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Mike V 06-06-2015 09:39 PM

Tubeless tire pressure
 
1 Attachment(s)
I recently changed to tubeless slicks,Hoosier 29 x 9 (bias ply).The car is an automatic weighing 3300 pounds.I am still running 12.75 pounds of air.But after looking at this picture I think I need to raise the pressure.Any suggestions of where the pressure should be?

J.R. Haddad 06-06-2015 11:19 PM

Re: Tubeless tire pressure
 
What size is the rim? J.R.

Myron Piatek 06-06-2015 11:39 PM

Re: Tubeless tire pressure
 
I've heard pressures from 14 to 25+ lbs from 9" tire racers. Lot's of variables, but most seem to be in the high teen to low 20 range. I have Hoosier 9"X 30" Lightweight Radial Slicks at 21 lbs on a 10" rim, car weighing 3,540 and footbraking. Wider rims allow more pressure and radials seem to like a little more than bias ply. I fine-tuned it by watching if contact is being made all the way across the tread (may need less if not) or if rubber is being laid over the side (may need more).

Mike V 06-07-2015 07:52 PM

Re: Tubeless tire pressure
 
They are 15 x 10 rims. The car is working great ,but I'm concerned about how safe it is.Thinking of going up 1/2 to 3/4 of a pound and see what happens.

John Dinkel 06-07-2015 07:59 PM

Re: Tubeless tire pressure
 
Try 20 PSI. Don't be afraid of more pressure in the radials.

Sean Marconette 06-07-2015 08:20 PM

Re: Tubeless tire pressure
 
I run 15x10 with 29.5x9 bias ply but a stick car. Never been above 15 lbs unless I want to spin. OP stated bias ply. Try 13 lbs and work up from there.

Sean

J.R. Haddad 06-07-2015 09:16 PM

Re: Tubeless tire pressure
 
Bias ply and radials have nothing in common. Start at 20 lbs. with a 10
inch rim, and go UP from there.

GTX JOHN 06-07-2015 10:36 PM

Re: Tubeless tire pressure
 
Same tire and wheel size on one of our bracket cars = 16 to 17 is where we
ended up. Seemed high for bias but lower pressure really tore up sidewall.
Our car is 3300 LB. with 1.5 to 60 Ft.

NOVALOU 06-07-2015 10:50 PM

Re: Tubeless tire pressure
 
Quote:

Originally Posted by Mike V (Post 472918)
I recently changed to tubeless slicks,Hoosier 29 x 9 (bias ply).The car is an automatic weighing 3300 pounds.I am still running 12.75 pounds of air.But after looking at this picture I think I need to raise the pressure.Any suggestions of where the pressure should be?


What does the car usually 60' like? Definitely more pressure, the tire looks like it's trying to roll over itself.


I would up the pressure a bit, work towards 13-14lbs., and maybe make a shock adjustment if needed also.


I'm no expert though.

Mike V 06-07-2015 11:34 PM

Re: Tubeless tire pressure
 
Quote:

Originally Posted by NOVALOU (Post 473084)
What does the car usually 60' like? Definitely more pressure, the tire looks like it's trying to roll over itself.


I would up the pressure a bit, work towards 13-14lbs., and maybe make a shock adjustment if needed also.


I'm no expert though.

Usually low to mid 1.60's. I will have to up the pressure and mess with the rear shocks.I see a day of testing in my future. Thanks


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