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Today I discovered oversteer...

...and loved it! Had an awesome track day at Mosport, and coming around turn 3 discovered I could let the tail hang out and easily get it back. Wow, talk about exhilarating! The only downside is that it's not the fastest way through such a turn. There's a fair amount of run-off there though (for Mosport, where there's little run-off anywhere) so it's one of the safest places to try it. At least I felt safest there.

It started by accident in a late morning session, then I spent most of the afternoon working on it, even though it probably cost me a full second or 2 in lap times. Maybe I'm doing it wrong - long right hand sweeper, 3rd gear, about 4500 rpm, I'd let off the throttle just past the apex, after cranking the wheel just a hair - maybe 1 degree - to tighten the turn and really load the suspension. The back would slide out a bit, and I'd let it go for maybe half a second, then roll back on the throttle to catch it. But it was definitely faster to go through the corner without sliding, because letting off the throttle cost me a lot of speed.

I'm going through my video of the day, but I don't think I got any video of it (camera screwed up).

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Old 08-05-2009, 06:28 PM
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Max Sluiter
 
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The reason it is quicker for rally drivers on slippery surfaces is that they carry more speed into the turn than can normally be sustained in a turn. They pitch the car sideways and use the throttle earlier to drive the car into the apex. The car is pointing sideways towards the curve's instant center so the throttle steers the car, keeping it on the fast racing line. "Steering with the throttle" uses all of the tire's lateral grip and adds some of the tractive force rather than using only the lateral grip. This makes the friction elipse effectively larger.

Oversteer is also a lot of fun, as you now know.
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Old 08-05-2009, 10:51 PM
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There are corners where it's quicker to let the rear step out, and some where it's slower. Being able to rotate the car in a tight corner can be much quicker than not being able to. Countersteering a drift through a sweeper is not going to be faster, as you've discovered.

Generally speaking, quicker track cars are set up with more oversteer than most of us would be comfortable with. But they're not set up that way so the drivers can do Faszination-style hod dogging.
Old 08-06-2009, 08:14 AM
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[QUOTE=Jack Olsen;4820491]There are corners where it's quicker to let the rear step out Being able to rotate the car in a tight corner can be much quicker than not being able to.

Like in 5b @ Mosport!
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Old 08-06-2009, 08:20 AM
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[QUOTE=Paulporsche;4820506]
Quote:
Originally Posted by Jack Olsen View Post
There are corners where it's quicker to let the rear step out Being able to rotate the car in a tight corner can be much quicker than not being able to.

Like in 5b @ Mosport!
I was thinking exactly that, it's the perfect corner to do it, except that the walls are so bloody close there that it's just not worth the risk.

For those unfamiliar with the track, you can see the difference between 3 and 5 on the track map:



or you can watch me drive a lap of it (with no drifting in 3):
http://www.youtube.com/watch?v=EP_DgE1yxgA

Entry to 3 is at 0:37, 5 is at about 1:00.
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Old 08-06-2009, 09:33 AM
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tighter double apex turns or extending a long straightaway...
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Old 08-06-2009, 09:58 AM
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Chris,

Nice lap. Instead of treating 5b as a corner like the others, try straightlining through 5a into b, jabbing the brake, downshifting, giving the wheel a quick flick to the right, and flooring it. This should rotate the car and get you going up the hill w/ the throttle down. If you keep it @ the apex, you shouldn't slide out to the wall.
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Old 08-06-2009, 10:50 AM
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I was trying that later in the day - faster through 5a, then really hard and short on the brakes and a sharper turn into 5b. Didn't really get it right, though. No way I'll be sliding through there anytime soon though - that's where I crashed a few years ago. Once bitten...
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Old 08-06-2009, 11:53 AM
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I hear ya. Having a 911 to drive home @ the end of a track day is a lot more important than any lap time.
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Old 08-06-2009, 12:38 PM
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I don't know why people have so much trouble near turn 4. One event many years ago I'd come through 4 and find someone sideways under the bridge blocking my line. They would go off on the right, over-correct and hit the wall on the left then wind up under the bridge. The second time the only warning I had was seeing the marshall reaching for a flag so I just stayed on the brakes.
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Old 08-06-2009, 08:01 PM
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I've heard several stories of big crashes in 4, but all from "many years ago". I've been driving at Mosport for 4 or years now and have never seen a crash there. I wonder if it might have to do with the repaving for ALMS back in the late 90s - maybe with the wider track it's a less dangerous corner. I certainly really enjoy it. I still brake too much for it, but this week got my braking down to what I would call a "heavy tap". Still not just a weight-transfer tap, and certainly not just a lift, but just a bit of speed correction. For sure less than I ever have before. And the car felt just as stable as always, if not moreso. You really can carry incredible speed through there, all the way to the bottom.
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Old 08-07-2009, 05:26 AM
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There seems to be a tendency to start 4 out too far to the right, almost like 2.
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Old 08-07-2009, 05:36 AM
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The many years ago was probably over 20 years. The events were mostly Zone 1 driver's ed operations. It was really fun to drive Mosport, Watkins Glen and Shannonville. I drove a '73 9141.7 at the time, so it wasn't particularly fast. I do remember talking with some very fast 1.7 drivers, and asked them why they didn't have 2.0 engines; they were quite happy to be the fastest 1.7 drivers around. More about skill, and wringing out maximum performance from what they had rather than trying for the absolute lowest lap times.
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Old 08-07-2009, 07:38 AM
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I understand perfectly well where they're coming from! I've frequently got the choice between my old girl and my dad's 02 996 turbo. I almost always choose my car
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Old 08-07-2009, 08:14 AM
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^ He would be proud.

http://www.youtube.com/watch?v=vSaw5kEjUJ4

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Old 08-07-2009, 09:23 AM
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