[Motormasher]

Can anybody help me with some tire info? I got some "new" American Racers from a couple of years ago but I'm not sure what the compounds are. I have several new SD-23B's and a couple of SD-28.

I know back in the day there used to be a sythetic rubber but don't remember how to identify it. Does anybody else still run these tires anywhere?

I would sell a few of these if anybody wants one to run Paragon next week.

[slide22]

23 and 28 are pretty soft. I had a chart somewhere that compared compounds between Hoosiers and American Racers. A SD-23 was like the equivalent of a D10 Hoosier, and and a SD-33 is the equivalent of a D12.

[tqracer65]

If they are anything like the tq american racers teh sd23 is a pretty soft tire

[Tim Clauson]

SOFTER- SD-23, SD-28, SD-33, SD-35, SD-38, SD-44, SD-48, MD-50, MD-53, MD-56, MD-57, HD-65, HD-70- HARDER

Tim Clauson

PM me - we ran AR for the 2004 and 2005 season, I have some notes if interested

[TQ97]

If the same as TQ's, the 23 "B" is as soft as a 23, but wears like a 28.

[c47]

tim,
does the sidewall stiffness increase as the tires get progressively harder or do the sidewalls stay basically the same but the tread compound gets harder?

[Tim Clauson]

Originally Posted by c47 tim, does the sidewall stiffness increase as the tires get progressively harder or do the sidewalls stay basically the same but the tread compound gets harder?

Back in the day we ran between a 23 and a 38 and then jumped to the MC2

Between the 23-38 there was small but not a huge noticeable difference between the sidewall "flex" There was as much spring rate change tire to tire as there was compound to compound. The big difference was when you got to the MC2.

The way I rated my tire spring rate was a bit primitive to be honest but it was nothing I was concerned with when changing compounds.

Hope that made sense ..

Tim Clauson

[jjsprt92]

The 23B's are a soft tire the B stands for Belted and were for more for a wing car,If I remember right the sidewalls in the Belted tires are stiffer,I bought several of these years ago a Daytons auction when I ran wing cars at Knoxville

[TQ29m]

AJ, wonder if we were sold a bill of goods? I was told the same story,the B, worked like a regular SD, cold, but when hot, didn't wear like that number. I have one, ready to recycle, I'll ck to see what is under the rubber. Bob

[Motormasher]

Originally Posted by jjsprt92 The 23B's are a soft tire the B stands for Belted and were for more for a wing car,If I remember right the sidewalls in the Belted tires are stiffer,I bought several of these years ago a Daytons auction when I ran wing cars at Knoxville

Thank you, I didn't know what the "B" was for, that is a big help.

Thanks to all of you for your help, I really apreciate it. I really like the AR tires expecially at Paragon.