Correct tire pressure to run?

TexasSnake

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I recently put some Nitto Invos on my car and the max tire pressure states 51 psi. Obviously you don't inflate to max. Right now they are all set at 38 psi. Does that sound about right? I'm just wondering if this could be a contributing factor to the "loose feel" which I described in a recent thread.

My driving consists of street driving (no track) with an occasional "stomp someone" run when a somewhat worthy opponent is in sight. :)

I did a search and saw mixed reviews so some educated advice would be appreciated.

Thanks...
 

bluesrt

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38 sounds good,try 45 and see if the loose feel goes away
 

Steve 00RT/10

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I think whatever your door sticker says is what you're supposed to run at on the street. Probably 29# like the older cars. MPS also go to 51# max, but are supposed to be at 29 for non track stuff.


Steve
 

kwiksilver

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the correct tire pressure should be on the drivers door opening. I think it's about 30 pounds.:dunno:
 

Sweet Ride

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I run mine at 38 PSI for "fuel economy."

Less PSI will give you a softer tire which generally means more traction. It also contributes to faster tire wear.

More PSI will give you a harder tire which generally makes the car jounce over bumps and road irregularities. Too much PSI will also contribute to wheel hop and broken parts if you are trying to stomp a worthy opponent.

I have always run my tires above the recommended factory pressures for street driving.
 
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gb66gth

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Dude, you're waaay overinflated! At 45 or even 38 your tire is crowning and you're only riding on the center of the treadface. Fill them cold to 29psi, that should definitely solve the problem.
 

ulllose

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I also agree to the 29 psi, but on a side not i have had several High performance cars that recommend 29 psi on the tires and every car/tire i have had worn the centers worse and thats with the tires inflated to 29psi and i check them always!!!! So moral of the story would be that i think the tires really needs to be a few pounds less, like 26-27, anyone else agree?????
 

Steve 00RT/10

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I have run 29 pounds except for track stuff for almost 90,000 miles with completely even tread wear. I got 33,000 out of the first set of fronts and over 35,000 out of the 2nd set. They were MPS tires. .......no experience with any other vehicle running the same type of tire.
 

bluesrt

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I also agree to the 29 psi, but on a side not i have had several High performance cars that recommend 29 psi on the tires and every car/tire i have had worn the centers worse and thats with the tires inflated to 29psi and i check them always!!!! So moral of the story would be that i think the tires really needs to be a few pounds less, like 26-27, anyone else agree?????

yep, if the centers are wearing to quick,definatly over inflated
 

Kala

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I run 27 PSI in the front, and 29 PSI in the back.

I'm currently at 16k miles, and tires are still good.
I'll probably change them out next year, because of age not wear.
 

ulllose

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I run 27 PSI in the front, and 29 PSI in the back.

I'm currently at 16k miles, and tires are still good.
I'll probably change them out next year, because of age not wear.

Wow 16K and not worn.........good for you i replaced mine a 14K and the backs were smooth. I thought I did great with 14K miles
 

Steve 00RT/10

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I run 27 PSI in the front, and 29 PSI in the back.

I'm currently at 16k miles, and tires are still good.
I'll probably change them out next year, because of age not wear.

What is the purpose of running less than recommended in the front for street use?
Tires should be good for 6 years from the date code on the tire. That's the Michelin warranty window.

Wow 16K and not worn.........good for you i replaced mine a 14K and the backs were smooth. I thought I did great with 14K miles

When MPS were going cheap a few years back (as low as $138 ea), I stocked up on 4 sets of rears and burned a set off every summer for 5 years in a row....roughly 10K miles per pair. Sometimes less.:drive:..As they were all 01 produced overstock tires, I timed the last set to be done on the 6th year from the date code.

Steve
 

Kala

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What is the purpose of running less than recommended in the front for street use?
Tires should be good for 6 years from the date code on the tire. That's the Michelin warranty window.

To me, its just a handling/ride preference on the front PSI. My car seems to handle smoother. I live in a mountainous area, with very twisty roads in and out of our valley. I think the hard run flats, do better 2 LBS lower with the rough, twisty mountain roads I drive on.

As far as age, I'd prefer not to push the envelope. My first Gen I had tires that were 5 years old when I got it... Those things were very slippery, even though they had a lot of tread left.

Again its just preference I guess... :dunno:
 

Racer Robbie

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We run 34 Front and 30 rear with Michelin PS2 tires, this takes out some of the push or under steer that is dialed in at the factory stock setting of 28 psi.
 

Yellow32

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I recently put some Nitto Invos on my car and the max tire pressure states 51 psi. Obviously you don't inflate to max. Right now they are all set at 38 psi. Does that sound about right? I'm just wondering if this could be a contributing factor to the "loose feel" which I described in a recent thread.

My driving consists of street driving (no track) with an occasional "stomp someone" run when a somewhat worthy opponent is in sight. :)

I did a search and saw mixed reviews so some educated advice would be appreciated.

Thanks...

RULE OF THUMB, when using air (vs. nitrogen, etc) inflate to 65% of the max inflation (on any tire) for 'regular' driving conditions. The number on the driver's door is for 'fuel economy' and is not a safe pressure when the weather is cold much less cold and wet. Plus, the driver's door rating is only for the exact same make/model tire as the car came with originally.

inflate to 70-75% if will be driving in continuously wet conditions (pretty much you would only do this if you were running at the track as the tires will never full heat up in the rain).

Do the same with pretty much any passenger or truck tire and you'll be good. For instance, on my crew cab's tires, they are max inflation at 82 pounds so I keep them at 54 pounds (cold pressure).

A "fully heated" tire should be no more than 80% of the max inflation (to keep performance and saftey in good standing).

The only reason to run tires under 60% of max if you will be going to the drag strip and then only on the rear tires (as you will be heating them more than regular or track driving will, burn outs and all).

-J
 
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