Several times I have been going through an autocross course swinging the back around and when the car regains grip it jerks back. "Jerk" is actually a little to mild for what happens. It is more of a whipping effect. My dad smacked his head on the plastic trim above the door one time and it was very loud. Fortunately, he had his helmet on but it was a very loud crack sound.

My question is...
Why does my car do this?
Is there a way to reduce this jerking effect?
Does my car just hate me?

My car is completely stock if that makes a difference in your response.

 

Beyond the obvious drive smoother?

What are you doing when it jerks? Are the rear tires spinning, then when you get traction, it snaps itself back in line? I guess i am a little unclear on what you are describing.

 

Driving smoother would be the obvious answer but I want to have fun too.

I get on the gas coming out of a turn, the back tires start spinning, the car starts going sideways (back tires still spinning), I turn the wheel to keep it from swinging around (back tires still spinning), I let off the gas to get the car straight for the next turn (tires no longer spinning), and the car (as you say) snaps straight with violent force.

 

i would say stop touching yourself

 

That is how it works. The key is to have the car straight when you back off the throttle. The car wants to be inline, the rear tires want to follow the fronts. As soon as you give the car traction, if it is out of line, the rear will try to get back in line. So, really, the key is, learn how to keep on the power coming out of a corner, and smoothly transision to forward traction, without letting it tank-slap.

Just as I have said in many other postings. Tighten up the nut behind the wheel.

 

 

I was going to say cold showers but that works just as well

 

You really are just overdriving the car. The car has alot of chassis movement in the stock form. Basically, the best way iIcan describe whats happening is ever see a car fishtail left then right then spin out to the left? Thats basically what you are doing and getting a snap recovery to the oposite side. Your polar movement and tire slipage are way too abrupt that they yaw until polar thrust reduces and bites, then it snaps back force in the opposite direction hence why your heads are slapping around.

 

So it wont help if I buy better suspension parts... just dont drive as fast out of corners?

If I buy the koni yellows and thicker sway bars and such will it be less common?

Would I feel a difference if I swapped my stock LCA and Panhard bar for a tubular set up? I mean would it get stiffer?

 

It would indeed help buying performance parts. The more built the car is the easier it is to drive. A factory car has much slop in the shock damper, the bushings, tires, chassis flex, etc etc. The more you reduce slop, the less enertia that keeps wanting to travel further when ther tires grip but the chassis keeps going. if the enertia rolls it over enough and the bushing slop allows entertia to colapse the bushing enough, all these eventually hit a brick weall and then suddenly snap intoithe jerking motion you decribe. Reduce the slop, reduce the build up and then brick wall hit of the suspension.



Edit: Analogies are so hard to come up with in trying to describe senerios. You go and repeat this so called Brick wall effect I just came up with and people will think 'what?' It is basically called snap oversteer to be technical where the suspension points and chassis do not give anymore and the enertia of the body roll still takes the polar enertia through it and exceeds the grip of the tires once the suspesnion hits the so called brick wall. I know what I wrote, but I just lost myself in that last long sentence.


Now when this enertia finally comes to to regain tire grip, it winds up again and unloads back the other way. Thats how this problem hampers both turn in and trasition cornering.

 

Lets go to the next step.


You have now built your car extremely radical with a very stiff setup. It now has absolutely no give at all and at the first bump, it losses traction because it bounces right over the bumpo and slides a bit until regaining grip- this is bad also and hard to drive. It might be predictable, predictable in a way that you expect it to just slide in every corner and you are ready for it, but it is not optimum fast as you are loosing traction.


So We discover a little roll is good-why?- Because it gives a bit of roll over to a point where you can feel a bit of sway and reference just how much the car is pressed before it hits rock solid (the brick wall) and slipps laterally.


The golden question- How much body roll is good? That my friend depends on the driver and his likings and conditioning. THe softer the suspension the better the mechanical grip until dyanmic lateral loading comes into play and unsettles the tire contat patch. Depends on the track, the driver, the surface temps and condition that day, and the overall conditioning of the driver to maintain accuracy during the duration of that giving situation (aka race length). It is easier to get fatigued and make a mistake with a softer suspension. It is easier to overheat on particular tire of the four with a firmer setup and/or lift a tire-----So many give and takes. Thats why it boils down to drivers style and liking.

The absolutely best quote you will ever here me say is,"You will not be fast until you learn to drive with the brake pedal". Trailbrake- learn it, live it, control the chassis with the brake pedal.


I talk alot about suspensions, my real expertise is actually driving. I learned suspemnsions as a biproduct of refining that skill.

 

i would have to say that u all are losers (except for Fyrstorm)for getting so in depth on the car (JERKING).how about he doesnt know how to drive their car. just end this stupid thread!!

 

The problem is you are letting off the gas, the only way to keep the car from jerking is stay in the gas and keep counter steering like you are doing and the car will straighten itself back out. Suspension has nothing to do with it, the only thing high dollar suspension mods. will do is maybe soften the jolt but the jolt is still going to be there.

 

My name is Jimmy and i am a jerk. I add nothing constructive.

 

You know, contrary to your belief, spinning your tires is NOT the fastest way to travel in a strait line, or around a turn for that matter. You need to learn throttle control. It is very possible for you to accelerate quicker at 75% throttle rather than 100% throttle.

Your first problem is you are getting the car sideways. Second problem is you are suddenly letting off the gas. You need to do everything gradually. By immediately letting off the gas you are upsetting the balance of the car and the car wants to follow a new path now. Dewey was every bit correct in his post.

 

I never said spinning my tires was the fastest, I only said it was "fun". I understand that by spinning the tires I will be going slower due to the lack of traction and that it is possible to go faster at 75% throttle because of not spinning and spinning at 100% issue.

As for the first problem you stated... that isnt a problem, I wanted the car sideways. Its FUN! (If you think drifting a vehicle isn't fun in even the slightest way, there must be something seriously wrong with you)

The car is fairly new to me and I am still getting used to the very sensitive gas pedal. I've never drove a car that is so sensitive. The slightest movemment of my foot plants me in the seat, its really odd.
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As for all the idiots out there that like to make things dirty, grow up. If you dont have anything constuctive to say dont say it.
Thank you to everyone else that helped answer my question.