The Alien

Hi guys, I'm a bit confused about tire pressure:

I have a Mustang GT 05 convertible, When I bought it preowned, they gave me the tires at 43psi when it should be 32 (17" wheels).

I thought at first that it was me to be confused with the new scale (I'm coming from Europe and we use bar instead of psi) but making the conversion I realized that they were too inflated and I fixed them

After that, I left the car on a Ford dealer for a check and again, they inflated the tires at 42 psi...

Now, I received the new tires from American Muscle, 19" and the pressure was 43...

I don't understand if I'm missing something or there is the habit to overinflate for mystical reasons but now I see why there are bunches of exploded tires on all highways...

AzPete

Tire pressure has nothing to do with rim size. Simply read on the side of the tire side wall to see what maximum pressure under the maximum load is recommended by the tire manufacturer.

Tire pressure on the door opening of the car is what the car manufacturer recommends for best ride. Not always best for wear and may or may not match the current tire on the car.

I use the following method for the average pressure for my vehicles.

I air the tire to the sidewall marked pressure and drive the car thru a bit of water and look at the track left.
Then gradually lower the pressure until I get a solid footprint of the tires full tread width.
To low and the center area will show less print, to high and the outer edges will be a weak print.

I have also used a chalk mark across the tire but the method involves more driving. My way can be done in your garage.

The Alien

Yep it doesn't have nothing to do with sizes, it can change a little bit with the tire ratio because it can change the weight load distribution but it's always minor changes.

The maximum pressure on the sidewall is shouldn't be the recommended I think but it should be the pressure we should never reach to avoid a tire damage or explosion (usually for Pirellis are 52 psi)

43 psi it was way too much (also because the tires that were used when I bought the car) were bad worn and more on the middle than on the side, due to excessive pressure.

what it was confusing me that the dealer, Ford and AM used by "coincidence" the same air pressure and I was wondering if there was a special reason or "muscle car tradition" that I don't know

43 psi are 3.0 bar, it's a motorcycle tire pressure

PS: I like your grille with ghost foglights

AMDanBailer

We set the tire pressure a little high when shipping out wheels. We do this so that if your wheels loose a little pressure in transit to you, with the weather changes etc.. you won't have to add anything when the wheels get to you.

We recommend checking your PSI when our wheels arrive and adjusting the PSI to the recommend setting. I've always set my PSI between 32-37, that will be good for your car as well!

I hope this helps.

-Dan

The Alien

Thank you Dan, please don't misunderstand my post, it wasn't a complaint but it was a coincidence that in all three cases someone else inflated the tires there were all three the same.
I supposed that I was wrong because I was coming from the old Continent and maybe here there were different ways (but I'm pretty much sure that the air is the same unless in Tibet )

thank you again for the info

AMDanBailer

No worries! I'm glad to hear you're all squared away now. That's definitely an odd coincidence!

Hit me up if you ever have any questions, need some assistance or just want to chat!

-Dan