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Author Topic: The Care and Feeding of RA-1s
jeopardyracing
Member

Region: WDC
Year : 1995
Posts: 50
Status: Offline
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I'm an HPDE weekend warrior with just 19 track days of experience and long term dreams of graduating to Spec Miata (but no budget yet for it). I plan to run HPDEs again next year, and am graduating from Falken Azenis, which have lasted me 11 track days over the last two seasons and are now pretty much out of tread, to RA-1s next spring.

For the Azenis, I have learned some "care and feeding tips" such as "this tire can have surprisingly good grip but if you over drive the tire, it gets greasy and really goes away until you back off to about 90% for a half a lap or so," "if blue rings appear on the outside of this tire, you need more negative camber," and "don't expose this tire to near freezing temperatures" etc etc etc.

What would be the "care and feeding tips" I need to learn when I get a set of RA-1s? For example, I've read things about properly heat cycling the R888s the first time, and such. Is the "break in" of the RA-1 just as important? Does it go off if you over drive it? Any Care and Feeding tips appreciated [Smile]

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Team Saferacer

Region: Kansas City
Car #: 70
Year : 95
Posts: 477
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Lots of variables possible here, but let's assume you start with a 4/32 shave. IMHO, the tire will actually last longer and perform better with a shave, rather than starting a full tread depth. A full tread RA1 will squish around, overheat, and chunk itself to death.

Heat cycle the shaved tires once...full heat, no sliding and let them rest at least 24 hours. 2' camber ok, criss cross rotate after every track day (4 sessions or so), then flip them on the rims when you see camber wear.

You may need to play with starting pressures to achieve 38 pounds hot pressure (right off track, no cooldown lap) measurement, but this is where the tire will give you the best performance. Almost certainly need to stagger starting pressures for each corner of the car and will vary by track. Bleed them down as the day gets hotter, and keep them shaded while parked in the paddock.

This tire can be overdriven and go off, but if you are getting two years and 40+ sessions out of your tires, you are probably not driving them that hard, which is a good idea without a roll cage and the full safety features of a race car.

Not advisable to test the ultimate limits of your daily driver, but as you go faster, the RA1 will not give you the longevity you describe on the Falken. The RA1 should be ok until you cord them, but watch for cupping before that, which is a nasty habit for the RA1.

--------------------
Mike Asselta
http://www.saferacer.com

jeopardyracing
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Region: WDC
Year : 1995
Posts: 50
Status: Offline
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Thanks Mike!

andrew_anderson
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Region: SC region and buccaneer
Year : 1991
Posts: 184
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I wouldn't really advise switching to R compounds until you get some more safety in your car, like a cage, somewhat reiterating what Mike said.

RA-1s will last a long time. Is your car a Miata?

--------------------
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jeopardyracing
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Region: WDC
Year : 1995
Posts: 50
Status: Offline
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Yes, I have a 1995 R Package. It has the Hard Dog rollbar, seats and 5 point harnesses. I use a HANS too.

How much will my lap times drop with R compounds? The Falken is an interesting tire in that it can be surprisingly quick if you look after it and don't over drive it. I've come across R compound Miatas during these track days before and hung onto them surprisingly well when I am careful with the Falkens and don't heat them up. But it's hard to tell if a carefully driven Falken is actually surprisingly close to R compounds or if these R-compound shod cars are not running to their full potential.

For example, weekend before last I was brawling with a stripped out 1.6L running 40 treadwear slicks and we were running about the same lap times. We were running 1:29s at Lightning (with standing water in Turn 7 after the morning rains, but the rest of the track dry). The 1.6L driver had lots of experience and the car looked to be well driven to me.

So I wonder - will my lap times drop enough with R comps that the safety situation will change that much over the Falkens?

andrew_anderson
National Member

Region: SC region and buccaneer
Year : 1991
Posts: 184
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Well, think of it this way.
The R compounds will allow you to:
- Corner faster
- Brake in shorter distances
- and in some situations accelerate better.

The slip angles of street tires and r compounds are different. The way the grip falls off is the biggest difference if I am correct.

Think of a parabolic curve.

--------------------
Dish NetworkNew Dish Network customers receive a $40 rebate if you are an SCCA member!
Race Engineering. Championship winning engines.
Carbotech Brakes
Panic Motorsports
Low Country Communications
2343 Main HWY
Bamberg, SC 29003
800.371.6709

   

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