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Alignment settings with or without driver weight?

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Old 08-07-2009, 05:35 PM
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Alignment settings with or without driver weight?

Is there a consensus on the best way to perform the alignment? I'm measuring a change in the front camber with an without driver weight. Initially set at target -2.5 degrees front camber with driver, without the driver, it changes to appx -2.5 to -2.6 left front, and -2.2 right front. I am trying to determine the cause of why the car seems to drift right without any hands on the wheel.

Car has been formerly aligned at the dealer, then computer realigned and corner balanced later elsewhere (with driver weight: 180 lbs. ) , and currently I'm doing by string alignment. Everything measures perfect within a fraction of a mm, front and rear toe, rear thrust angle, rear camber. On all instances I've always noticed a slight right drift.
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Old 08-07-2009, 05:50 PM
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the corner balance must be done first, with driver weight in the car...for alignment you don't need driver weight in the car...but don't change ride height once the car is corner balanced or you will change balance and alignment...if the car is aligned properly and there isn't a tire/wheel issue causing the pull then you have a potentially more serious problem

Last edited by GT3 Chuck; 08-08-2009 at 10:13 AM.
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Old 08-08-2009, 07:31 AM
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Same experience here, ride height then corner balance with driver in, then alignment w/o driver (though I've been asked at times to hold the front wheels straight).
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Old 08-08-2009, 02:10 PM
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Thanks for the replies. Any particular reason for that? It seems that after extensive searches, the majority of sites emphasize performing alignment with the driver's weight, especially with AX and track situations.

This is one quote from the Tire Rack article on alignment:
"When aligning a vehicle, it's appropriate for the vehicle to be carrying its "typical" load. This is important for drivers who continuously carry loads in their vehicles, such as sales representatives with samples or literature in the trunk. Additionally, when a vehicle is used for autocross or track events, some racers will sit in their car, or have the alignment shop "ballast" their vehicle to include the influence of the driver's weight on the suspension angles."

http://www.tirerack.com/tires/tirete...e.jsp?techid=4
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Old 08-08-2009, 03:08 PM
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while that is certainly true when corner balancing..it is not necessary for alignment
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Old 08-09-2009, 06:09 PM
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So, your saying weight doesn't affect camber or corner weight transfer? I have always set cars up with driver weight = how driven.
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Old 08-09-2009, 06:28 PM
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I have been around a lot of race cars and racing shops and none of them have used driver weight when aligning...but always when corner balancing...just my personal experience
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Old 08-10-2009, 11:39 AM
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driver's weight absolutely affects alignment. as the suspension moves the alignment changes. the suspension position (ride height) is different with the driver so ...

OP: are you sure you are test driving on flat roads? most roads have a crown, even if they appear to be flat. with such an aggressive alignment your car may be more sensitive to it than a street alignment.
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Old 08-10-2009, 10:28 PM
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Feel free to give me a ring.. Alignments and set up are what we are known for.

Happy to help and answer any questions.
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Old 08-10-2009, 10:28 PM
 
 
 
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