Tyre Pressure recommended...
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lozcb
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TheBeagler
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The technical papers says 2bars for all four ...
Grinzzz
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I think i can count on one hand the number of cars I've had where the manufacturers recommended pressures were the right ones. Not sure what they play at but I suspect an alliance with tyre manufacturers to ensure tyres get worn faster!
Not had time to do the maser but there are, for me, two ways to get the the "right" pressure. Long term way is to ensure you inflate to the same pressure for a long time and basically look at the wear pattern. If the wear is even from inside to out it's the right pressure. if its worn more on either the centre or BOTH edges its over or under inflated respectively. Takes ages to find it out though.
Quick way is to get on track and get those tyres really warm and then dash back into the pits and have someone stick a tyre temperature probe in across the tyres. Temp change inside to outside should be even. If its higher in centre then overinflated etc. Once you've got it right let the tyres cool and test the pressure. Note that the temp won't be the same across the tyre - the camber generally means the inside wil be warmer than the outside. But at optimum pressure the temp change should be "even" across the tyre.
Basically what the above do is ensure you have the optimum contact patch between the tyre and the road - this gives the max chemical bonding and hence most grip. Grip is good.
Once you've got the "right" pressure established I tend to play around either side by just a couple of psi to see if the car feels any better either side of the optimum. I'll do things like drop the front a couple of psi and raise the rears a couple (and vice versa) to see if it improves turn in.
This works for me - even if being a bit OTT
Not had time to do the maser but there are, for me, two ways to get the the "right" pressure. Long term way is to ensure you inflate to the same pressure for a long time and basically look at the wear pattern. If the wear is even from inside to out it's the right pressure. if its worn more on either the centre or BOTH edges its over or under inflated respectively. Takes ages to find it out though.
Quick way is to get on track and get those tyres really warm and then dash back into the pits and have someone stick a tyre temperature probe in across the tyres. Temp change inside to outside should be even. If its higher in centre then overinflated etc. Once you've got it right let the tyres cool and test the pressure. Note that the temp won't be the same across the tyre - the camber generally means the inside wil be warmer than the outside. But at optimum pressure the temp change should be "even" across the tyre.
Basically what the above do is ensure you have the optimum contact patch between the tyre and the road - this gives the max chemical bonding and hence most grip. Grip is good.
Once you've got the "right" pressure established I tend to play around either side by just a couple of psi to see if the car feels any better either side of the optimum. I'll do things like drop the front a couple of psi and raise the rears a couple (and vice versa) to see if it improves turn in.
This works for me - even if being a bit OTT
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Grinzzz
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Actually I did think of something else - sidewall stiffness. I've never run P-zeros on a track but I have noticed that a lot of cars have tyres where the sidewalls are too soft for the car weight. When this happens you can see the car leaning over on it's sidewalls. The "solution" without finding better tyres is to go for a large increase in pressure to effectively increase the stiffness.
Anyone know if the p-zeros suffer from this? It normally only shows up on track or if you're into very "spirited" driving in the twisty bits.
Anyone know if the p-zeros suffer from this? It normally only shows up on track or if you're into very "spirited" driving in the twisty bits.
NZSpyder
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Hi , sorry to be a pain.I have looked through here but couldn't really find a definitive answer ( I know personal preference plays a part ) However would just like to check with someone with some more miles under the belt.Reccommended pressure seems a bit light to me but within reason what is it safe to run with on the following ? 2002 Spyder , Dunlop sp sport maxx, Front 235/40zr 1895y, Rear 265/35zr1897y. Thanks
hodroyd
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My Assetto Corsa documentation includes 2 tyre pressure spec sheets. The earlier one gives a pressure front and back of 1.8 Bar, normal load on P Zero Corsa, the later one changed this to 2.1 Bar front and 2.0 Bar at the rear for the P Zero. Michelin were 2.0 bar all round. This would maybe answer the question about tyre walls, sounds as though P zero's may be slightly softer. I keep mine at 2 Bar for normal running on P Zero, I might just try 2.1 on the front to see how they perform. Over inflation is risky for central tyre life, if you burn off the centre section and don't notice, you risk an unsafe ride, thinking the shoulders look good with plenty of meat on, but in reality you only have maybe two thirds of normal grip.