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How much wheel lifiting is too much?

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Old 02-10-2012 | 10:52 PM
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Originally Posted by winders
A tire in the air cannot provide any traction. Once a tire is in the air, the axle at the opposite end of the car must deal with all the load transfer. Neither of these is a good thing.

You can't always eliminate wheel lifting, but it is best to eliminate it if you can.

Scott
No doubt that a tire on the ground is better, but the inside front tire is never doing much (especially when accellerating out of the corner).

I've chased this on a few cars. Most times it ends in going slower. One time it ended up with droop limiters and a trip to the wall.
Old 02-10-2012 | 11:00 PM
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Originally Posted by Matt Romanowski
Most times it ends in going slower.


Old 02-10-2012 | 11:20 PM
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I think what Scott is eluding to is the more you commit to entry speed the less you are able to mash the throttle at exit. Inside wheel lift can be exacerbated by not unwinding the wheel and or over slowing and applying heavy throttle on a later apex exit. I remember Leh Keen commenting on someones avatar depicting a ton of wheel lift and he had suggested keeping four wheels on the track as faster. You may not have much grip on an inside wheel but once off the ground you are likely to exceed the grip for the outside wheel.
Old 02-10-2012 | 11:40 PM
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Originally Posted by himself
Question for the set-up gurus: how much lifting is too much?
This is too much. Anything less than this is a great forum post, great photo, or adrenaline rush. Your paycheck doesn't depend on it, so throw that wheel in the air like you just don't care.

Old 02-10-2012 | 11:41 PM
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Originally Posted by bobt993
I think what Scott is eluding to is the more you commit to entry speed the less you are able to mash the throttle at exit. Inside wheel lift can be exacerbated by not unwinding the wheel and or over slowing and applying heavy throttle on a later apex exit. I remember Leh Keen commenting on someones avatar depicting a ton of wheel lift and he had suggested keeping four wheels on the track as faster. You may not have much grip on an inside wheel but once off the ground you are likely to exceed the grip for the outside wheel.
Answer your doggone email!
Old 02-11-2012 | 12:29 AM
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Originally Posted by Veloce Raptor
TD, why do you ask? What is the car doing when this happens? How does it feel? Is it rolling at turn in or flat?
Car is actually pretty set and transition to power is not really hampered. Of course, we're all working on picking up the throttle a little earlier, but for the most part I'm not waiting on the car.

Don't poo-poo my craptastic driving in this video. It's been a long time since I was on the track, without a passenger, and driving this configuration. (This was Saturday, session 2).

Best laps of the weekend were in the 1:22s, but I'm pretty sure I could creep into the 1:21s if I uncorked a flyer and didn't drove so poorly.




-td



Originally Posted by Veloce Raptor
BTW, the flying cone is awesome. Your doing?
Was the guy behind me! I dig the picture



Originally Posted by Astroman
OT, but is your entire car wrapped in that carbon vinyl (as seen in your avatar)? It looks cool! What is the original color of your car?
Full carbon wrap. Car is silver.

Last edited by himself; 02-11-2012 at 01:12 AM.
Old 02-11-2012 | 01:12 AM
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Originally Posted by bobt993
I think what Scott is eluding to is the more you commit to entry speed the less you are able to mash the throttle at exit. Inside wheel lift can be exacerbated by not unwinding the wheel and or over slowing and applying heavy throttle on a later apex exit. I remember Leh Keen commenting on someones avatar depicting a ton of wheel lift and he had suggested keeping four wheels on the track as faster. You may not have much grip on an inside wheel but once off the ground you are likely to exceed the grip for the outside wheel.
Like everything else, it all depends. Which corner, which car, which driving style. The photo below of the Atlantic was setting a lap record.
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Old 02-11-2012 | 01:17 AM
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Matt,

You can find all the photos you want showing a front inside tire in the air. That doesn't make it a setup we should strive to copy. Sometimes it is what you end up with....but it is not what you want if you can help it.

Scott
Old 02-11-2012 | 01:24 AM
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Originally Posted by winders
Matt,

You can find all the photos you want showing a front inside tire in the air. That doesn't make it a setup we should strive to copy. Sometimes it is what you end up with....but it is not what you want if you can help it.

Scott
I'm not saying you should copy it or strive for it. Depending on the car, corner, etc., it may happen. Doesn't really mean anything. Trying to solve it all the time is answering the question that no one asked and will probably make you slower. I've been down that road and know where it ends.
Old 02-11-2012 | 01:26 AM
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Originally Posted by dotframe
i have no idea but those are awesome pics either way
Photog got some good ones. Here are a few of the other pics I'm digging











Old 02-11-2012 | 01:32 AM
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Interesting read:

http://www.morsemeasurements.com/store.asp?pid=34053

Scott
Old 02-11-2012 | 02:40 AM
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^^ the pictures in that article typically show big variation in inside wheel lift front to rear which is obviously symptomatic of the problem the article is addressing, that ideally a car will always corner better with 4 wheels on the ground than 3. If you are getting a large amount of wheel lift at one end of the car compared to the other, it probably indicates room for improvement, but in the case of the OPs pictures that's not the case.

The rear wheel is also lifting a little, plus the corner is dropping away on the left hand side and presumably he is going to power at that point transferring more weight rearward. All adds up to a pretty normal looking picture to me and I wouldn't be worried about it indicating a setup problem unless something felt bad with the car.



With enough tire grip, most road cars with relatively high centre of gravity and suspension design limitations, even the most perfectly setup car, will reach a point where they will lift inside wheels. If you had enough grip they could eventually roll over. As long as there isn't a big imbalance between front and rear in the amount of wheel lift, it may just indicate you are reaching the physical limits of cornering force for that particular setup.

Old 02-11-2012 | 08:37 AM
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how is your turn in?
Old 02-11-2012 | 08:51 AM
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TD, based on the video (alone), I'd say leave the car alone & smooth out the driving. I am curious also how turn-in is.

FYI, there are a couple of 1:23's with a passenger in here from November 2010 on that clockwise configuration:


Last edited by Veloce Raptor; 02-11-2012 at 09:08 AM.
Old 02-11-2012 | 09:23 AM
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Any pics sans the instructor?


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