas to inflate their tyres instead of air. This is done for two reasons. Firstly the moisture content of air is variable depending on the local weather conditions and this differs considerably between some of the exotic locations. By using dry nitrogen gas the tyres will behave in a predictable way wherever they are being used. The second reason is that air is a mixture of nitrogen (78%) and oxygen (21%). Oxygen gas is far more reactive than nitrogen and at the high operating temperatures of f! tyres (over 100c)the oxygen reacts with the tyre, reducing the total pressure inside. Using pure nitrogen removes this problem and tyre pressures remain far more consistent.
Quiet a few places can provide it.
A lot of F1 and other race teams use dry nitrogen gas to inflate their tyres instead of air. This is done for two reasons. Firstly the moisture content of air is variable depending on the local weather conditions and this differs considerably between some of the exotic locations. By using dry nitrogen gas the tyres will behave in a predictable way wherever they are being used. The second reason is that air is a mixture of nitrogen (78%) and oxygen (21%). Oxygen gas is far more reactive than nitrogen and at the high operating temperatures of f! tyres (over 100c)the oxygen reacts with the tyre, reducing the total pressure inside. Using pure nitrogen removes this problem and tyre pressures remain far more consistent.
Quiet a few places can provide it.
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