Looking for a bit of advice on tyre pressures. I've just fitted a set of 15" alloys with 195/50/R15 82V Michelin tyres. I had a look at the sticker on the fuel filler cap door, doesn't have specific values listed for this tyre size. I've currently got them at 2.2bar at the front and 2.1bar at the back (trying to compromise between the listed values lol) but they still look a bit low. I'm undecided at the moment whether to raise them or not.
Can anyone give any advice on this? What pressures do you guys run at?
Cheers in advance
Tyre pressures?
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blazeguarder
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Re: Tyre pressures?
I would run the tyres at 35psi for comfort and 38 psi for grip / fuel economy.
This is 2.4 and 2.6 bar for you imperialists.
For lower profile tyres you can go higher, but higher PSI in bigger profile tyres does not seem to work as well IMO.
This is 2.4 and 2.6 bar for you imperialists.
For lower profile tyres you can go higher, but higher PSI in bigger profile tyres does not seem to work as well IMO.
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blazeguarder
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Re: Tyre pressures?
Excellent, thanks for the advice mate.
Will give it a go later.
Will give it a go later.
Re: Tyre pressures?
I have 2.4 bar in the front and 2.6 bar in the rears. Tyres are 205/45/16
Re: Tyre pressures?
Why run the rears with more pressure?
Each to their own, but I think the rear should have less pressure as there is much less weight over the rear wheels. This keeps the ride soft (but then again, my ride is very tight).
Each to their own, but I think the rear should have less pressure as there is much less weight over the rear wheels. This keeps the ride soft (but then again, my ride is very tight).
Re: Tyre pressures?
makes sence.
the back wheels are just following the front wheels and have no direct traction.
the harder the back wheels are, the less power the engine got to use to drag them.
if the rear tyres are flatter, the engine has to do more work, fuell economy will go up also.
as for cornering, if the fronts are on 2.2 - 2.4 bar and the back ones are on 2.4 - 2.6bar you will create a bit lift off oversteer when you realy push it.
easier to drive as understeer IMHO.
also in a straight line like a dragrace i sometimes put my front tyres on 1.8bar, gives really great grip!
i'm sure you will beat your personal 0-60record without any doubt
but, once after 60mph you don't need grip anymore and you will have more drag and will go slower as when youre tyres are on 2.4bar.
but on 2.4bar you won't go as fast to 60.
you have to compromise.
1.8bar is excellent for 1/8mile dragrace, for a 1/4mile tyres are better on 2 - 2.1 bar or so. (not good for daily use)
depends also on tyre choise and the tarmac you drive on.
the back wheels are just following the front wheels and have no direct traction.
the harder the back wheels are, the less power the engine got to use to drag them.
if the rear tyres are flatter, the engine has to do more work, fuell economy will go up also.
as for cornering, if the fronts are on 2.2 - 2.4 bar and the back ones are on 2.4 - 2.6bar you will create a bit lift off oversteer when you realy push it.
easier to drive as understeer IMHO.
also in a straight line like a dragrace i sometimes put my front tyres on 1.8bar, gives really great grip!
i'm sure you will beat your personal 0-60record without any doubt
but, once after 60mph you don't need grip anymore and you will have more drag and will go slower as when youre tyres are on 2.4bar.
but on 2.4bar you won't go as fast to 60.
you have to compromise.
1.8bar is excellent for 1/8mile dragrace, for a 1/4mile tyres are better on 2 - 2.1 bar or so. (not good for daily use)
depends also on tyre choise and the tarmac you drive on.
Re: Tyre pressures?
Indeed. Track cars tend to run stiffer springs at the back and more air in the tyres to get a quicker turn-in and less body roll, but on road car, the rear should always be setup softer than the front for safety, otherwise lift off oversteer can become very unpredictable in the wet. I've been that man. I was messing about with spring rates at the back and tyre pressures and did a full 360 spin on a wet roundabout at only 30mphnoone025 wrote:Why run the rears with more pressure?
Each to their own, but I think the rear should have less pressure as there is much less weight over the rear wheels. This keeps the ride soft (but then again, my ride is very tight).
Tyre pressures, I find 34 psi front (cold) and 30psi rear works well for our GTI. A good compromise between keeping the contact patch flat to the tarmac and ride comfort. Any more than that and you can end up wearing the middle of the tread down if you don't do a lot of beefy cornering, which is what I've found at least.
Re: Tyre pressures?
Mine are 2.4 front, 2.6 rear because it on the inside of the petrol flap, that is all. 
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blazeguarder
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Re: Tyre pressures?
Thanks for all the replies guys. Really appreciate the help.
Got it up to 2.5 bar front and 2.4 bar rear earlier, went for a drive and the car definitely felt sharper in the corners and when cruising. Don't know if it's just me or if it's finally having the same tyre all round! Well pleased though
Got it up to 2.5 bar front and 2.4 bar rear earlier, went for a drive and the car definitely felt sharper in the corners and when cruising. Don't know if it's just me or if it's finally having the same tyre all round! Well pleased though
Might be the values with 4 passengers and luggage? Tbh though, it's your car, if you're happy with it then leave it as it is!Gillen wrote:Mine are 2.4 front, 2.6 rear because it on the inside of the petrol flap, that is all.