Question for blacksheep tire pressures

[TA28]

hoosier 305 645 18 s80 or s100 what cold pressure did you start with on kohr cars.i know not air but nitrogen was used.
I know the radial tire really don't heat up like bias ply I used on my old boss 302 we use start 23 psi.
The radial 28 or higher depending on temp.
Chris

 

[blacksheep-1]

hoosier 305 645 18 s80 or s100 what cold pressure did you start with on kohr cars.i know not air but nitrogen was used.
I know the radial tire really don't heat up like bias ply I used on my old boss 302 we use start 23 psi.
The radial 28 or higher depending on temp.
Chris

Hard question to answer, I base all of my pressures off of hot pressures., I start around 20 psi cold and sort of work backwards when they are hot. For Hoosiers you are looking at 32 psi hot

**ALWAYS USE MFG RECOMENDATIONS FOR TIRE PRESSURE**

tire pressure mapping

I was asked on a FB page to explain how I do this so I'm sending them here. It's quite cumbersome to explain on FB. I have been fortunate enough to work with some very talented people over the years who have brought me along. They NEVER gave me the whole answer but expected me to figure it out...

trackmustangsonline.com

 

[TA28]

Ok here another coming off track how long does hot tire pressure stay before cooling off. Thanks chris

 

[Bill Pemberton]

Wow, interesting to know as I have never started that low cold ever, so something new to try thanks to Mr. Tire Guru of the Swamp!

 

[blacksheep-1]

Ok here another coming off track how long does hot tire pressure stay before cooling off. Thanks chris

They cool down right away, so you need to come in a lap early to avoid the traffic and grab them on pit row.

 

[blacksheep-1]

Wow, interesting to know as I have never started that low cold ever, so something new to try Mr. Tire Guru of the Swamp!

You would not believe some of the pressures I have sent cars out on, so low that I won't post them because I don't want anyone knocking the tires off the bead on the outlap

 

[TA28]

Bill I was shock at starting pressure. BUT remember black sheep uses nitrogen. Not compressed air .2 different rates of expansion.

 

[Bill Pemberton]

Good point, and we know I am cheap, so I will only use freeeeeee air, ha! I start cold around 26-27 lbs on my R7s, so I imagine BS1 will tell me, even with the free stuff, I could go a little lower?

 

[TA28]

I running 27 to 28 depending on air temp at track .lower when it gets warmer.
Coming off track and back in pits I check pressure. So I might be high if cooled off few degrees.
And yes I use compressed air. I'm running hossier s80 and s100 tires and continental slicks made by hoosier

 

[blacksheep-1]

Go buy some cheap air/water separators from Lowes or Home Depot, put them in line, and drain the compressor before you fill the tires.

 

[TA28]

Go buy some cheap air/water separators from Lowes or Home Depot, put them in line, and drain the compressor before you fill the tires.

Come on blacksheep that extra water in the rim gives bill added advantage . Acts like flywheel counter weight helps him go faster in straights.
LOL
sorry Bill couldn't resist.

 

[blacksheep-1]

Since tires routinely hit 200 degrees tread temp, you can see the difference.
Throw some water in there and it gets even crazier.