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Old 10-23-2007, 01:42 PM   #1
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Default Setup Questions...

Hello

I have some Question about some Settings (Setup).

I drive an Scythe, and it's a very nice Car ... Nice to Drive, good Balance and fast xD

OK, if i Look at the Setup Theory, a higher Rollcenter (More Shims under Susp. Mounts) have more Cornering Speed and a lower Rollcenter have less Cornering Speed.

I tested last Friday some Rollcenter Settings, and my Feeling was that a Lower Rollcenter means a bit lower Grip and more Cornering Speed, the Car feels smoother, too ... easier to drive.

have someone an Idea? ... I gonna be crazy xD

Thanks
iZzy
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Old 10-24-2007, 09:45 AM   #2
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Nobody have an idea?
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Old 10-24-2007, 10:18 AM   #3
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Higher roll center, meaning your car's roll center is further away from your center of gravity (CG) will cause the car to roll less, transferring less weight to the outside wheel and making the outside tires generate less grip. If the traction of the race surface can support this, you should be able to roll faster through a corner. But if the traction is low it will just make a car harder to generate traction and tend to push or loose rear traction.

The reason for this is traction generated is also power lost. If you're car is generating too much traction you will scrub speed. In a perfect setup you really only want to generate as much traction as you possibly need so you aren't losing speed to friction. A car that is super stuck to the track can end up being super slow through the corners.

You can compensate for that by running lighter springs however, so you end up with a car that does not roll as much but still can generate traction because of the softer suspension spring.

With a T2 my basic setup for "fast" has always been high roll centers, and a softer spring when running rubber tires. Car carries more corner speed and transitions quickly. Even if the traction is super low I can usually compensate by going to a softer spring before I have to change the roll center..

The less the body rolls in general the better the car's transition from left to right will be also, so a high roll center is good for very tight tracks or those with a lot of chicanes since there isn't the time lost from the chassis swaying back and forth and settling.
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Old 10-24-2007, 10:30 AM   #4
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Originally Posted by Desolas View Post
so a high roll center is good for very tight tracks or those with a lot of chicanes since there isn't the time lost from the chassis swaying back and forth and settling.
What is a good size to raise the roll center?

2 mm ? 4 mm ?
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Old 10-24-2007, 10:34 AM   #5
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That depends entirely on the car, track, and the way you drive. You don't always want to raise the roll center.
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Old 10-24-2007, 11:33 AM   #6
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HI Desolas !

Is a Higher RC not Closer on the CG? (Like in the Setup Books).

But, Thanks for the Answer

You posted the Theory, and I think I understand the Theory ... but if I tested this real on the Track (No Theory), a Lower RC .. OK, it has more leverage ... like the Theory, but the Crazy Thing is, this has more Cornering Speed on my Car O.o ...

And that's my Question, why I have this Problem? xD
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Old 10-24-2007, 01:31 PM   #7
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If your car is generating more corner speed with a low roll center than a high one, you dont have enough traction to support the high one.
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Old 10-24-2007, 05:10 PM   #8
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If your car is generating more corner speed with a low roll center than a high one, you dont have enough traction to support the high one.
HI

Can you explain this more Precisely?

Very Interesting ^^

Greetz
iZzy
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Old 10-26-2007, 07:35 AM   #9
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Please?
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Old 10-26-2007, 01:29 PM   #10
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Izzy!

If you read it through again, you will get a clear picture. When the traction is low the lower rollcenter will help to generate more traction, so you will have more cornerspeed / faster laptimes in the end. This is the situation in your case.

On the other hand, when the grip is high, you can make you car faster with a higher roll center setting because the car will roll less and loose less speed in the corners (= less scrub).

So if you think it over, in a the perfect situation the car will roll only as much as needed for having the sufficient traction, because if it rolls less your car will slide if it rolls more the car will slow down too much in the corners.

Hope this helps ;-)
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