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Discussion Starter #1
I have read a few forums regarding tire air pressures but the all are running the 17" rims (22 psi all around). Would it be roughly the same for the 15" wheels or a little more because of the taller sidewalks? I'm running a big block 460 with eibach springs, IRS, front tires 235/60/15 and rear 295/50/15. I will not be using on the track, only street.
 

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Junior Charter Member
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Is there a reason not to run what is says on the side of the tire? 22 is quite low for any size tire.
Because of the light weight. The number on the side of the tire is maximum pressure, not recommended pressure.
 

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FFCobra Craftsman
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The rule of thumb is one lb pressure for each 100 lb of car weight. But we have much wider tires than a typical 2400-2500 car would so can get away w/ less pressure even than the rule of thumb.
 

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Same pressure on all fours or do you carry a few pounds more in the fronts to offset the extra weight of the engine? I think ERA recommends 28 lbs. front and 26 lbs. in the rear.
 

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Pro FFR Builder and Moderator
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FFR's tend to be 50/50 to 48/52 weight distribution. Same pressure on all 4 work well.
Pressures are recommended on the weight of the car not the tires max. My wifes Fusion manufacturer recommends 34 all the way around even though the tires max is 44. Car weighs 3400lbs with almost 50/50 distribution. Running high pressures in a 2300lb car will give really pure ride qualities and really bad tire wear.
 

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I ran 26 psi front and 24 psi rear for 2 seasons (only 4k miles and some track time), and I had more wear in the middle of the tires than the outsides. So, this says that that pressure was too high. I could also feel an improvement at Mid-Ohio when I lowered pressure to 22 in the rear. I'm staying low for now.
 

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May help with traction as well! My first drive was with 29lbs and I accelerated like I would my truck and it just lit the tires up...lol OOOPS :scared: Cold tires didn't help but I have already dropped pressure to 24/24! Will see how that works in a month or so when things warm up? It was reading this thread that brought light to tire pressure and wear pattern on tread! More great info from experienced members!!
 

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I found that the tires at the 28lb level works best for me. It give me a solid comfortable ride and good control.

Running 30lbs makes the car very harsh riding.

Tried a number of different settings and 28 works best for me.
 
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