Axle and wheel alignment

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Loud2ns
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Re: Axle and wheel alignment

Post by Loud2ns »


I used to think that 3'' of steer in 4 ft was a good drift angle to start out with.. but like they say it's better to have enough steer to hold the car to the rail then not enough.
I would try to creep up on steer early on. That was a bad method because without a track to verify many months were lost to rail slapping runs. I now error on the side of caution with more steer.

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Loud2ns
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Re: Axle and wheel alignment

Post by Loud2ns »


I have conjectured that the optimal steering angle ought to be a function of track condition, center-of-mass (CoM) placement, and possibly track shape. This is partly out of theory, and partly because recommendations of heavier steer tends to come from upper-echelon racers who routinely operate with the most aggressive (aft) CoM location.
This has been my experience.

If unknown/rough track condition= more steer

CoM placement.
1"-¾"=less steer
¾"-under= more steer

Track shape.
Best track would be about ½" more steer than Freedom because the car may become unstable in the more aggressive transition.

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whodathunkit
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Re: Axle and wheel alignment

Post by whodathunkit »

Loud2ns wrote: Fri Feb 03, 2023 5:58 pm

This has been my experience.

If unknown/rough track condition= more steer

CoM placement.
1"-¾"=less steer
¾"-under= more steer

Track shape.
Best track would be about ½" more steer than Freedom because the car may become unstable in the more aggressive transition.

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Loud2ns.
Just trying to figure this out as the COM placement changes so does the weight on the DFW.
So more or less the weight on the DFW also plays a roll as well.. as to why more steer is needed as there is less weight on it.

( Just saying this for some weight values on the DFW to work with here.. along with COM placement changes)
Rough wood or metal track.. 19-21g or ( 0.67-0.74 oz) on the DFW.
Decent metal track.. 16-18g or (0.56-0.63oz) on the DFW.
Smooth metal track .. 13-15g (0.46-0.53oz) on the DFW.
What type of automobile can be spelled the same forwards & backwards?
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FatSebastian
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Re: Axle and wheel alignment

Post by FatSebastian »

whodathunkit wrote: Thu Feb 16, 2023 6:35 pmRough wood or metal track.. 19-21g or ( 0.67-0.74 oz) on the DFW.
Decent metal track.. 16-18g or (0.56-0.63oz) on the DFW.
Smooth metal track .. 13-15g (0.46-0.53oz) on the DFW.
Although I don't question these values, I would be interested in knowing from where they originated... probably deserving of its own, separate topic at this point...

UPDATE: Found it!
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