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"floating sensation" while turning

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Old Jan 16, 2009 | 07:51 AM
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"floating sensation" while turning

At an autocross last year, at the TMS Bus Lot (so sealed asphalt), I was riding along with Evo_Someday (VIII). One section of the course was a 180* turn. When we took this turn, there was this floating sensation and the car turned *beautifully* and effortlessly and really allowed him to put the power down coming out of it (but I think it surprised him because other than that 1 second sensation, the run wasn't anything special).

A couple days ago, I was taking a corner a bit too fast and the ASC (traction control) kicked in and caused the engine to cut. I felt a 1/2 second of this same floating sensation (as the rear came around like a RWD car).

In my case, this felt like throttle lift (errrr cut?) oversteer. I'm not sure exactly what Evo_Someday did to make his car rotate (maybe he can remember and chine in).

Is this the sensation that I should be looking for when making corners? Does it imply that I'm rotating the car better? If so, what sort of techniques help you achieve this balance (other than slow in fast out )?

It definitely is a "magical time" like in the movies when they slow everything down, but I feel that there's a knife edge there where too much can be a bad thing.

It definitely felt better than just trying to plow the car around the corner for sure.
Old Jan 16, 2009 | 08:50 AM
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Here is an example of it

http://www.youtube.com/watch?v=Hsbk3vBMMow

In most cars it's a HUGE no no (especially Porsches), but in the Evo you can usually get away with it and help turn in. I would try to stay away from throttle lift oversteer, there are safer ways to get the car to turn in (suspension setup/entry speed/proper line/etc.)
Old Jan 16, 2009 | 09:19 AM
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I know that TLOS is a bad thing (there's a video of a Porsche hitting a tire wall here at MSR because of it). I watched a few FWD cars at an HPDE go off right in front of me because they lifted in a sweeper.

I'm just describing the sensation as being the same. Maybe Evo_Someday did a "controlled" TLOS and that's why the sensation was the same?

At the same autocross (or one at the same place), I put down a great time, but never felt the same lightness through corners.

I've been trying to recreate the feeling I did have though. I was hitting the turns in a very satisfying manner, at a much higher speed than I thought possible [I could have SWORN I was going to hit a cone in this one corner, but apparently I wiggled the car through it each and every time]... must have just had the car setup decently and been in the zone or something.

Here's the Porsche video:
http://www.youtube.com/watch?v=b5XNUSMstMQ (go to the end, and the watch the language)

Here's a different one:
http://www.youtube.com/watch?v=rY2Ie7_aUtg
Oh wow... the guy that crashed deserved to. I've not done the 3.1 (nor have I done it in a Porsche, but he was all over the wrong lines on the 1.7 portion... yowzers.

Last edited by goofygrin; Jan 16, 2009 at 09:40 AM.
Old Jan 16, 2009 | 09:50 AM
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It looks like you want us to assume it's not in the setup since you state the rest of the run was not as memorable.

Do you know if he operates the brake with his left foot?
Did he shift late/post entry?
Does he ever Scand flick?
Old Jan 16, 2009 | 10:04 AM
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That floating feeling you are talking about is commonly called "rotation" and can be usefull tool when predictable (do not confuse with snap oversteer wich is mostly unpredictable, dangerous and hard to control)

Rotation is usually achieved with throttle lift or trailbraking, most competitive autocross cars are set up to rotate nicely under the two condition(TLO, TB), the result is the rear end getting light and rotating just enough to give you a more favorable angle pointing at the exit, allowing you to use less steering and get on the throttle earlier/harder. Road racing cars tend to be set tighter as TLO can be scarry at high speed and do not inspire driver confidence but a little TB rotation is still nice on the road course.
Old Jan 16, 2009 | 10:07 AM
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I get that way after a six pack or so. it's pretty normal.
Old Jan 16, 2009 | 10:10 AM
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Were the cars on street tires?

I think street tires feel like sponges in general, and that the car floats around without a positive hold on the tarmac. Whereas race tires have a much more connected feel to the tarmac.

I think what your talking about is flirting with absolute loss of traction, and the floating is simply the g- force dropping off as the car looses traction. Most good street tires have a good transition at this point, which is why driving them near the limit creates the spongy floating feel.

Race tires offer much more bite, and then typically give away more dramatically. That's why it's good to learn were the line/limit is with streets tires first.

I also agree that at Auto-X speed you can use lift/braking to rotate the car controllably. but at road course speed you need the car tighter.

Last edited by jid2; Jan 16, 2009 at 10:13 AM.
Old Jan 16, 2009 | 10:30 AM
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Originally Posted by jid2
Were the cars on street tires?

I think street tires feel like sponges in general, and that the car floats around without a positive hold on the tarmac. Whereas race tires have a much more connected feel to the tarmac.

I think what your talking about is flirting with absolute loss of traction, and the floating is simply the g- force dropping off as the car looses traction. Most good street tires have a good transition at this point, which is why driving them near the limit creates the spongy floating feel.

Race tires offer much more bite, and then typically give away more dramatically. That's why it's good to learn were the line/limit is with streets tires first.

I also agree that at Auto-X speed you can use lift/braking to rotate the car controllably. but at road course speed you need the car tighter.
+1 on the tire issue. Street tires have a more linear loss of traction, so it is easier to predict and drive at the limit. R compounds, and to a greater extent, slicks do not loose much traction at all until the moment when you loose adhesion completely and, then it's too late and you've spun. Driving at the limit on street tires is a freakin' BLAST!!! If you are interested, the next track day I'll give you a ride and you can get that feeling the whole way around the track...

As far as rotating the car, I noticed that just the stage one uograde that I did a couple years ago did wonders for powering out of an apex and making the car feel more like a RWD car. Now the car can swing the rear out at will.
Old Jan 16, 2009 | 10:52 AM
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This was on street tires and Evo_Someday does LFB. I'm not sure if he did in this case or not (or if he'll even remember).

It looks like you want us to assume it's not in the setup since you state the rest of the run was not as memorable.
Well, it's a stock suspension Evo VIII with the front camber ~-2* and around 0 toe. My car is much more planted and much more aggressive suspension wise, so I will likely have a harder time getting this "loose" feeling.


Rotation is usually achieved with throttle lift or trailbraking, most competitive autocross cars are set up to rotate nicely under the two condition(TLO, TB), the result is the rear end getting light and rotating just enough to give you a more favorable angle pointing at the exit, allowing you to use less steering and get on the throttle earlier/harder. Road racing cars tend to be set tighter as TLO can be scarry at high speed and do not inspire driver confidence but a little TB rotation is still nice on the road course.
So it sounds like, in your opinion, that a little of this, for autocross, can be desirable -- as long as you can control it. On the road course, likely not so much.
Old Jan 16, 2009 | 10:54 AM
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Originally Posted by TxEvo8
+1 on the tire issue. Street tires have a more linear loss of traction, so it is easier to predict and drive at the limit. R compounds, and to a greater extent, slicks do not loose much traction at all until the moment when you loose adhesion completely and, then it's too late and you've spun. Driving at the limit on street tires is a freakin' BLAST!!! If you are interested, the next track day I'll give you a ride and you can get that feeling the whole way around the track...

As far as rotating the car, I noticed that just the stage one uograde that I did a couple years ago did wonders for powering out of an apex and making the car feel more like a RWD car. Now the car can swing the rear out at will.
No need to scare me on the track. I put the Star Specs through the limit of cohesion (or close enough to it for me) the last time I was at MSR. Tim's on video telling me that that was the limit of street tires (but what's funny is it was the limit for the poor line I took -- I reviewed the tape and a couple laps later I carried more speed on a better line).
Old Jan 16, 2009 | 11:38 AM
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^^^^ You should buy Ryan's (Blacktrack) KW coilovers. You seem to be one of the few EVO X guys hitting the track. He's had them for sale a while now. Best deal on legit track suspension for a X for sure.
Old Jan 16, 2009 | 11:49 AM
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I have good-enough-for-me coilovers and don't have the money to spend on replacements. Honestly there are people doing more track time in their X than me (Robevo for one). I just like to jabber about it lol.
Old Jan 16, 2009 | 01:22 PM
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Find some video of Mark Daddio in his SM car. Or any of the nationally competitive SM or BSP cars. They have TONS of rotation on corner entry, until you plant the throttle, at which point they grab and GO. I've driven a second gen MR2 that did the same thing. It would start to rotate, and as soon as it was pointed where you want it to go, floor the throttle, the rear tires would grab and it would shoot you out of the turn. Beautiful when it's done right.
Old Jan 16, 2009 | 02:43 PM
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Practice makes perfect. You found out how to do it, now you just need to practice. Be prepared to spin at an autocross now. LOL You will learn to control the trail braking, and learn to get out of it. Also, you will learn that the more traction there is, the more aggressive you have to be to get the car to rotate.

Speeking of which, only practice this at an autocross.
Old Jan 16, 2009 | 04:03 PM
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Originally Posted by goofygrin
My car is much more planted and much more aggressive suspension wise, so I will likely have a harder time getting this "loose" feeling.
Actually, the opposite is true. The car should be more responsive and therefore be more twitchy at the limit as roll stiffness increases, all things being equal. If anything, it should be a million times easier to get a car with 14k rates all around (IIRC) to rotate compared to one with springs as pathetically soft as a stock Evo's.

Originally Posted by goofygrin
So it sounds like, in your opinion, that a little of this, for autocross, can be desirable -- as long as you can control it. On the road course, likely not so much.
IMO, on a front-heavy AWD car like the Evo, you need as much rotation as you can get out of the car, get comfortable driving it that way, and then make it rotate a little more. How you go about doing this also depends on other factors, particularly your tires and diffs.

Once you get the car set up right, it can be stupid easy to drive fast - Daddio is one of those who pretty much has it down. He has a pretty much unreal rhythm of lift - steer - rotate - power that he does extremely smoothly and quickly. I'm amazed at how quickly he can get that car can change direction.

http://www.youtube.com/watch?v=Mjd2bUI71KU (see the white RS)



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