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minimizing lift throttle oversteer with driving style change

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Old May 27, 2013 | 08:24 AM
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Default minimizing lift throttle oversteer with driving style change

I suspect the rear being so sensitive to throttle is not entirely due to that year's very stiff rear bar, or rear toe change during suspension travel.

I think it is due to the larger than usual engine drag in this high revving car forcing the rear tires to deal with too much longitudinal acceleration while it's also dealing with a substantial amount of lateral acceleration.

I say that because the longitudinal acceleration (either positive or negative) I apply via throttle input is nowhere near enough to change the rear tire's camber or toe, but because it also causes the tire to have to deal with that longitudinal acceleration, the slip angle changes.

It was fun though, to drive a car that's so sensitive to longitudinal acceleration in the rear.

Note that on my first drive, I rarely used the brakes at all, and so engine drag is doing all the slowing down, thus exaggerating this effect.

Remember what Michael Schumacher does: he never downshifts one gear at a time when approaching corners. He just keeps the car in the high gear he used on the approaching straight all through braking, and then downshifts to the gear he wants to exit the curve with via just one blip.

To test out the theory on my next drive, I plan to approach a curve with the clutch disengaged and use brakes to slow down the car only, to see if I can reduce movement in the rear and make the whole corner feel more linear in this car. Using brakes will spread out longitudinal acceleration to all four tires compared to using engine drag only.

I did both directions of the Ortega highway last night, and got a very good feel for the original MY 2000 car's driving dynamics. I have new S-02 tires, OEM wheels, OEM springs/dampers that are almost new thanks to s2ka's "new old stock", and OEM bars. This is zentrose's old race car that I bought recently, so it is much lighter than stock. The only engine mod is AC delete and CAI. I only had a race seat with no passenger seat. Interior is mostly gutted except for the addition of a steel roll cage, and that piece is heavy. The alignment was done by Clark's House of Suspension. The ride height on all four corners is thus slightly higher than stock, and that probably exaggerates lift throttle oversteer even more.
Old May 27, 2013 | 08:57 AM
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Do not kick the car out of gear. You need to keep weight on the rear end with the car in gear; otherwise you will spin out quite easily. And you're not driving an F1 car either..

Edit: with your configerations I would try this at the lower speed corners near the county line. But stay off the Ortega during holiday weekends. Tons of drunks go to that bar near Elsinore.
Old May 27, 2013 | 10:45 AM
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I think keeping the car in gear upon corner entry merely increases longitudinal acceleration on the rear wheels compared to using brakes alone to slow down the car. Keeping the car in gear does not put weight on the rear end.

I ran with Rockstar Garage's plastic roof, so the aero was good. On the next drive, I'll add back the rear wing. It is loud in the cockpit!

Upon corner entry, do things in this order: push in clutch, apply brakes, select exit gear, near apex of corner apply throttle, and then release clutch. This minimizes longitudinal acceleration on the rear tires.

Alignment settings dialed in by Clark's:

Code:
Front Left  Camber -0.6 deg.
Front Right Camber -0.7 deg.
Front Left  Caster +6.2 deg.
Front Right Caster +6.5 deg.
Total Front Toe     0.0 mm

Rear  Left  Camber -1.3 deg.
Rear  Right Camber -1.4 deg.
Total Rear  Toe     6.0 mm
Wheel Alignment info
Old May 27, 2013 | 12:46 PM
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Originally Posted by myhui
I think keeping the car in gear upon corner entry merely increases longitudinal acceleration on the rear wheels compared to using brakes alone to slow down the car. Keeping the car in gear does not put weight on the rear end.

I ran with Rockstar Garage's plastic roof, so the aero was good. On the next drive, I'll add back the rear wing. It is loud in the cockpit!

Upon corner entry, do things in this order: push in clutch, apply brakes, select exit gear, near apex of corner apply throttle, and then release clutch. This minimizes longitudinal acceleration on the rear tires.

Alignment settings dialed in by Clark's:

Code:
Front Left  Camber -0.6 deg.
Front Right Camber -0.7 deg.
Front Left  Caster +6.2 deg.
Front Right Caster +6.5 deg.
Total Front Toe     0.0 mm

Rear  Left  Camber -1.3 deg.
Rear  Right Camber -1.4 deg.
Total Rear  Toe     6.0 mm
Wheel Alignment info
PM me when you have a chance. I have a record of times on the Ortega. We can do a run if you'd like.
Old May 27, 2013 | 01:24 PM
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Originally Posted by BlakeKleinCalabrese
PM me when you have a chance. I have a record of times on the Ortega. We can do a run if you'd like.
Let me get to know the car and the road better first. I am a new owner, and I am still in the process of sorting out the car. It has numerous ailments. It is not ready for Show Time yet.
Old May 27, 2013 | 03:33 PM
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i think you need to drive the car on a race track and get some instruction.

http://www.youtube.com/watch?v=A2YMwd-NUvk

just like ALL race car drivers, schumi down shifts into the turn (while braking) so that he can use the throttle to transfer car weight in the run for max grip and control as well as acceleration out of the turns. what you 're talking about is rather insane
Old May 27, 2013 | 04:08 PM
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You wanna learn to drive your car hard, get on track with an instructor. This sentence right here tells me you don't know what you're doing...

Originally Posted by myhui
Upon corner entry, do things in this order: push in clutch, apply brakes, select exit gear, near apex of corner apply throttle, and then release clutch. This minimizes longitudinal acceleration on the rear tires.
You should be doing like all that shit at the same time. As your breaking, clutch is going in while also revving the car up and downshifting, and repeating tiill you're in the correct gear, then turning in and accelerating through the turn. For the most part your foot should never be touching the brake once you initiate the turn (trail braking).

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Old May 27, 2013 | 04:38 PM
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Learn to heel and toe.
Old May 27, 2013 | 04:46 PM
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Originally Posted by chadsmith20
Learn to heel and toe.
Exactly. Thank you.

I spent 300 words trying to get to my point, and still couldn't.

You did it in 5.

My point, guys, (and I just tried this while driving someone else's very expensive car without incident) is to let the rear tires do the least work possible.

Why have it rev up the engine when it does not need to do that? The front versus rear brake balance is carefully tuned by Honda. Take advantage of it. The engine should only be used to push the car forward.
Old May 27, 2013 | 04:54 PM
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Not sure if trolling...



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