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Discussion Starter #1 (Edited)
Let me pick your brains for a moment...

I come from the 4x4 world. I've spent the last 10 years involved in all aspects of trucks, Jeeps, and SUVs and did some offroading, etc. What we learned in the 4x4 world crosses over to the car world in some ways.

For example, lowering the air pressure in your tires increases traction. But... it also creates rolling resistance on pavement. Rolling resistance robs a little engine power and drops MPGs and creates heat.

Now, what I'm wondering is this: Assuming you have a mostly stock street car with bolt on mods like I do and you go to a track to run the 1/4 mile, would it be best to air down or air up? I'm only a little over 300 HP at the crank and I'm on all-season tires so I'm not going to spin all the way down the track, you know? So I don't need to air down, right?

In theory, if you leave your air pressure high, you'll reduce rolling resistance, free up horsepower and speed, and might possibly pick up a tenth in the 1/4.

Has anybody played around with this to see? Or am I just dreaming?
 

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Can't go too low on the Goodyear F1s in the rear or you'll loose the center footprint and your 60' times will suck. I run my fronts to 42 and ran my F1s at 24 - 26 when I ran stock rears. DRs 22 - 24.
 
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I would assume for you, stock door placard tire pressures.
 

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Discussion Starter #4
Yeah I think I'll try it both ways maybe and see what happens.
 

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also, if your pressure is too low - it will trigger the TPMS warning(s).
 

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Can't go too low on the Goodyear F1s in the rear or you'll loose the center footprint and your 60' times will suck. I run my fronts to 42 and ran my F1s at 24 - 26 when I ran stock rears. DRs 22 - 24.
Did you run that on the street too? I usually do 32 in the rear and 36 in the front, but i don't drag race either. Strip opens pretty soon though!
 

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If you can't break'em loose on launch, I would go with air-up. If most of your power is on the top-end, I think that is also a good reason to go with air-up.

If it isn't hooking-up well on launch, you have no choice but to explore some degree of air-down, to optimize contact patch at the sacrifice of some rolling resistance over the long run.
 

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Since you are talking about tire pressure. And please I don't mean to jake your thread OP. But I have been wanting to ask for awhile. I run 32 psi all the way around with F1's. When I have done a burn out which has only been three times. I only leave black marks on the sides with no black marks in the middle. So the tire is not leaving a black mark all the way across. Is there something I am doing wrong ? Again sorry OP I don't mean to jake your thread !
 

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Since you are talking about tire pressure. And please I don't mean to jake your thread OP. But I have been wanting to ask for awhile. I run 32 psi all the way around with F1's. When I have done a burn out which has only been three times. I only leave black marks on the sides with no black marks in the middle. So the tire is not leaving a black mark all the way across. Is there something I am doing wrong ? Again sorry OP I don't mean to jake your thread !
Bump you inflation pressure up a bit - the center tread will bow inward with low inflation (as you've noticed with your burn out pattern), whereas over-inflation will cause the center to bulge out more and less tread at the shoulders.
 

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So what pressure do you normally run at? I have 2012 Srt with f1s and run 40psi and I noticed today the tread is completely gone around the center on the backs at 7500 miles :/ the sides have a little more beef.
 

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my car say's the correct pressures for my 245/45/20 F1's is 32 all around.
 

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So what pressure do you normally run at? I have 2012 Srt with f1s and run 40psi and I noticed today the tread is completely gone around the center on the backs at 7500 miles :/ the sides have a little more beef.
I have a 2012 SRT8 with the staggered 255 rr/ 245 fr and ran them at 36-38 lbs. Not being able to rotate the wheels, my F1's lasted 27,000 (RR)- 28,000 (FR) miles. They had very even wear when I replaced them and still had maybe 2,000 miles left in them. Currently I run Hankook V12's 255 FR and 275 RR and have no odd wear patterns on these either. I track the car pretty often as well.
 

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Did you run that on the street too? I usually do 32 in the rear and 36 in the front, but i don't drag race either. Strip opens pretty soon though!
strip only. street 32 rear and 34 fronts.
 

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That's the correct tire pressure for normal driving, but not for drag racing at the track.
yea, I get that.. I was just pretty much addressing the 40psi and worn out in the middle guy below.

So what pressure do you normally run at? I have 2012 Srt with f1s and run 40psi and I noticed today the tread is completely gone around the center on the backs at 7500 miles :/ the sides have a little more beef.
 
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