Pre loading on launch

Old 08-05-2009, 08:14 PM
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shortysracing
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Default Pre loading on launch

Drive a 79 camaro. Would it be a good idea to preload the rear of the car?
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Old 08-06-2009, 02:35 AM
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TS1955
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If it launches straight, NO!

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Old 08-07-2009, 04:52 AM
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BillyShope
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Unfortunately (or, perhaps, fortunately), a car can launch straight and still be losing performance because the rear tires are not equally loaded. A Camaro with stock suspension will unload the right rear due to driveshaft torque. As any roundy-round racer would agree, maximum performance from a tire pair is achieved when they're equally loaded.

Having said all that, I, too, would say NO to static preloading. The problem with static preloading is that the necessary amount is so large that you end up affecting handling on the street. You might consider some of the other techniques at my site and save preloading for fine tuning.
http://www.racetec.cc/shope
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Old 08-07-2009, 06:16 AM
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TheRabbit
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There's a lot more to it than just going straight. Eventhough they launch straight I've seen many cars and trucks pick the the left front tire 3 feet in the air and the right tire is still on the ground. In other words the chassis is so twisted the weight is not on both rear tires equally. An anti- roll bar or pre-load bar will take a ton of that twisting out and get your 60' times down a good bit. I agree, do not use a pre load bar to correct a bigger problem.
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Old 08-07-2009, 08:57 AM
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TheYellaBrick
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Any sort of motion other than forward is time being added to your E.T..
Chassis(suspension) flex and wheels up action is one way to 'soften' the launch and ease shock on the drivetrain components including the rear tires(traction).
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Old 08-07-2009, 11:39 AM
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FullTimeRacing
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What do you guys mean buy preloading?

stalling it up ?

or jacking one side up higher,like the right rear?

just want to be clear.
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Old 08-07-2009, 01:34 PM
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I think he was asking about an Anti Roll bar (or pre load as some people call it) to control side-to-side body roll during hard
launching.
http://www.competitionengineering.co...?CatCode=13048
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Old 08-07-2009, 02:01 PM
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There is a lot of good info. here. BUT, ( and I'm not a chassis guy and trying to learn) I thought an anti-roll bar was just that. A torsional bar to prevent chassis roll and pre-load was done by rotating, usually the upper right, 4-link bar to change the amount of weight on the corner of the car?

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