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Ideal tire pressure for some 245/40/18's?

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Old Dec 2, 2007, 01:59 AM
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Ideal tire pressure for some 245/40/18's?

I am currently running BFGoodrich g-force T/A KDW-2's and wanted to know what the ideal/correct tire pressure was for these tires? I have been noticing my gas mileage has been suffering since I last had my wheels/tires mounted+balanced and am thinking the shop over-inflated them, anyone have suggestions for tire pressure?

Thanks
Old Dec 2, 2007, 10:06 AM
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Have you tried stock tire pressures?
Old Dec 2, 2007, 10:37 AM
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No, I haven't. I'll give it a try. Thanks!
Old Dec 2, 2007, 11:15 AM
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I just checked...It's 26psi all around and so I'll go ahead and fill it up to stock which is 32 in front and 29 in the rear...

Is that correct?
Old Dec 2, 2007, 06:44 PM
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Correct. FWIW...I run 35 front and 32 rear for street...I (now) will be switching it up to 32 / 36 for HPDE's.
Old Dec 2, 2007, 06:54 PM
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Yeah I just went ahead and did 32 front and around 31 for the rear, i'm going to see how it goes, but most prob I'll be added more.

Thanks for the help MRevo2006!!
Old Dec 2, 2007, 07:29 PM
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35f. 32r, to start, and adjust from there to your driving style.
Old Dec 2, 2007, 07:32 PM
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Danny23,

When you say adjust, what would raising and lower the pressure result in? How would it change the drive of the car?
Old Dec 2, 2007, 08:25 PM
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This is something I was talking to someone else about on a concurrent thread. All the text will tell you that if you want to decrease understeer, you would increase psi in the front tires--vice versa for the rear.

But from what I've experienced with motorcycles and after discussing it with others that actually track their cars; it seems that if you want the car to slide more in the front or rear that you would increase the tire pressure. If you want more grip, you decrease tire pressure.
Old Mar 4, 2008, 01:20 AM
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What would increasing the tire pressure do to gas mileage, ride quality, and performance? I'm sure that each of those 3 would be achieved on totally different settings, so if someone wouldn't mind helping me out with that, I'd really appreciate it!

I just had 2 new tires put on and after having that done, my car feels like it's loose, like it's a boat. I mean it's not drastic, but it's definitely noticeable. The only thing that has changed has been the addition of 2 new tires in the back.

Now I know changing just 2 tires is a no-no in a Evo, but my old tires were barely worn, they were down to 8/32nd's while they come new at 10/32nd's. The new tires are in the back and the old ones in the front.
Old Mar 4, 2008, 08:47 AM
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No takers ^^^
Old Mar 4, 2008, 12:15 PM
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Originally Posted by Inprogress
What would increasing the tire pressure do to gas mileage, ride quality, and performance? I'm sure that each of those 3 would be achieved on totally different settings, so if someone wouldn't mind helping me out with that, I'd really appreciate it!
Higher pressures within the acceptable range would yield greater gas mileage, a stiffer ride, decreased handling and premature center tire wear based on crowning of the tire.

I run 32/31 with your same size. Also, be sure to have your alignment checked at least 1x/yr. If you're interested in a smoothe ride and good gas mileage then dial in 0 toe and limited negative camber (if any).

Good luck.
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