1993 Turbo MR2 Lift-off Oversteer

First day on a track. Rookie

[clintmc]

As a 1990 MR2 SW20 owner I knew it was coming as soon as I heard the change in engine note on a curve =)

[iliovecaRS]

oh yes the famous snapiness of these cars

[briancorrigan]

The Early SW20 MR2 rear suspension geometry is whacked. Think of it as unintentional rear wheel steering. In addition to the throttle-off weight transfer inherent in every mid or rear engined car - decellerate in a turn and the weight of the engine out back wants to swing the ass-end out into oversteer - the MR2's rear end ALSO changes from toe-in (fully compressed) to toe-out (full droop) signigficantly during its full range of motion. The point is, you get a lot more toe CHANGE for every vertical inch of movement than you do in most other cars.

Once you, our fearless MR2 pilot, take a "set" in a turn, you are dealing with a steady state (slight toe-in) condition on the outside rear wheel. If you momentarily unload that outside rear, the toe-in decreases and you get ...hmm... slight oversteer(?)....no, a better description might be slightly less understeer than what you had a moment ago...LESS toe-in. Still toed-in, but a lot less toe in than a moment ago.

The problem is that when you are carving a turn just below the limit of traction, lift off and the rear weight bias of the car want's to push the tail out and, at the EXACT SAME MOMENT, the outside rear wheel has less toe-in then it did a moment ago. The outside rear wheel, in effect, turns out slightly from where it was pointed a moment ago, joining forces with the outward push of inertia. And that's when traction does a mic drop and all hell breaks loose.

When you lift off mid-turn in an MR2, the combination of weight pushing out AND the rear wheel turning out slightly from where it was pointed before you lifted throttle is what causes the limit of traction to not just be exceeded, but to be suddenly and completely overwhelmed. Snap-oversteer. Now you go to catch it, and the rear end cycles between loading and unloading - neutral toe, to toe-in - and you soon find yourself chasing your tail.

[shanemack]

just so i understand....you let off the throttle at the end of the corner instead of accelerating out of the corner and that caused weight transfer which caused the rear end to fling?

[WhoToldYouThis]

What would've happened if you had quickly pressed on the gas as soon as your car started sliding slightly. Would that have corrected the oversteer?

[mistaanime]

lift off sux, but its okay..you only learn from your mistakes. less lift, and more gas will prevent you from spinning . most of the errors come from miss calculating the course. once you get that down. it'll be smooth sailing there.

[dotty]

this lift off seem iffy to me, your Geometry, bushes, springs/coilovers must have been in bad condition?