what tire pressure to go by??

[Quattro Pete]

Originally Posted By: stockrex
Low psi cause excess heat and low mpg

And too high of a PSI provides for a bone jarring ride and a case can also be made that it puts additional stress on suspension. Gotta find a balance there somewhere. Most car manufacturers typically know where that balance is, but of course small adjustments can always be made to fit personal preferences.

 

[johnsmellsalot]

If your vehicle has the correct tire size, go by the recommended pressure on the sticker. Check the tires when they are COLD. Cold tire pressure is when the vehicle has NOT been driven.

If the tires are NOT the correct size, add a pound or two to the recommended pressure. \

Everything about your vehicle is designed around a certain pressure. Even your suspension is designed to work best with a certain pressure.

Incorrect tire pressures can have negative effects on tire life, handling, and ride comfort.

 

[sciphi]

As long as it's at least 30 PSI for a road-going car tire, it's okay in my book. I personally run 40+ PSI in tires rated for 51 PSI cold, and still have more edge wear than center wear.

 

[teddyboy]

The Volvo has a door placard recommendation of 35 psi. Go much above that and the ride is really rough. The two Toyotas each have a recommendation of 30 psi. I routinely run 32-34 psi on both of them. So I guess my answer is, it depends first of all on the car and its recommended psi. It would also seem a good idea to account for the car and how it's driven.

 

[CharBaby]

I like equal or ~2 lbs more PSI in the front tires and equal to or 1 lb less in the rears(compared to the place card) for normal driving around town. I adjust accordingly when traveling on vacations with luggage and people. And even then, I only add the extra PSI in the rear tires depending on the extra load.

 

[CapriRacer]

Originally Posted By: Rand
is this similar to your load tables capriracer?

http://toyotires.com/tires-101/load-and-inflation-tables


Yes, those are the tables - BUT I would suggest you read this to help fill in the gaps:

http://www.barrystiretech.com/loadtables.html

And one last word: Care should be taken when using these tables. Do NOT use the tables directly!! The loads listed for the pressures are MAXIMUMS!!

Over the years, the vehicle manufacturers have learned that they need to provide much more load carrying capacity in their tire specifications - meaning the placard size and pressure.

 

[jorton]

My cars label specified 32 but I think these soft compound tires would have worn longer @ 36 or 37. I don't know for sure how hard compound is in new tires so I will suggest car label psi +15%.

 

[stockrex]

Originally Posted By: jorton
My cars label specified 32 but I think these soft compound tires would have worn longer @ 36 or 37. I don't know for sure how hard compound is in new tires so I will suggest car label psi +15%.


I agree, the psi on the door is just too soft my taste, 32 psi for 4 door, which gets driven at 70mph nearly straight line.

going a few lbs over the door sticker upto the max rating of the tire should be fine.

 

[ahoier]

The door placard is aimed towards "comfort" - not for "performance" - I typically "meet in the middle" somewhere between the door placard (35 psi) and the MAX COLD PSI listed on the tire (40 osi)...usually set to 38 and leave it at that.......always check them in the morning, before the car has been driven...

 

[Volvohead]

Originally Posted By: 440Magnum
GO BY THE STICKER ON THE CAR.


NOT ALWAYS.

As always, the vehicle placard is the starting point, and is a safe compromise in most circumstances. It is almost always the absolute minimum inflation that should be observed. But common sense and experience with the specific vehicle sometimes allow reasonable deviation, usually upward.

Case in point: our S60R. The placard inflation is too low for some tire sidewall designs in the optional wheel size. There were reports of premature tire sidewall failures on several enthusiast boards about it. Many R owners in the know who run the optional wheel package run inflation pressures significantly higher than the placard recommendation to avoid those problems.

Obviously, never exceed the tire manufacturer's rated maximum inflation.

As we all know, neither vehicle or tire manufacturers are always right about what's always best.

 

[HTSS_TR]

Originally Posted By: Volvohead
Originally Posted By: 440Magnum
GO BY THE STICKER ON THE CAR.


NOT ALWAYS.

As always, the vehicle placard is the starting point, and is a safe compromise in most circumstances. It is almost always the absolute minimum inflation that should be observed. But common sense and experience with the specific vehicle sometimes allow reasonable deviation, usually upward.

Case in point: our S60R. The placard inflation is too low for some tire sidewall designs in the optional wheel size. There were reports of premature tire sidewall failures on several enthusiast boards about it. Many R owners in the know who run the optional wheel package run inflation pressures significantly higher than the placard recommendation to avoid those problems.

Obviously, never exceed the tire manufacturer's rated maximum inflation.

As we all know, neither vehicle or tire manufacturers are always right about what's always best.

I agree.

But some S2000 drivers who track their cars found that the optimal pressure is 2-4 PSI above placard for the front and 2-3 PSI below for the rear for OEM size. For +0 up-size, from 215/45-17 Front 245/40-17 Rear to 225/45-17 Front and 255/40-17 Rear, the optimal pressure is up 1-2 PSI for the front and down 3-4 PSI for the rear.