I went from 38.5 to 35.5 all around and it feels a lot better. Am i wrong?

 

No.

 

I run what the factory says, 36 Front and rear.

 

Also, just curious, what's with the half-pound inflation pressures?

 

I just have a gut feeling it changes half pound in different weather conditions.

 

Changes a hell of a lot more than .5 pounds.

Cheers, Josh

 

lol. juuuuust a bit more.

 

I treat my car more like an aircraft than a car because 'Spirited' driving that results in a crash has about the same effect. Tires are the only direct link to the road so deserve some respect. Always heard/read that the manufactures rating is the one to go by, not tire sidewall ratings. So OK, the question. Do tire manufacturers follow some secret code that balances all tire constuction vaiables to a base sum that the car makers then use? Just seems a little strange that 15" 205 50's should run the same pressure as 15" 245 45's. Or should the tire ratings be used when going radical, like 18" 295 30's?

 

i need to quote you. I'm putting some of that in my sig.

 

I never said i knew what I was talking about so how much can the pressure deviate? without getting a puncture.

 

10 to 15 pounds, perhaps more. It takes very little time top get the air pressure to rise. Porsche recommends 36 psi. That was based on the stock wheel and tire sizes on a 951. Tires have improved significantly, through the years, so some of that methodology is inaccurate. Folks are using lots of variations around 30 to 40 psi.

 

I must be one of the only ones who uses tire temps for setting pressure on the street as well as the track

 

So for those 17" tires, like F 225/45/17 and R 245/40/17, how much pressure is used? 32 lbs all round?

 

Not exactly sure what you mean by that (could be the sleep deprivation), so I'll come back to that later...but the inflation pressures printed on the sidewall are the maximum pressures the tires can safely handle, not the best pressures to use.

 

What I mean is the tread span on narrow or wide [and short or tall aspect] - fixed variable, and Air pressure - adjustible variable, has a big effect when multiplied by centrifgal force. So, would you want less air pressure in a wide tire to keep the tread flat on the ground?, or more pressure to stablize the sidewall?, or what I pray is true - that the tire manufactures have taken all this into account and built the tires to a standard which the car manufactures then apply their weight, velocity, and cornering G force numbers too and give us ONE PSI number for ALL occasions. I have never heard a definitive anwser to this, probably due to litigation concerns, but I'm more worried about my a$$ before the fact then theirs after the fact.