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Antidive/Antisquat: how much do I want?


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I did not say ALL hopping is caused by flex..... My point is that you need to look at more than one thing. The acceleration forces in a dragster are a completely different world than our application.

In our application, the unloading or loading of the suspension from the continuous forces during a climb are more a the concern with AS/AD. This moves the center of gravity around and causes unneeded suspension movement. With AS/AD over 100%, the suspension extends, raising the CG. When climbing, this moves more weight to the rear. I'm guessing people are finding better climbing with the CG as low as possible so that there is as much weight on the front as possible. More even weight distribution should result in better total traction. Also having the suspension move from link force everytime the power changes will cause a lot of fluctuation in traction and make it easier for a short term spin. Any little spin in a climb that is near the limit kill momentum and the climb.

Any of the possible advantages to AS over 100% due to the extra force as the suspension extends would not be seen in our application as we are more or less in a constant force. That extra force is only happening for a few tens of a second at most.

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Yep Drags is a very different sport and grip environment, I would just like to know as all the books I have refer to it but none explain it

....With AS/AD over 100%, the suspension extends, raising the CG. When climbing, this moves more weight to the rear. I'm guessing people are finding better climbing with the CG as low as possible so that there is as much weight on the front as possible. More even weight distribution should result in better total traction. Also having the suspension move from link force everytime the power changes will cause a lot of fluctuation in traction and make it easier for a short term spin. Any little spin in a climb that is near the limit kill momentum and the climb.

The weight distribution is important... I think more than AS%

The CoG and movement due to angle when climbing is an interesting one, there is a local 4wd engineer who works on the AS100% theory.... you have no squat there for the rear is as stable as it can be... yes, but you watch his trucks at the trials on long sustained climbs they don't do as well as lower AS% trucks and on shelves or nasty short steep climbs they have a tendency to rear up (as was pionted out above this is due to jacking on the links a side effect of the angle his links are on to get the 100%) and the trucks with lower AS% might not reach the same point but are in more control, this control allows them the ability to pick a line instead of rush

Right a truck on a slope your front end unloads lets say simple terms 45degree slope, now half the weight is now being transfered to the back axle, weight is gravity... gravity is straight down so half the weight on the spring it will push the front up

The back is an interesting one depending on the angle of the links (or leaf spring) a portion of the rear weight will be taken by the link.... the more vertical the link is the more weight it will push into the axle the greater the mass at the axle the more it locks out suspension, and the worse your axle tracks to the contour better the chance of it loosing grip and spinning, and your Cog got higher

Try the opposite flat links that don't take on much weight, the weight is transfered to the rear spring all the extra weight from the front end causes the rear springs to compress more.... with the nose climbing and the rear dropping you feel like your driving up a cliff face but back wheels can track better Now odd thing CoG dosen't move as much yet which feels worse lol

The more I think about it the more I see it is a balancing act on the link length and angle with AS% below 100%

Now John is going to come along and tell me I'm wrong..... again lol

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