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Autocross learning curve

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Old 04-29-03, 08:21 PM
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Autocross learning curve

I have a question for you autocrossers - at what point did you start getting into a groove where you run competitive times (let's say at mid-size events). That is, how long did it take to get really fast? Did you hit a plateau early on or were gains steady over time?

This addiction is mostly about driver skill so I'm working on it, but I wanted to get a feel for how long it took most folks to get the hang of it.

My AX experience: I autocrossed a few times over the last few years, at various club events and took an Evolution school last year (which was a blast). This year I'm going all out with about 2-3 events a month through November including an SCCA school, a BMWCCA school, and hopefully another Evolution school.

My setup: Not that it matters at this point, but my FD is well equipped with all the necessary suspension and engine mods to make the car go like stink. Several instructors have exited the car saying "holy **** this car is fast!" Oh, and I'm using Toyo RA1's just because I just can't put the power down with regular street rubber. I can tell that I have plenty to learn before it would be worthwhile to run full race rubber. So what do you coneheads think?
Old 04-30-03, 08:19 AM
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I could probably right a few pages about this, but will keep it simple. If you feel you have plateaued at any time that is the point to take another class. Drivers are athletes too and a good coach can make all the difference. Instincts only get you so far, to really succeed you have to work with someone who knows more than you.

If you feel you left some time out there, you did. I feel like that all the time but the real question is WHY did I leave time out there? That's where you need help.

On a smaller note how have you developed the car? You already know horsepower means little in autox, setup is everything. But if somebody else can get in your car and drive it faster than you, then you have work left to do!

DamonB #99 Super Stock and working as much as he can
Old 04-30-03, 09:03 AM
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Originally posted by DamonB
[B]On a smaller note how have you developed the car? You already know horsepower means little in autox, setup is everything. But if somebody else can get in your car and drive it faster than you, then you have work left to do! [B]
DamonB: PFS "developed" the setup - which I purchased with the instructions that I wanted a balanced car that I could run on the street, the track, and the autocross course without having to tinker with it all the time. It's not the "ultimate" setup for any of the above, but I have been very happy with the compromise between these 3 intended uses. No one has driven my car faster than me, but I have driven in other "slower" cars with National caliber drivers and recognize that I can kick it up a notch... Also, I don't think that my AX skills have plateaued, but as with most forms of training I recognize that it happens.

That being said - so when did you guys start getting fast?
Old 04-30-03, 09:20 AM
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My best improvements came from driving other cars. Co-driving is the best way for me to hone my skills. Driving a FS '94 Camaro Z28, it really makes you focus on being smooth and setting up the car for all the transitions. Having a co-driver in my car also pushes me to be faster. I guess I'm also lucky to have many extremely fast drivers in my local club. When you've got an Erik Strelnieks and a Dan Pedroza pushing you around, it forces you to get better.

And a VERY close second place goes to the brand new Kumho's. Brand new race rubber is eons different than used stuff and, from what I've been told, a lot stickier than the road race rubber (for different reasons though ... it takes a lot more heat to get road race rubber to temp ... you usually don't see enough on an auto-x course). With the sticky stuff, I'm a lot more aggressive with my brake points and entry speed.

Lastly, you almost always feel like you've left some time on the course. When you start to feel that, I think that's an indication that a) you're getting better, b) you still have stuff to learn, and c) you're still not 'at the limit' in all the spots possible. I'm almost always mentally barraging myself with the "be aggressive" mantra.

Although, there are some points I have to argue. In stock class, it's mostly about suspension. Once you step out of stock class, horsepower is every bit as important; with low-end torque being the BIG multiplier there. I run in SM2, and when I was basically a SS car except for the PowerFC ... I got roasted. One thing I also noticed about the top guys in the SP and SM classes ... they are ALL ABOUT saving weight. Every little thing they can do to shave off weight, they do.

Ok, I guess I've babbled enough.

-Don SM2 #81/181 .... still chasing around Turbo Miatas
Old 04-30-03, 10:02 AM
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Originally posted by redrotorR1
Once you step out of stock class, horsepower is every bit as important; with low-end torque being the BIG multiplier there.
I still disagree Winning H Stock car at Houston ran a 109.793 for the weekend. Winning SS ran 103.748 and winning SM2 ran 106.417. Those times are over two days so the daily difference is half that. That means 3 seconds between HS and SS. The 115 hp Mini was only 3 secs off the 400 hp Z06 on a 50+ second course???? Yes 3 secs is a good gap but it took 300 more horsepower to get it! 100 horsepower per second, what a bargain!

I will admit to neglecting suspension and tire size, but you will always go faster with tire and suspension unless the power is truly grossly different.

Last edited by DamonB; 04-30-03 at 10:08 AM.
Old 04-30-03, 10:04 AM
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Originally posted by Coulthard Fan
That being said - so when did you guys start getting fast?
To me "fast" means being in the top 10% anywhere I go. I am not fast yet.
Old 04-30-03, 10:24 AM
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Originally posted by DamonB
I still disagree Winning H Stock car at Houston ran a 109.793 for the weekend. Winning SS ran 103.748 and winning SM2 ran 106.417. Those times are over two days so the daily difference is half that. That means 3 seconds between HS and SS. The 115 hp Mini was only 3 secs off the 400 hp Z06 on a 50+ second course???? Yes 3 secs is a good gap but it took 300 more horsepower to get it! 100 horsepower per second, what a bargain!

I will admit to neglecting suspension and tire size, but you will always go faster with tire and suspension.
3 seconds. That's an ***-whoopin', if you ask me. But more appropriately, I should have been more precise. Horsepower-to-Weight ratio is as equally important as suspension ... as you should know, Z06-chaser.

When did I get fast? .... I was born fast ...
Old 04-30-03, 10:35 AM
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Originally posted by redrotorR1
3 seconds. That's an ***-whoopin', if you ask me.
I wholeheartedly agree to the whoopin. My point was it took 300 more horsepower to do it! How much money in motor does it take to get 100 more hp from it? 150? 200? You see where I am going?

3 seconds on a 50 second course. The car with 300% more horsepower was only 6% faster. Ugh. Surely horsepower is not the difference

Last edited by DamonB; 04-30-03 at 10:55 AM.
Old 04-30-03, 11:09 AM
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And if you want to use power to weight it breaks down almost exactly the same

Mini 22lbs/hp
Z06 8 lbs/hp

275% difference.
Old 04-30-03, 11:27 AM
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Originally posted by DamonB

DamonB #99 Super Stock and working as much as he can
You run Super Stock with those mods? Hmmmmm...
Old 04-30-03, 11:28 AM
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dubble dubble post
Old 04-30-03, 11:55 AM
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I'm not sure whether you are talking about being in the top ten out of 50, 100, and whether you are talking about raw times or PAXED times. I think that feeling good about your performance is the thing that most competitors quest for. There are some of us that will only be satisfied winning our respective class or getting TTOD, and will spend countless hours on set up to get there, but that achievment at an autocross with 50-100 competitors is going to take seat time.
Since seat time was really your question, for me running a 87TII in ASP(back in the day), it took a couple years of 8-10 events a year to consistently place in the top three in my class. That said, I am not a natural talent.
In contrast after being out of it for about 5 years, and coming back it was a half a dozen AX to get back in there.
First, I would say the key, starting off, is a solid well prepared car, which you seem to have. Then, with the assistance of an experienced driver making changes to your car to address gross handling problems(primarily heavy under/oversteer. Once you have a balanced car, resist the temptation to constantly change things between runs(tire pressure, shock valving, sway bars, etc). By keeping the set up essentially static, you can focus in on technique. Every car has strengths and weaknesses. You want to learn techniques to minimize the weaknesses of your set up, and the strengths of the car will naturally follow.
Let me give you an example. I currently drive a 97TT Supra in SM2. This is a very powerful, very heavy car(3750lbs). With my current set up I still have an unacceptable amount of understeer at the limit. I have focused my driving efforts on left foot braking, and using trailing throttle understeer to rotate the car. In doing this I have learned to use my power to overcome the understeer problem thus going faster.
One thing you should seriously consider is running your turbos in parallel as opposed to sequential. For an experienced autocrosser sequential is a headache to be dealt with. For a begining autocrosser it is down right dangerous at the limit. We had a first time autocrosser destroy the rear of his FD this weekend. He was in a fast sweeper traveling too fast, just as he approached the limit of traction the second turbo hit causing the rear to start to come around, he then lifted throttle completing his destiny. You can simply keep the revs up keeping the 2nd turbo spooled, but without other skills you may find this impossible on a tight AX course.
Hope that helps a little. Basicly get the car balanced, and then focus on one technique at a time. With natural talent you may be competitive within a half a dozen AXs, or if you are like me, it may take a couple of seasons.
good luck, and have fun, Carl Byck
Old 04-30-03, 12:01 PM
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Originally posted by DamonB
3 seconds on a 50 second course. The car with 300% more horsepower was only 6% faster. Ugh. Surely horsepower is not the difference
Well, nobody said it was a linear correlation ....

Suspension and tires are a large part of the equation, but it's folly to think that horsepower has nothing to do with it. If that were the case, Jason Saini (BS S2000) and his $10K shocks should be king of the hill.
Old 04-30-03, 12:11 PM
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Originally posted by in2twins

One thing you should seriously consider is running your turbos in parallel as opposed to sequential. For an experienced autocrosser sequential is a headache to be dealt with. For a begining autocrosser it is down right dangerous at the limit.
I disagree. After driving a couple single turbo RX-7's, I am thoroughly convinced that sequential twins is the way to go. The FD's natural low torque curve is painful at times ... going non-sequential only adds to that pain. Waiting until 3500rpm for boost is intolerable at times. I find that, at least with the RS/RZ turbos, the transition is fairly seamless and power difference between primary and both turbos translates well on course. For newbies, well ... yeah, they're going to loop it a bunch until they get the hang of rolling into the throttle, instead of stomping on it. And, if they want to keep their car in one piece, just don't be a hero and try to power your way out of a spin. Ok, off-topic.
Old 04-30-03, 12:36 PM
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Originally posted by in2twins
First, I would say the key, starting off, is a solid well prepared car, which you seem to have. Then, with the assistance of an experienced driver making changes to your car to address gross handling problems(primarily heavy under/oversteer. ...
Forgot to add - I run in SM2 as well. The car is setup very neutral with a very slight tendancy towards understeer. I run with the same settings every time on the suspension/tires. (Koni single's 1/2 turn back from full hard and 38psi in the tires.)

One thing you should seriously consider is running your turbos in parallel as opposed to sequential. For an experienced autocrosser sequential is a headache to be dealt with. For a begining autocrosser it is down right dangerous at the limit. ...
I love the sequential on the street though, and the 99 turbos just have such awesome throttle response I don't want to give it up. Besides, the transition is smooth so that it has never cought me out on the track or on the AX course. Maybe that driver had a nasty spike?

With natural talent you may be competitive within a half a dozen AXs, or if you are like me, it may take a couple of seasons.
Thanks for the tips. In terms of my results so far: At the first SCCA event this year I was 4/12 in SM2 class, and if I was registered as a novice (which I think I am supposed to be) I would have had the fastest time of that group of 33 by half a second. Overall, my indexed time was right in the middle of the field. At a BMW school last month I was FTD by over a second on a 50 course, but that was a fast course against other rookies in mostly stock BMWs.

Last edited by Coulthard Fan; 04-30-03 at 12:39 PM.
Old 04-30-03, 01:01 PM
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Originally posted by redrotorR1
Well, nobody said it was a linear correlation ....
Speaking of math, I was looking over the results and Damon needs retake that basic math course again .... 6-second difference between the Mini and the Z06. 275% HP delta for a 12% gain on course. That sounds about par-for-the-course.
Old 04-30-03, 01:14 PM
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As for the sequential issue, I guess I am reacting to this one persons experience. I know in my supra as your power level increases the transition becomes odvious, where as at stock levels it is transparent. Red, try waiting till 4000rpm for full boost, recieving 200+rwhp in 750rpm, and running out of revs at 7000 rpm. I just cannot understand why Supras are not popular autocross cars ... Take a look at WARGASMs dyno comparison page, and look at Silvinos Supra power curve. You will see what I mean. In a single turbo Supra the power goes from 250rwhp at 4000 to 550-700 by 5500rpm! Anyway, I cannot wait to get my seven done, and back on the track.
Later, Carl
Old 04-30-03, 01:28 PM
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Originally posted by redrotorR1
Speaking of math, I was looking over the results and Damon needs retake that basic math course again .... 6-second difference between the Mini and the Z06. 275% HP delta for a 12% gain on course. That sounds about par-for-the-course.
That's a six second difference over two days of competition, so only a 3 second gain for each day which is 6%.

Here, you dropped this on your way out:

Boy I crack myself up sometimes.
Old 04-30-03, 02:40 PM
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Hey, you found my hat ...
Old 04-30-03, 02:52 PM
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Now can you tell me how many teaspoons are in a cup? I am supposed to cook dinner tonight.
Old 04-30-03, 03:21 PM
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Coulthard Fan, I would say after my first 25 events I found that my gains tended to be much smaller. Then I took Evo 2 and started making progress before once again reaching a plateau. For myself I can't fix something if I don't know what's wrong, that's why I go back to school when I feel I am stagnating.
Old 04-30-03, 03:37 PM
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Originally posted by DamonB
Now can you tell me how many teaspoons are in a cup? I am supposed to cook dinner tonight.
48 ... but you might want to double-check that.
Old 04-30-03, 04:11 PM
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Damon,

I see your wife/GF has trained you properly

hehe

PaulC
Old 04-30-03, 04:33 PM
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Originally posted by DamonB
...(something mathematic)... so only a 3 second gain for each day which is 6%.
Yes, but what is the standard deviation of the results for the event?

... I should be studying for a grad school final right now that relates to application of statistical data to corporate tax revenues, but instead I am thinking of how to lower my autocross times and changing my avatar to represent my driver. ...
Old 04-30-03, 04:48 PM
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Originally posted by Silkworm
Damon,

I see your wife/GF has trained you properly

hehe

PaulC
Yep. I cook about once week, she eats it and then does the cooking herself for another week


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