Landracing Forum
Tech Information => Steering - Suspension - Rear End => Topic started by: Tzoom on July 05, 2008, 01:10:13 AM
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What caster and camber (king pin angle?) to you use on a straight front axle?
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Methinks it's deju vue all over again.
Those topics have been bandied about for at least the last ten days- there a huge amount of information and good opinions in the recent Land Racing archives if you take the time to search.
Good hunting!
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I did and I read anywhere from 6 degrees to 30 degrees of caster so I guess I've pretty much nailed that down but I didn't see anything about camber except for Sum's statement that he is "shooting for no camber".
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Currently building axle for new car. 13 degrees caster - 0 camber - 0 toe - 0 scrub - should go fairly straight. 13 degrees is a subjective number, whatever works, I raced a few Uyehara funny car chassis and that was Dave's choice, worked for me, f/c spec is as close to running as LSR and it still has some steerability at slow speed.
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Thanks. I was looking at photos of funny car/altered axles in a Mark Williams catalog and it looked like they had about 10 or 12 degrees of camber. Seemed like that would cause a lot of drag.
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There is no drag until you turn the steering wheel.
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Don't forget spindle kingpin inclination - kingpin is NOT 90 degrees to wheel spindle plane - usually about 8 to 10 degrees difference based on original design.
Ed
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There is another thread in this heading that addresses scrub and king pin angle. A must read if you are building an axle. Originally I looked through all the catalogs to buy a finished axle, came to the conclusion build it from scratch to meet your particular needs.
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Wow! No lack of information on that thread. I'm going to have to print it out and study it more. Thanks
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I see how 1/8" tow-in is recommended for "used parts" -- so the slop doesn't result it toe-out. I think zero is almost unobtainable and would err on the tow-in side -- just to be safe. Front Runners seem to search at high speed on salt -- our preference is for the grooved tires such as M&Hs. (Now we're arguing Ford and Chevy . . . )
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stan is right---one thing though toe is something you can check yourself --jack up the front of the car --spin the tires (front) and mark them around the outside of the tire with a ink pin as close to the center as possible --now let the car down and push it backwards 8 or 10 feet --now push it forward 8 to 10 feet (you did that because the tires try to tow out when the car moves forward) now check the tow by measureing from line to line (wheel to wheel ) in the rear as high as you can (ideal would be half way up the tire --spindle height ) now measure the front (same height ) subtract the front from the rear if you come up with 0 to 1/8 (narrower in front) inch you are good to go --if the front measurement is bigger than the rear you have toe out---not good--make your adjustments and push the car backwards again 8 to 10 feet then forward 8 to 10 feet and check your measurements if there off repeat until they are right on the money pushing the car backward then forward after each adjustment --you would be suprised how many cars ive checked fresh from the alignment shop and they were off now i always do my own then i know its done--it is important to have good parts with no play if you dont fix that first--all of the drag race cars we set at 0 toe on dirt or salt i would run 1/8 toe in --im only talking about straight axels here if you have a arms look up the specs for your car --us bike guys dont deal with such things LOL willie buchta