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Hoosier R80 R100 on MK2 RS

Old 05-13-2010, 01:49 PM
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Bob Rouleau

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Default Hoosier R80 R100 on MK2 RS

My tire dealer has told me to use the Hoosier slicks on my '10 RS. Wheels are 18 inch dia. Apparently they are the spec tire for the Cup series.

Does anyone know what hot pressures I should shoot for? I've used the R6 but this will be a new experience.

Best,
Old 05-13-2010, 02:28 PM
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Z06
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Bob, what spec series?

The Patron series uses Yokohama slicks...maybe consider them..they are an exact fit and they are that good!

But the other concern is the ABS causing the Ice Mode?!
Old 05-13-2010, 03:19 PM
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85Gold
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Originally Posted by Bob Rouleau
My tire dealer has told me to use the Hoosier slicks on my '10 RS. Wheels are 18 inch dia. Apparently they are the spec tire for the Cup series.

Does anyone know what hot pressures I should shoot for? I've used the R6 but this will be a new experience.

Best,
Bob,

When we ran them on the 996GT2 R100's we shot for 30psi Hot. Jeff Spears @ Hoosier is the man for any questions.

Peter
Old 07-18-2011, 09:10 PM
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Hoosier_Daddy
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Any more on this?

I'm headed out to the Glen in a couple of weeks and will be using the R80 up front and R100 in rear. I've lots of experience with the Michelin and Yoko slicks, but this will be my first on the Hoosiers. Like to know the thinking on both cold and hot psi.

TIA

Old 07-18-2011, 09:23 PM
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mdrums
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I'm seeing more guys at the track in the race groups using Yoko slicks these days. Ask ViperBob on these forums about them he has 2 guys using them and they like them a lot better than the Hoosiers they use to use.
Old 07-18-2011, 09:38 PM
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24Chromium
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We've got folks out here using the Yokos as well. Saw some with red lettering on them. R6s are still the most popular on the GT cars.
Old 07-18-2011, 10:02 PM
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Originally Posted by mdrums
I'm seeing more guys at the track in the race groups using Yoko slicks these days. Ask ViperBob on these forums about them he has 2 guys using them and they like them a lot better than the Hoosiers they use to use.
The Yoko slicks are more than the Hoosier slicks. I've run the Yoko slicks for many years... good tire but $500-600 (+/-) more than the Hoosier radial slick per set. I buy a few sets and I've saved the money for another set. (Plus I am running the 19 inch wheels.)

Please guys -- this is not a thread about what tires are better... I would like people with experience to share what they know on the Hoosier radial slick in the R80 or R100 compound.

Thanks
Old 07-18-2011, 11:02 PM
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Ok I'll shut up.... ;-)
Old 07-19-2011, 12:03 AM
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Too funny Mike.....

OK I've run the R80/R100 combination. I know that Hoosier tells everyone to run them at 30 hot and that seems to be a good place to start. I would go out dead cold at 24 front 23 rear and bleed them down to 29-30 after 5-6 laps. If you were going out cold for a race I would drop to 22/21....

I found them to be very slippery when cold so take it easy for a few laps before you push them. I got over 20 HC's on that set remarkably....
Old 07-19-2011, 10:06 AM
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Originally Posted by jrgordonsenior
Too funny Mike.....

OK I've run the R80/R100 combination. I know that Hoosier tells everyone to run them at 30 hot and that seems to be a good place to start. I would go out dead cold at 24 front 23 rear and bleed them down to 29-30 after 5-6 laps. If you were going out cold for a race I would drop to 22/21....

I found them to be very slippery when cold so take it easy for a few laps before you push them. I got over 20 HC's on that set remarkably....
That's what I've heard; 30 hot is the target. I will speak with Hoosier prior to the weekend, but figured there be a couple of people who've run them on the forum -- thanks for the info.

20 HCs is remarkable and consistent to what we've been told with about the tires. Actually, seems to be about the same as R6s based on my previous experience. (20-24 heat cycles)

I usually see about a 10 psi rise for a 20 minute session; I'll look at that 20 to 21 psi range cold start. I have not been to the race track with my GT3 yet so it's both a new car and tire for me.

Should be fun.
Old 07-19-2011, 10:43 AM
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amaist
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Originally Posted by Hoosier_Daddy
I usually see about a 10 psi rise for a 20 minute session; I'll look at that 20 to 21 psi range cold start.
I did that and ruined the fronts. The first few laps at such a low pressure ruin the sides of the tire. You need the center of the tire to hold it up.

Start at 24 and bleed them down as needed.

29 front 30 rear or something in that range as you get used to them and figure out what works for you.

Good tire. Went away for me when I corded it. Stayed together until then.
20 HC is about right.
Old 07-19-2011, 11:52 AM
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Seth Thomas
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30 hot is a good target and starting at 24 a good starting point. With 24 starting and bleeding down as needed the tire will have a little bit more support in it coming out of the pits. These tires don't like to be beat on right out of the pits with a low tire pressure in them. Give them a few easy laps to get some heat and pressure in them before really driving hard on them. This will help them to last longer and keep from cording.
Old 07-19-2011, 02:04 PM
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Originally Posted by Seth Thomas
30 hot is a good target and starting at 24 a good starting point. With 24 starting and bleeding down as needed the tire will have a little bit more support in it coming out of the pits. These tires don't like to be beat on right out of the pits with a low tire pressure in them. Give them a few easy laps to get some heat and pressure in them before really driving hard on them. This will help them to last longer and keep from cording.
Outstanding -- Thanks Seth. (and amaist)

Old 07-19-2011, 03:19 PM
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I've run the R80 front and R100 rear combo' as well as R100s all around. We targeted 30psi hot at first but found an unusual wear pattern on the fronts. Increasing the hot target to 32psi worked better and resulted in more even wear across the surface of the tire. The heavier weight of the street GT3s over a Cup or race prep'd car called for the higher pressures. Alignment settings are also a factor. It seems we had the front camber at 3.25 degrees negative and rear was 2.25 negative as I recall. Tire widths were 250 front and 305 rear on a 2008 GT3.
Old 07-19-2011, 04:05 PM
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Originally Posted by MSRPorsche
I've run the R80 front and R100 rear combo' as well as R100s all around. We targeted 30psi hot at first but found an unusual wear pattern on the fronts. Increasing the hot target to 32psi worked better and resulted in more even wear across the surface of the tire. The heavier weight of the street GT3s over a Cup or race prep'd car called for the higher pressures. Alignment settings are also a factor. It seems we had the front camber at 3.25 degrees negative and rear was 2.25 negative as I recall. Tire widths were 250 front and 305 rear on a 2008 GT3.
I've been down that road before having run slicks on the heavy 996 Turbo. Seems most of the advice the manufacturer's would tend to give pointed toward "a little higher" pressure due to the weight of street cars. (32-34 range) I usually kept track of the tread temp with the pyrometer and don't recall ever going above 220 degrees with most common temps in the 200 degree range... so we never really worried about the psi too much. With that said, I seemed to have the most success with low-mid thirties psi with both Michelin and Yoko slicks... I would bleed down after the first session of the day from the high thirties. I am afraid of over heating the shoulders if the pressures are too low. I suspect the camber will be -2.5 front and -2 rear, but we have not aligned the car yet.

No matter what some my think -- I feel 3000 + pounds is pretty heavy.

Glad I posted to this thread... getting good feedback.

H_D

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