Tire Inflation-Discussion Thread

I thought this would be an interesting discussion thread of a technical nature.
Tire Inflation Values
When you go to the various Tire Manufactures sites you see they recommend that you consult the piller tag and the Car Manufactures recommended tire inflation values.
And oh boy lets not forget the old tire on the glass pictures to show how the tread is contacting the surface.
Dont know about you but I got no setup to see under my tire like that.
But how can this piller tag value be correct for any tire other than OEM tire supplied?
Especially in the performance tire market there are so many differences between tires and designs I cannot accept that the pressure posted can be correct across the board.
Size, Design, Ratings, ect, ect, ect...
All these can make a difference.

So what else do we do to find the correct pressure?
The discussion is open now.
Lets hear it!!!!

Silence?
whoooo...

ixtlan said:

Silence?
whoooo...

Click to expand...

where's MrClean when you need him...

he'll have the goods, trust me. be patient or PM him...

One way I have adjusted tire pressure value is by doing a burn out, then measuring the foot print. Once I obtain max print in width I'm there. As far as front tires go I follow the recommened press stamped on the tire. Have tried various other methods and have found this to work best. Also use the tire press stamped value method on my 18 wheeler. Have found this actually achieves max mileage in tire wear as well as increased fuel mileage. Downside is ride quality is slightly degraded. JMO and Exp.

I follow the 10% below max psi method. Its served me well for about a month now and I defiantly saw an increase in mpg.

I found a very interesting article on this from a Diesel Truck site.
It also has very good test to check your pressure based on your load.
It is called a Chalk Line test.
It seems to be a logical test to find the proper tread contact pattern.
Gonna give it a try and see what I come up with.

http://www.thedieselstop.com/contents/getitems.php3?Proper Tire Inflation

Well that was an interesting little experiment.
I did the Chalk Line test and was actually amazed how well that worked.
I started at 42psi and rolled it down the block (takes about 100ft to get a good read).
It showed the tires F&R overinflated.
So I swapped direction of the car to go back down the block and remarked the tires. Lowered to 40psi and rolled again.
Chalk pattern (Where it wiped off) got wider towards the edges.
So did it again this time at 38psi.
Spot On!!!

So peeps get that chalk from the kids and get rollin!!!!

38psi All the way around for me.

Anyone else try this yet?
Chalk Test?
I have had a few people try it and they were actually amazed how well it worked.

What tires are you running? P-Zeros, 235-55/17, aka stock tires w/ non-Bullitt GT optional wheels?

Bingo said:

What tires are you running? P-Zeros, 235-55/17, aka stock tires w/ non-Bullitt GT optional wheels?

Click to expand...

Stock wheels.
Michelin Pilot A/S Plus 255/45/17 all the way round.