What are you guys running for air pressure in your stock goodyear supercar tires. Spirited city and country road driving.

 

I don't run the stock tires, but I run 30-31psi!

 

32-34 for regular street driving

 

32/32 psi

 

I run stock ruber at 30/30 and have PERFECT tire wear

 

I've noticed several posts with two dirrerent numbers so I assume these and front/rear respectively. I'm curious as to why you would want to run more pressure in the rear than in the front.

 

Goodyear EMT sticker says 30 psi cold, add 4 psi if tires are hot. Mine are running 33 hot.

 

Thank You..

 

30 lbs front and rear

 

 

The post was an inquiry for advice as to how much air to run in F1 Supercar tires for spirited driving - not anything about what the manual says or what's best for tire wear. Varying the tire pressure can have a dramatic affect on how the car handles (good or bad). I think the values posted on the door are "dumbed down" based on many things (comfort for one) and are a "one size fits all".

I didn't post an answer because I didn't have a definitive one and I'm not an expert but since nobody else did - I'll start the ball rolling and maybe some track guys will jump in (although you could probably search on this and find a lot more). For spirited driving, I'd definitely bump the front up to 35 and I leave the rears at 30 although one post I by a track guy recommended 35/28 for the kind of driving you're speaking of.

 

I'm a go-by-the-book kinda guy. that's why I quoted the sticker pressures. Figure the engineers know more about their product than I do.

 

That's your choice but I'm pretty sure that's not the viewpoint of the original poseter who was asking or he could just read it out of the book just like you did. I know all of the engineers are smarter than I am - there is no question there. The thing you have to remember is that they have to compromise everything they do to fit the masses.

Here's one of many examples - the air box on your car is very restrictive. Is it restrive because the engineers are not smart enough to make a better one or is it because they were required by the government to meet sound restrictions? I think you know the answer to that. If you don't, maybe you could find and ask one of them who are not only are engineers by day but enthusiasts (spirited drivers by night/weekend) and I'll guarantee you that they aren't running the stock air box nor air pressures for that matter.

 

That's true, but only to a point. The figure given in the manual or on the door frame is intended for normal street use. It's a balance of comfort, tire wear and gas mileage. It's not intended to maximize performance.

The only way to really find out what tire pressure you car will function best at for "spirited driving", which I read as road racing or track events, is to experiment. And the only way to really be sure is to write down the tire pressures of all 4 wheels cold, and then measure them again hot. Also, if you have an infra-red thermometer, take the temps of each tire tread immediately after stopping -- outside edge, center, inside edge. Chart those against performance/handling. Usually, if the car is understeering, you either need to go up a bit with the rear pressure, or down a bit with the fronts. That will depend on how the tire temps are and whether the tires are rolling onto the shoulders. If you're oversteering, it's the opposite -- up with the fronts or down with the rears. Tire pressure will vary with outside temperature, track surface temps, sunny day, cloudy day, etc. Keeping a record of the tire pressures against those conditions can give you a starting point for whatever you run into at the track so you can adjust your set-up.

And if you don't want to get that technical about it, start at 30/30, drive the car, see how it handles, and adjust accordingly -- more rear pressure for understeer, more front pressure for oversteer or less front pressure for understeer, less rear pressure for oversteer. Again, it depends on tire roll and grip.

YMMV.

 

vette 30/30 with even tread wear.
matrix&audi 34/34

 

I drive my car daily...hard
I hit 3 digits at least once daily (in town)
for comp driving I would add a little to the front but i stick good at 30/30 AND I have very good even tire wear as a bonus.
Lighten up

 

I forgot to add that I have a habit checking pressure in the morning on cold tires in the garage.

 

I think any tire manufacturer would tell you that those pressures assume normal driving and that you should add pressure for high speed driving. I've had cars that have stated this in the owners manual although none probably do now due to that being "politically incorrect". Triple digits is not normal driving. I stand by my original post.

 

I agree. I run mine on the high side ... improves cornering performance.

 

Gosh, thanks for the input guys. Looking back through the posts, it still appears that most people run their pressure within the stated range of 30 - 34 psi. I was simply stating what I have in mine and what the sticker recommends. You provided a lot of useful information. Thanks again. See, I'm smiling >>>>