top speed wobbles

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my car, the Mercedes CLK GTR Race Car, starts to shake a lot when it is going at about 270mph. Is this slowing it down? I got it to go 300mph and is there any way to make it go faster?
 
happyperson
my car, the Mercedes CLK GTR Race Car, starts to shake a lot when it is going at about 270mph. Is this slowing it down? I got it to go 300mph and is there any way to make it go faster?


Might be you have some camber/toe issues that kick in at high speeds? Or it could be the bound/rebound settings get out of range as the speed when you encounter unevenness in the road increase beyond their capabilities? That would, I imagine, reduce or even negate the effect of your suspension, making the car 'jump' or bump-steer.

It is possible there is some limitations as to how fast a car will go. Their aerodynamics and such I mean. I don't know how fast 300 mph is in kph, but I got my Merc up to some 400 kph. That was not a big problem though, so I recon higher speeds is obtainable.

Stian
 
happyperson
my car, the Mercedes CLK GTR Race Car, starts to shake a lot when it is going at about 270mph. Is this slowing it down? I got it to go 300mph and is there any way to make it go faster?

I was surprised to get 255 on Sarth II with full downforce. Zero the DF and I'm sure it will do 270 on the Test Course. Add NOS and there's your 300.

Its faster than you'd expect.
 
Do you have a lot of miles on it?
I noticed the Black LM's from the used lots having high miles need the chassis refreshed to get rid of the high speed wobble.
After a couple of endurances my Minolta began to wobble and I found it also needed the chassis refreshed.
 
Stian
Might be you have some camber/toe issues that kick in at high speeds? Or it could be the bound/rebound settings get out of range as the speed when you encounter unevenness in the road increase beyond their capabilities? That would, I imagine, reduce or even negate the effect of your suspension, making the car 'jump' or bump-steer.
Stian

How should I fix the camber/toe or bound/rebound settings? Does it also matter that I lowered the ride height all the way and stiffened the springs completely?
 
jparker_1987
Do you have a lot of miles on it?
I noticed the Black LM's from the used lots having high miles need the chassis refreshed to get rid of the high speed wobble.
After a couple of endurances my Minolta began to wobble and I found it also needed the chassis refreshed.
I have around 1000 miles on it, but I did do the refreshment plan.
 
Another thing is that the car goes to 300mph, then back to 299mph, then back to 300mph, then back to 299mph, etc. Can someone help me on making it not do this?
 
happyperson
How should I fix the camber/toe or bound/rebound settings? Does it also matter that I lowered the ride height all the way and stiffened the springs completely?

Yeah, I would loosen the springs, and heighten the car. I'll give you the setup I have on it right now. I tried it at Le Mans 2 (no chicanes) just now and it's not too shabby.

Springs 12,5 14,5
Height 60 60
Damper bounce 7 7
Damper rebound 9 9
Camber 2,5 1,5
Toe -1 +2
Stabiliser 4 5

Try it out and see if that helps. Tweak and test and tweak some more, until you have a ride you like.

Stian
 
happyperson
Another thing is that the car goes to 300mph, then back to 299mph, then back to 300mph, then back to 299mph, etc. Can someone help me on making it not do this?

This is probably due to the transmission, you need to make the gear ratios wider and this should push up the speed a little. Dont push it too far or you will lose acceleration at high speeds so fine tuning of the final gear is in order.
 
happyperson
Another thing is that the car goes to 300mph, then back to 299mph, then back to 300mph, then back to 299mph, etc. Can someone help me on making it not do this?
its 1 mph. not a big deal. live with it
 
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