what the hell is lift-throttle oversteer?

[stevesnj]

Originally Posted by FRSupra

I just wanted to add to @billwot reference to the SW20's, and I hope this helps explain a little better for the OP.

"other journalists point out that most mid-engine and rear engine sports and super cars exhibit similar behaviour, and that a change to the driver's response to oversteer is really the solution. In any car, braking shifts the weight forward, and acceleration to the rear. When drivers enter a corner with too much speed, and lift the throttle mid-corner, the weight transfers forward causing the rear tires to lose traction (called lift-off oversteer), which can result in a spin. When improper steering inputs were made attempting to correct this non-power-on oversteer, the rear of the MR2 would swing one way, then wildly (and quickly) the other—thus the term "snap" oversteer. Toyota elected to change the MR2 suspension and tires to reduce the likelihood that this would occur, though many drivers would lament the change and claim that it "neutered" the sharp edge the MR2 was known for.[21] Toyota claimed that the changes were made "for drivers whose reflexes were not those of Formula One drivers."

(from Wiki)

This is why I would think to get grippier tires on the rear and keep the stock tires front. And save some money also.

[InspGadgt]

Originally Posted by strat61caster

Bump stops, common in offroad and some forms of racing (I know them from NASCAR).

Problem is that in order to install them effectively on a car you have to have a very good understanding of every possible road condition the car will experience, difficult for a road car. And when you hit them it can be very jarring, even worse for handling in most cases.

Instead you engineer the problem away by giving the suspension geometry 'anti squat' or 'anti dive', this thread seems pretty competent at explaining the specifics:
http://www.pro-touring.com/threads/1...-Squat-Physics

Don't bump stops reduce upward travel of the suspension? Droop is the opposite the downward travel of the suspension.

Anti-dive would do the trick too

[strat61caster]

Originally Posted by InspGadgt

Don't bump stops reduce upward travel of the suspension? Droop is the opposite the downward travel of the suspension.

Anti-dive would do the trick too

Weird, I didn't think to consider it from a suspension standpoint so I guess I misread you comment, yes you're correct and I'm wrong on bump stops.

You could swap to shorter travel suspension I guess but on most street cars downward suspension is almost never close to running out of travel.

[chaoskaze]

It's a good thing in hands of professional. They call it neutral handling? Since they can induce it when they want to and control the car mid corner. However it's obviously a bad thing if u don't know what you are doing.

[stugray]

I guess this is related to, but opposite from "Snap In Oversteer"?

The way I see it is that "Lift-throttle" oversteer is when lifting off the throttle makes the ass go out the same way it was trying to go out (slight oversteer leads to massive oversteer).

"Snap IN Oversteer" is when the ass is trying to go out, and lifting makes the ass come in so quickly that it goes out in the opposite direction.
And rapid, repeated interations of this is what we typically call a "tank slapper"?

Do I have those terms right?

[Sarlacc]

Originally Posted by stugray

"Snap IN Oversteer" is when the ass is trying to go out, and lifting makes the ass come in so quickly that it goes out in the opposite direction.

My old merc was prone to doing that. Not nice. Never knew it had a name.

[InspGadgt]

Originally Posted by strat61caster

Weird, I didn't think to consider it from a suspension standpoint so I guess I misread you comment, yes you're correct and I'm wrong on bump stops.

You could swap to shorter travel suspension I guess but on most street cars downward suspension is almost never close to running out of travel.

That's what I thought but wasn't sure. On RC cars we can change the limits of suspension in both directions usually with just a couple of set screws in the arm for adjustment. By limiting the downward travel of the rear suspension you limit the upward travel of the chassis which is what happens when you brake or decelerate off-throttle. By limiting that movement in the chassis you can limit the weight transfer to the front of the car. Most of the adjustments we can make on the small RC cars are designed out of full size cars before they even get built. Sometimes I think it would be better add these into real cars for the people who like to mod their cars. How much easier would it be to properly lower a car with an adjustable upper camber link and multiple upper camber link mounting positions. You could lower a car to any height and have it keep it's proper camber. Not to mention all the other adjustments we can do on the small scale cars that are not on full sized cars.

[FRSupra]

Originally Posted by stevesnj

And save some money also.

I was surprised when I saw the cost of the Primacy's in comparison to something like the Pilot Super Sports.

[stevesnj]

Originally Posted by FRSupra

I was surprised when I saw the cost of the Primacy's in comparison to something like the Pilot Super Sports.

Yeh, someone I know got one replaced and I just remember being floored when I heard the price. Just want somewhat softer but stock size.

[fistpoint]

It is the reason more than half of the wrecked twins have been wrecked...drivers freaking out in a turn and letting off the gas when they should have kept their foot on it.

I spun my moms Mustang GT 25 years ago by doing this...

[BRZZZZZZZZZZ]

I think lift off oversteer being either a good or bad thing really comes down to driver preference. Some people don't like it because it gives them the sense of the being unsettled and unstable and they may lose confidence, other people like it because it may help them rotate the car into the corner without having to resort to other techniques, or they may be trying to have a little bit of fun.

[emutcfut]

Originally Posted by strat61caster

Weird, I didn't think to consider it from a suspension standpoint so I guess I misread you comment, yes you're correct and I'm wrong on bump stops.

You could swap to shorter travel suspension I guess but on most street cars downward suspension is almost never close to running out of travel.

Droop can be limited using straps except I've never heard them being used on anything other off road trucks.

[totopo]

Originally Posted by InspGadgt

That's what I thought but wasn't sure. On RC cars we can change the limits of suspension in both directions usually with just a couple of set screws in the arm for adjustment. By limiting the downward travel of the rear suspension you limit the upward travel of the chassis which is what happens when you brake or decelerate off-throttle. By limiting that movement in the chassis you can limit the weight transfer to the front of the car. Most of the adjustments we can make on the small RC cars are designed out of full size cars before they even get built. Sometimes I think it would be better add these into real cars for the people who like to mod their cars. How much easier would it be to properly lower a car with an adjustable upper camber link and multiple upper camber link mounting positions. You could lower a car to any height and have it keep it's proper camber. Not to mention all the other adjustments we can do on the small scale cars that are not on full sized cars.

Limiting droop does NOT change weight shift forward or backwards. If you hit the droop limit on one wheel, usually the inside, you get in-lift. If you hit it on both wheels (mind bogglingly retarded) your suspension will basically stop working. It will be like if the wheels were solidly connected to the car. BAD IDEA. It will have shit for traction. Every little bump will upset the entire car. If you did this on the rears, braking would be an exciting process. please don't limit your droop travel on a real car.

Originally Posted by BRZZZZZZZZZZ

I think lift off oversteer being either a good or bad thing really comes down to driver preference. Some people don't like it because it gives them the sense of the being unsettled and unstable and they may lose confidence, other people like it because it may help them rotate the car into the corner without having to resort to other techniques, or they may be trying to have a little bit of fun.

Okay, so I've been waiting for the more experienced drivers to actually come in here, but for some reason everyone is avoiding it. Lift-off oversteer sucks balls. Unless you know what you are doing or are in an empty parking lot, I would highly suggest you don't induce over steer with lift-off. At the track it is very often the cause of spins and causes people to fly off track. When you left off the gas, the weight shifts forward, the springs push the rear suspension up, the camber changes, a lot of stuff happens, and basically you lose traction in the rear and gain it in the front. If you are near the limits already, then you will oversteer.

here is an example of it: (starts at 12:44)
[ame]http://youtu.be/IPQyQgyuNMI?t=12m44s[/ame]

just search you-tube for lift off oversteer, you get tons of examples of amateurs spinning at the track.

[chaoskaze]

Did someone just linked drift bible?! <3<3<3