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Discussion Starter · #1 ·
I went to a local SCCA autocross last weekend and I was a little dissapointed in my cars performance. I had a fast lap of 65.6 and was averaging around 66 to 67 seconds a lap. I never looked at the speedo but it felt like top speeds were around 65 MPH. There was another Cobra there but the driver had never run a autocross before and he was having trouble with spinning out even with "R" compound tires. I am running Kumho ECSTA Supra 712's 275/40/17 in rear and 245/45/17 up front with about 27psi cold. I was running pretty close times to a newer Trans-AM and a Fox Body Stang and both were on "R" compound tires which probably helped a lot on the old airforce airstrip in Pensacola. The track was covered in a lot of fine gravel and sand which made it almost like a dirt track in areas. There was a 2001 Z06 vette with Kumho Victoracer tires and he was running laps around 59 seconds.

Maybe my times were respectible with my limited experience and street tires but I was wondering how much better tires would help? I was told the tires were good for 2 to 5 seconds per lap?
 

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you didnt say how much experience you have but ill say this at least 1,000 more times in my life:

you dont need to spend money on the car to autocross as a beginner. it can actually inhibit your learning.

drive the car in 20 or so events first. autocross is much more about the driver than the car. there are few FFR drivers in the country that can beat a good stock miata driver.

the FFR is not an easy car to drive and a worse one to learn on. things happen so fast and it doesnt handle very well until there's a lot of tuning.

ride with the TOP drivers in your region and have them ride with you. work very hard to learn how to autocross. after a year or so, then maybe you can start to worry about the car setup. until then, changing the car will just confuse the learning process, and you may be setting up the car in response to novice (i.e. bad) driving habits.

if anyone wants to run seriously in my region, i will work hard to develop you and the car. (i compete in a very team-based class and its hard going solo)

if you check the results from last year's AMCC, you will see i beat a well known cobra racer in his sway bar, big motor, IRS car, and i was in my "model T" 4 link stock motored car. if i was in a miata i would have beaten him on sunday too


-james
2002 SFR-SCCA OSP Open Champion
SCCA autocross instructor 2000, 2001, 2002 SFR schools

[ October 25, 2002, 12:30 AM: Message edited by: Ophitoxaemia ]
 

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Let me ask some basic questions:

1.) What is your set up? Live axle, IRS, 3-link, coil overs, spring rates, etc.

2.) How many times have you autocrossed?

Here's some ideas.

Autocrossing takes practice and to be good it takes more driver skill than car set-up. In most cases, you won't be able to drive beyond yours roadster abilities until you've had at least a years worth of regular autocross races under your belt.

Slicks are tricky for beginners. I recommend running street tires to new comers. They squeal more and the feedback is more lateral. Slicks or DOT racing tires have a high limit of adhesion, but will let go without much warning. Spinning is part of learning your cars limits. But I think most new people should work on the line and not the speed. If you don't spin for 3-5 events, great news. Then start pushing more and you'll end up backwards a few times too. But that's OK, your times will be better too.

A badly set-up cobra can be a hand full. A live axle car without a 3-link is pretty tough to drive fast without working your butt off. I think a lot of guys get upset with cobras because they don't post great times. When all they need is seat time and have someone help with the cars setup.

What I'm saying is stick with the street tires until you're within 2 seconds of your competition. Then you need DOT racing tires. By the way, replacing flat spotted street tires is not fun, so find an empty parking lot and practice braking in a straight line, then try some braking while turning a little. Learn where your car will lock up the tires and then try to test yourself with braking points.

Another fun practice exercise is to run a local SCCA practice race. They allow you to stop and go and try corners several times. Learn how to trail throttle over steer your car and how to kick the rear out and control it. Learn how to push the front tires by using the gas pedal too. This helps you learn how much speed you can or cannot carry into corners.

The best thing you can do is make a log and only change one thing at a time on your car. Then try it out. I would start with lowering your tire pressure to 23 psi in the front.

Good luck and let us know how it’s going!

Bill
 

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Discussion Starter · #4 ·
Well actually my car only has a few FFR parts on it(windshield, tail lights, fuel filler and mirrors). It is a Hunter Cobra with a Vette IRS, front and rear sway bars and 4 wheel disc brakes.
The car handles great and on a road course I love the way the car handles. The rough and sandy ancient airport runway is another thing entirely. I think my street tires are a big handicap and on a autocross you cannot use too much V8 power as you are on the binders as soon as you hit the throttle. I plan to run a few more autocrosses but I really like to run road courses as that is where the Cobra shows its stuff. I guess with time I should be able to shave a few seconds off my times but to run with that Z06 I will need TIRES.

The other cobra was a EM with very wide R compound tires but I suspect the tires have been heat cycled too many times and are just as hard as street rubber.

At the DSCC Gainesville, FL event last winter(if you call 80 degrees winter) I was within a second or two of Engineer Ed's car on similar tires but he had more motor(347 vs 302) and better gearing(3.73 vs my then 2.73's). The same Z06 that was running at the Pensacola autocross was at gainesville and he was about 5 seconds faster than me but he was runnig R compounds. there was a big block superformance with R compounds and he was running about the same times as the Z06 and that was with a driver with less exzperiance than the Zo6 driver.

everyone says to run fast you need good rubber and although my tires are great street tires they do not compare to the Victoracers.

Learning how to cut the tight corners and not mow down the orange Ice creem cones is a skill in itself. I do not recall any cars running on street type rubber running clost to my times but when a 3500# trans am is running faster it has to be the R compund tires he was running.

Cobras are not their best on really tight courses.

Oh yeah the fastest street car there was a new Honda S2000 on Victoracers. I think he was about 1 second faster than the Z06
 

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Its very much a learning thing. We constantly get new guys with outrageous cars, (Z06, Viper, M3, f-cars) who get beat by the local Scirocco driver who does it all the time.

I autocross constantly, and know my Cobra could be faster than my pip-squeak powered Miata, however, I have V700's for it, and they equalized the 200HP imbalance! Now if I had a set of Hoosier a-x tires (and rims) for the Cobra, there would be no contest...
 

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James, who are you referring too? I sure don't see the AMCC results on line for last year or this year. If you are referring to beating the TTOD car on Sunday I doubt you could have done that in a Miata ;)

[ October 25, 2002, 12:00 PM: Message edited by: Chick FFR Racer ]
 

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well for one, the ultra fast slick shod vettes/mod cars didnt cruise on their junk tires, for fear of being beaten by david again! due to the 3 link, the FFR's cobras did much better in general, and scott and jeff peterson did very well indeed. david laid down an eye watering run on sunday. my car had some problems but mostly i didnt drive particularly well.

it was a funny course, so slaloms, no tight spots and no slowing down.

the teams david, sherry and i were on all won trophies (jeff peterson was also on my team and did VERY well with the 3 link and street tires).

sherry and kirk said jack and coke was a chevy drink- id never heard that. the raffle was very long and we didnt win anything.

-james
 

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They trophied the top 10 teams out of the 20 competing. The following Cobra drivers were on trophy teams:

David Borden
Kevin Terpstra
James Creasy
Jeff Peterson
Jonah Tollefson
Sherry Grantz

The team I was on missed the 10th place spot by .039 seconds........

It was a very fun weekend.
 

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Bobby McCoy owns the EM and was on my team. He was running a 524 cu BB motor. He is a real nice guy.
 
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