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I went to Murcott Driver's Training Lvl 2 last Monday. Put 38psi on my tyre all around (they recommend min 36psi on the day).

One of the instructor, Pete, told me during Lvl 1 course in January that there's nothing wrong putting 40psi all around, he always had that pressure on his car.

Manufacturers recommend lower tyre pressure like 32 or 34 is for comfort level, so they don't have to spend millions on designing limo smooth shocks on mass production cars, and easier to sell their cars coz when ppl test drive they feel the comfort ride, not a bone-jarring ride.

If you went any track day course, they would recommend min 40psi (cold tyre pressure) for performance and safety.

I think 40 psi is not too high, you'll get better fuel economy, longer tyre life, and don't believe if someone told you about the crowning effect, that only start to happens if you put too much pressure like 50 or 60psi and your tyre is extremely bad quality ones. The reason why I don't put 40psi is because I have to drive over tram tracks everyday, and with min 36-38 psi all around, the comfort level is acceptable.

I know lots of guys here are into drags, and some will think that anything above 30psi is already on the wrong side of the pressure scale. For drags you want lower tyre pressure to get that sidewall flex for better grip under extreme hard acceleration, but that will wear out your tyre quickly on everyday's use.

So unless you own a tyre shop or a best friend of them, pump up those tyres... I hardly noticed any difference in ride when I used to have 32psi and now 38psi.

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Originally posted by rs73

Manufacturers recommend lower tyre pressure like 32 or 34 is for comfort level, so they don't have to spend millions on designing limo smooth shocks on mass production cars, and easier to sell their cars coz when ppl test drive they feel the comfort ride, not a bone-jarring ride.

I got told this on an AAMI defensive course a few years ago.

I run my 18s at 40psi front and 38psi rear. I think my stockies (16s) were on about 35psi but they have been in my shed for a while! :P

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