I have been gradually increasing my tyre pressures to find the results. I started at f32 r30, i have now got to f38 r36.
I have been very pleased with the results, much firmer sharper ride, sharper turn it, as i suppose you would expect. I have also noticed better braking, the tyres seemimg to bite into the road surface better. Does anyone know at what point the gains will stop and a negative result will happen? My car is an Stiv6 with Toyo 215/40/17 tyres.
Keith.

 

When they explode!

I would be worried about higher temperatures that may cause deformation in the tyre.

Follow the manufacturers guidelines or it could cost you big style.

 

The tyres probably "feel" better as they are stiffer, but you are also reducing the contact patch with the road so absolute grib will drop off at some point soon if you have not already sacrificed some. I would think the tyres are considered safe to inflate to 40-50 psi unless you get them very hot by doing a track day or something. At your higher pressures you will also be reducing the wear.

 

Remember that the pressure ups considerably when pushing on - I run mine at less than ideal cold temps to stop them cooking when used hard.

Richard

 

Keith, these pressures are fine for pressing-on but high for normal use. On a track day you'd probably go a bit higher still (mainly to reduce tyre-wall flex).

You're reducing the contact patch which is okay in the dry (contact patch and grip is a very complex issue, grip and load is easier to get your head around) but in the wet you're compromising the tyre's ability to clear water, hence grip.

Overall, you'll probably be better off going lower. Anecdotal evidence on here suggests you might get better wear with higher pressures, but that ain't the question.

Whatever you do, don't ask Simon de Banke for his view. Life's too short

Cheers,

Richard.

ps Hi Si!