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Author Topic: Setup for R888's
Muda Verified Driver Made Donation to Website
ComingToAMirrorNearYou

Region: WDC
Car #: #23
Year : 1991
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Does the reported need for less camber for the R888's make the addition of the '99 hats less of a priority?.

I thought the primary benefit of the hats was to allow a lower ride height and the resultant greater camber with shock travel equal to a higher setting without the hats.

Does the lower ride height alone justify the mod?

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Muda Motorsports
"We're all here 'cause we're not all there."

Jfornachon Verified Driver
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Region: socal
Year : 1991
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I will allow for a lower center of gravity while still maintaining enough travel.

I asy yes, unless it is going to keep you offthe track. Then I would just sart saving for the hats and FCM kit.

Have a great day,
Jared

George Munson Verified Driver
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Muda,

I can't speak for everyone but in the short time ( one race weekend ) I've had on the new tires the setup is about the same as RA1's. Most who pulled camber out, put it back, and my tire pressures were run the same. I must state I'm not a front runner but I'm getting closer. Maybe some of the big boys will share some tips.

PedalFaster Verified Driver
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Year : 1995
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Bump. Anyone else willing to share initial setup tips and impressions?

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Stephen Hui - '95 SM #86, Northwest / Oregon Region SCCA

Glenn Verified Driver
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We tested R888's last weekend at Roebling Road. I do not recall any reduction in camber by any of the drivers. The sidewalls are VERY stiff so in theory a reduction in camber should not hurt. Also the tire profile looks like the outside 2 inches or so slope away towards the shoulder. I'm guessing there is a different compound there. Most drivers noticed an initial turn-in bite that was better than the RA-1's they also commented that the grip went away mid corner. Also the tires a r very susceptible to center section wear. Guessing pressures are too high although the handling is reportedly OK at the higher pressures.

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Glenn
Crew chief Meathead Racing, NE Region Sales Division Race Engineering, The GOLD standard in SM engines, Occasional race slave for OPM Autosports

Gatoratty Verified Driver Made Donation to Website
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Year : 1992
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Glenn

Do you know what the shave depth was on the tires?

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Paul McLester

Mark McCallister Verified Driver Made Donation to Website
Just graduated from novice to rookie!!

Region: Central Florida
Car #: 40
Year : 1991
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I was going to ask the same question...those 888s that Tom was on when he was turning the 1:22s at Roebling last weekend...what was the initial status and history of those tires on that car??

I got temps off only my first session on the 888s (was getting tired by then!) :

LF 177 175 170 RF 146 144 134
LR 154 176 192 RR 160 164 158

Made adjustments after that to reduce crazy oversteer...the RF doesn't get to do any work at all in an oversteering car at Roebling. Those temps indicate too much neg camber in the LR, but I didn't see that previously on the RA1s, and we didn't make any camber adjustments, so I am thinking maybe that was a fluke...will see. Other thoughts?

Glenn Verified Driver
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Danny's car, the one Tom drove had about 10 heat cycles on them. Danny ran them in Florida and they were driven several times on Sat. The 192 number looks suspicious to me as well but if the lr was sliding AND you had too much camber it COULD be possible. We had a VERY hard time at Sebring getting ANY temp into the tires. We raised/lowered and still the temps were lower than what we used to. I did see several cars wearing the inside of the tire at PBR. Assumed it was the new pavement and sliding the car but could be a camber issue. Still too soon to tell we need a LOT more time on these tires to make definite statements

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Glenn
Crew chief Meathead Racing, NE Region Sales Division Race Engineering, The GOLD standard in SM engines, Occasional race slave for OPM Autosports

Glenn Verified Driver
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quote:
Originally posted by Gatoratty:
Glenn

Do you know what the shave depth was on the tires?

No not specifically, several sets had a lot of cycles but the set Skip ran was new. Tom can tell what the shaved depth was.

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Glenn
Crew chief Meathead Racing, NE Region Sales Division Race Engineering, The GOLD standard in SM engines, Occasional race slave for OPM Autosports

OPM AUTOSPORTS INC Verified Driver Made Donation to Website
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All of our new 888's were 3/32nd. Danny's tires were new at Sebring Nat and pretty well worn down. They would fall off pretty bad after 3-4 laps.

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-Tom Fowler-
OPM Autosports / SMAC MEMBER
http://www.opmautosports.com

Todd Lamb Verified Driver Made Donation to Website Series Champ
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From what I have been told this is the problem with the 888 - they fall off big time unless you are very conservative with them throughout the race. They are going to need to be shaved to 2/32 to be really fast, and they will wear quickly.

I think we're going to find the tire bill going up significantly this year....really is a shame, the RA-1 was a great spec tire.

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Mazdaspeed // SafeRacer // Traqmate // OPM Autosports // East Street Auto // Cobalt Friction
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Louis Interdonato
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It sounds like the R888 is not as good as the RA-1's. My question is why are we switching to a inferior tire? Why not keep the RA-1's. With the economy as bad as it is the additional cost for tires will hurt many racers.

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WDCR SM # 90 http://www.rpperformanceracing.com/

d mathias Verified Driver Made Donation to Website
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Unfortunately for me the money tree ain't blooming. Very limited dollars in the tire budget = very limited participation in 2009.

The real shame is that SCCA and NASA's tire choice may cause the unintended consequence of decrease entries from those of us that simply can't afford $600+ tires every (or every other) race weekend.

Waaaa

Dr.Dan Verified Driver Made Donation to Website
V8, nice! And good for you too!

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Our tire guy out here said to run them at a starting pressure of 37-38..come off about 44. that's what he said, I'm just the parrot..

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Daniel Mairani DDS...still here, just faster.
http://www.DanielMairanidds.com

motorrock
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quote:
Originally posted by Dr. Dan:
Our tire guy out here said to run them at a starting pressure of 37-38..come off about 44. that's what he said, I'm just the parrot..

I think that is the "new" ballpark

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philstireservice.com
philstireservice@aol.com

SamBarnett Verified Driver
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We concluded the same thing last weekend at CMP. The wear was not anywhere close to what we got on the RA1s. In addition we did not feel the grip level is quite what it was on the RA1s.

quote:
Originally posted by Todd Lamb:
I think we're going to find the tire bill going up significantly this year....really is a shame, the RA-1 was a great spec tire.



[ 02-15-2009, 09:50 AM: Message edited by: SamBarnett ]

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Race Engineering - Championship Winning Engines
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Vick Verified Driver
Do they sell spec training wheels?

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Year : 1991
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I don't understand much about tires (or anything mechanical for that matter) but I have a question. I thought that the R888 and the RA-1 were made from the same compound? Why would the newer tire wear so much faster?

Is it because of the greater amount of surface area that is hitting the pavement? Is it because of the higher pressures (and I guess temperatures) required to make this tire work? Was this discussed somewhere and I missed it?

The Toyo website claims that the larger contact patch makes for better handling under braking than the RA-1's. Any evidence?

Thanks in advance for the help with my rookie questions.

-Vick

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http://www.volko.com

wheel Verified Driver Made Donation to Website
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Tire patch is determined by the weight on each tire. By having a wider tire, you are not increasing the size of the tire patch, just the shape. The wider tire makes a wider patch that is smaller from front to back. This will change brake lock up and cornering forces. If the compound and structure of the tire is identical, the slightly narrower tire should brake better, but not corner quite as well. A wider patch would also need to be considered when you set your tire pressures and your geometry.
But, what do I know?
wheel

   

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