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Author Topic:   UMP Tires
driver27
Dirt Full Roller

Total posts: 40
posted March 18, 2002 12:12 PM
Our track recently adopted UMP modified rules (lucky us...) and we are now going to run either the A-40 or the D-40. Can anyone give me some info on these tires such as durometer, grip, life, etc. Out track gets very hard and has some sand in it so it wears tires pretty quick. WE had been running the hoosier RC6 tire. Any info on how tire pressures compare to the RC6 would be greatly appreciated.

Thanks A ton guys.

Van

HEAVY DUTY
Dirt Roller

Total posts: 16
posted March 18, 2002 09:11 PM
I BELEIVE THE RC6 IS THE SAME AS THE H-40,WHICH IS THE HARDEST UMP TIRE.THEY DUROMETER AT 72 NEW,THE A-40 IS ABOUT A 62,AND IS BAD TO GLAZE.THE D-40 IS A 52 AND WEARS VERY QUICKLY ON AN ABRASIVE TRACK.IF YOU WERE WEARING AN RC6 OUT YOU BETTER STAY WITH A H-40,SAME TIRE JUST COSTS MORE BECAUSE OF THE POINTS MONEY.

driver27
Dirt Full Roller

Total posts: 40
posted March 19, 2002 07:52 AM
quote:
Originally posted by HEAVY DUTY:
I BELEIVE THE RC6 IS THE SAME AS THE H-40,WHICH IS THE HARDEST UMP TIRE.THEY DUROMETER AT 72 NEW,THE A-40 IS ABOUT A 62,AND IS BAD TO GLAZE.THE D-40 IS A 52 AND WEARS VERY QUICKLY ON AN ABRASIVE TRACK.IF YOU WERE WEARING AN RC6 OUT YOU BETTER STAY WITH A H-40,SAME TIRE JUST COSTS MORE BECAUSE OF THE POINTS MONEY.

Hey Heavy Duty, thanks for the info. I have your chassis numbered 002, its the one that has had a pretty glorious past, but still not working exactly right for me. Driver error is the most likely cause of the problems...

The track im talking about is I-20 speedway in SC. We race for the first time this weekend, so I will likely be calling you next week. In our tracks ultimate wisdom, i Think they are leaning towards the D-40, which will be a big mistake.

Oh well, thanks for the Info.

Van Keisler

HEAVY DUTY
Dirt Roller

Total posts: 16
posted March 19, 2002 10:39 PM
HI,VAN.THE D-40 TIRES WONT LAST LONG ON THE RED CAROLINA DIRT.IT IS TOO GRITTY AND ABRASIVE.THE A-40 IS GOOD IF IT DOESNT BLISTER.IF YOU RUN THE D-40 TIRES,RUN THEM ON THE FRONT A FEW WEEKS BEFORE PUTTING ON REAR,IT WILL MAKE THEM LAST BETTER.

driver27
Dirt Full Roller

Total posts: 40
posted March 20, 2002 08:05 AM
Thanks for the info Heavy, hopefully armed with some knowledge, I can talk some sense into the track people. Your right on the money about our clay, grit in the clay sands a tire down before it really gets hot enough to blister. Talk to you later.

Van

KMUDD
Dirt Roller

Total posts: 15
posted March 21, 2002 11:57 PM
hey heavy duty. While were on the subject I'm just learning about these Hoosiers. I've been running IMCA tires. I'm hoping you can give me some info on the difference between the A-40's & H-40's. I was told the H's don't have silicon and the A's do and that's why they glaze. Is this true? Also, what's a good way to get the glaze off, if any?

HEAVY DUTY
Dirt Roller

Total posts: 16
posted March 22, 2002 11:50 PM
THE A-40 TIRES CHANGED LAST YEAR AND ARENT NEAR AS BAD TO GLAZE AS THEY ONCE WERE.THE OLD A-40 COMPOUND WAS ACTUALLY THE OLD D40 LATE MODEL COMPOUND,NOW THEY ARE USING THE LM35 COMPOUND,AND YOU CAN SIPE THEM IN UMP TO HELP HEAT THEM UP QUICKER.THE H-40 IS ACTUALLY HOOSIERS D60 COMPOUND,WHICH IS A HARD DIRT COMPOUND.THEY WONT GLAZE,AND IF YOU CAN GET THEM HOT ENOUGH,THEY WILL GET HOOKED UP BETTER THAN A D40.THE PROBLEM WE HAVE HAD IS THAT IF YOU DONT START OUT LOOSE,WHEN THE H40 GETS HEAT IT WILL STICK THE RR SO HARD YOU CANT TURN THE CAR.

KMUDD
Dirt Roller

Total posts: 15
posted March 24, 2002 05:47 PM
THANKS FOR THE EXCELLENT ADVISE HEAVY DUTY!

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