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RA-1 tire question

Old 06-21-10, 05:42 PM
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RA-1 tire question

The Chumpcar series is opening up their entries to SCCA/NASA IT and Spec race cars on a "try before you buy" type of program. Since my IT POS-7 fits right in with this type of racing we are entering the 24 hour race at Hallett in late August with a cast of "STELLAR" BMW/Porsche drivers to man the wheel of my spinning triangle POS.

Have any of you guys and gals run an enduro with RA-1s as the tire choice? If so what kind of observations did you have on the performance of the tire as a whole? Did you have some degree of consistency? Did they just fall off drastically after X number of laps? Any comments would be helpful.
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Old 06-21-10, 10:57 PM
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I've heard that they don't "fall off" like the Hoosiers tend to do. But I have no personal experience with them. Sounds like fun though.





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Old 06-22-10, 11:47 AM
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we ran em in the 2007 25 hours of thunderhill race.

they do pretty well, you'll wear them out before they "go off" as basically you're doing 1 big heat cycle

i think we were getting 6-8 hours out of em, but you'll have to actually verify this on your car.

in 2009 we ran hankooks, the car was 3 seconds faster a lap, and we were still getting about 6 hours
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Old 06-22-10, 06:19 PM
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Thanks for the input! I'm having to rethink my tire strategy a bit for this.
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Old 06-23-10, 08:19 AM
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We ran RA-1's on an ITA RX7 for a 13-hour enduro. IIRC, we got 8-10 hours out of them with the fronts wearing out first. I think that we could have stretched the rears out more, but we were in for a pad change and had the fresh tires already there. This was a couple years ago.

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Old 06-23-10, 04:29 PM
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I found a place selling R888s for less than a 100 apiece. I hadn't planned on new tires for this event but it may be worth it to pick up at least 4 for back ups to my 8 scrubbed RA-1s. Decisions, decisions!
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Old 06-24-10, 11:37 AM
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we did the math when we were putting the car together in 08

1 season of IDRC/battle of the imports whatever it is racing = under 15 minutes. they rebuild the engine at least once.

1 season of NASA Honda challenge = about 22 hours

1 25 hours of thunderhill = 25 hours...

i'm not sure what your normal racing season looks like, but the 24 hour type races are longer than the regular season by just a little bit.
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Old 06-24-10, 01:08 PM
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I've only done sprint races to date so this is a lot of uncharted territory in the tire area. If nothing else we'll learn a whole lot and have a #@itload of fun!

I am certain the car is mechanically up to the task as it hasn't had a whiff of a problem going on two years. And the problem it had then was a stupid error on my part. It receives preventative maintenance religiously and will have a checklist inspection prior to this race. No looking back now as the entry fees are paid!!!!
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Old 06-24-10, 03:52 PM
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Originally Posted by Bud Scott View Post
I've only done sprint races to date so this is a lot of uncharted territory in the tire area. If nothing else we'll learn a whole lot and have a #@itload of fun!

I am certain the car is mechanically up to the task as it hasn't had a whiff of a problem going on two years. And the problem it had then was a stupid error on my part. It receives preventative maintenance religiously and will have a checklist inspection prior to this race. No looking back now as the entry fees are paid!!!!
yeah its f-ing awesome...

our car prep is a bit nutty, but the honda is a POS so it needs it...

we buy ALL new bearings, preferably and oem japanese brand. NEW axles (no need for the 7), new ball joints, tie rods, we did the new rack in 2007.

then we repack all of the axles and bearings with redline grease (or similar high temp synthetic). its NOT an option, you need to do it. i think the rx7 people actually bring a spare set of struts already built

the alternator is a 50 hour part, we replaced in 2007, and midway thru 2009, it died completely, and we did some battery swapping.

the trans on a honda is a 50ish hour part too, we bought NEW, and it did 2007, 2008, and most of 09, and its dead. its replacement lasted like 45 minutes...

we run performance friction pads, and they last the whole 25....

ideally you want a complete extra suspension, radiator, trans. we always get hit by something, in 2007 it was a protege, they broke a taillight, and it folded our frame 45 degrees! we actually pulled it out, and kept driving.
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Old 06-26-10, 08:08 PM
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FOUR sets of tires for a Chumpcar race? Uhhh why? Why not just run street tires like all the cars running in spec (everyone else will be on >200 treadware street tires)? The rest of the cars you will be running with on the track will be worth less than the tires you would use in this one race. Most of the chumpcars will be on StarSpec's, DZ101's, or RT615's if they want to be compedative. If its a rough track and a heavy car with driver's that lock them up you might need two sets of starspecs/615s. DZ101s have lasted two races before.

Also, you will love it. Night racing is amazing. The ChumpCar crew is great. Everyone is there to have fun. Let me know if you have any other questions.
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Old 06-27-10, 04:42 PM
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Would love to run on any of those types you mentioned! However they do not make anything in a 205/60/13! About the only thing I have seen is a Sumitomo in our size. At a treadwear rating of over 300 its not exactly ideal for track use even in this environment.

We are formulating a strategy to account for tire wear and use of our existing stock (two sets BTW) of race rubber. At least our plan sounded good after a six pack and some margaritas.......................
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Old 06-27-10, 07:25 PM
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Originally Posted by Bud Scott View Post
Would love to run on any of those types you mentioned! However they do not make anything in a 205/60/13! About the only thing I have seen is a Sumitomo in our size. At a treadwear rating of over 300 its not exactly ideal for track use even in this environment.

We are formulating a strategy to account for tire wear and use of our existing stock (two sets BTW) of race rubber. At least our plan sounded good after a six pack and some margaritas.......................
we noticed you could start the race, pull the car in at dinner time, go and have dinner, a couple of drinks, get a good nights sleep, come back the next morning

and STILL finish ahead of any of the ESR cars...
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