Name that handling phenomenon

RockSnake · #1 (**permalink**) 10-30-2003, 05:33 PM

Today, as I was accelerating through a sweeping curve, a truck stopped in front of me. When I let-off the gas, the car 'twitched' as if trying to oversteer. I haven't experienced this before, although I have long thought my rear springs were too stiff.

I tried to force this reaction on other streets...with the same results. I guess I've always just continued accelerating until straightening-out.

Anyway, I figure there is a name and a solution for this (besides driving more conservatively). So I welcome any information by those more educated than me.

FYI - I don't have any anti-sway-bars on the car.

392cobra · #2 (**permalink**) 10-30-2003, 05:43 PM

It's called Trailing Throttle Oversteer.

From Panoz Racing School-

" A handling tendency that results in an oversteer condition caused by abrupt lifting off the throttle while cornering, and thus abruptly tranferring weight to the front of the car."

Easing back into the throttle will move the weight to the back.

Be carefull.

jayscobras · #3 (**permalink**) 10-30-2003, 06:04 PM

THAT "UPSETS" THE CAR...KINDA LIKE IF YOU ARE FURIOUSLY MAKING LOVE AND YOU SUDDENLY SLOW DOWN, IT "UPSETS" YOUR PARTNER

OH BY THE WAY, "SLOW IN-FAST OUT" ALSO MIGHT UPSET YOUR PARTNER IF YOU ARE MAKING LOVE

JAY

kountzecobra · #4 (**permalink**) 10-30-2003, 06:35 PM

Jay, since when did any of us care what our "partner" thinks?

mr0077 · #5 (**permalink**) 10-30-2003, 06:36 PM

Something to consider if it was a "twitch" only (and a feeling of looseness or vaugeness in the rear end) is the possibility of a loose bushing, bracket, etc. in the locating linkage for the rear end...might be worth a check.

KobraKarl · #6 (**permalink**) 10-30-2003, 07:02 PM

Good call, 0077,

Loose components in an IRS rear end can take you from toe-in to toe-out in a split second ,...and it feels very weird!.....I would think you would have noticed that on the straight away as well though.

Trail-throttle over steer almost "ditched " me once right after i got my car........scared the crap out of me.

KK

wizard · #7 (**permalink**) 10-30-2003, 07:54 PM

Been There. Done That. Got the soiled undies to prove it.

casaleenie · #8 (**permalink**) 10-30-2003, 08:00 PM

WIZARD,
Post those words of wisdom on the thread by Edley in the lounge..
Definitely words to live by....

wizard · #9 (**permalink**) 10-30-2003, 08:03 PM

Cas

Please Clarify

Wiz

wizard · #10 (**permalink**) 10-30-2003, 08:12 PM

Cas

I got it. Excellent topic.

Why doesn't that thread come on the home page after a new post? I haven't seen it before.

Wiz

Cobra #42 · #11 (**permalink**) 10-30-2003, 08:34 PM

Good Job Fred, You were paying attention in class, you didn't learn that at drivers dull edge event. Inside joke, LOL, db

John A. Simpson · #12 (**permalink**) 10-30-2003, 11:14 PM

If its not severe it can be used to tighten your line slightly, if you are a little too fast into a corner. If you don't expect it or it is great you can end up with a nickname like mine.

Excaliber · #13 (**permalink**) 10-31-2003, 01:21 AM

And often the reason you see the "spin outs" in an SCCA event. Lifting abruptly for the next cone.

My solution is simple, thats why they call me "Cone Killer".

Ernie

coyled · #14 (**permalink**) 10-31-2003, 08:47 AM

Rocksnake, Does it have an IRS? If so, check the toe in. I run more toe in then most, 3/16 in. It seems to settle the rear and make it less twitchy. Also, generally, if you jump into or out of the throttle in a cobra in a corner, you can get oversteer. If its too stiff of a spring rate, it should step out under acceleration as well as when you lift. Good luck, scott.

RockSnake · #15 (**permalink**) 10-31-2003, 09:12 AM

Thanks for the information. I checked the control-arms, and everything appears to be tight. This is an 8.8 'live axle', and yes, it did scare the crap out of me. Sufficit to say, I was not conforming to the posted speed-limit.