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Old 09-30-2011, 12:29 PM
  #36538  
SlowerOne
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Join Date: Jun 2005
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Originally Posted by InspGadgt
I may be wrong on this but...my understanding it is to get even dampening left and right. With a single damper to get the same angle on the damper on both the left and right of the pod it would have to be attached to the center of the pod but that throws the weight off on the car unless you do something like what 3Racing did on their F109 which attaches the center of the damper to the center of the pod. If you attach a damper off-set to one side so that the damper can be centered then the arc in which the pod end of the damper moves is different from left to right. Using 2 damper tubes instead takes a lot of geometry out of trying to figure out where to mount the damper.
Almost there - the reason a single damper is not preferred is that the amount of damping changes left to right. As the damper piston withdraws from the cylinder you get less damping area, and as it goes into the cylinder you get more. With two dampers you get the same damping all the time - as one piston withdraws the other enters, so the overall damping area is unchanged. The angles are no more of a worry than on the centre shock, but the area of damping is the concern. HTH

Originally Posted by AreCee
So they were using something like diff-lock then? What were the tube guys using on their tubes? 100K? How heavy were the springs they were using?

I use 20wt on most tracks and if the grip gets real high I may use 40wt but so far I have not found a track with grip that high. However, I race my AE in 17.5 open boost class so maybe a 4.5 puts higher side loads on the chassis. I don't know.
The word 'lock' is misleading. The word 'pack' is more appropriate. When the car starts to roll, thicker oils require more energy to get moving past the piston, so the car momentarily 'stops' rolling while the energy builds up to get the chassis on the move. With thinner oils, this is not a problem. I use the standard shock with 20wt and no problems. With such little movement in the shock, anything over 30wt is going to give you that problem.

Sometimes the roll rate is mistaken for the rear when it is the front that is the culprit. If you want less roll, stiffen up the side springs, not the oil. Oil and springs must be matched,otherwise the car will not snap out of turns straight, and will be lazy in chicanes.

Side dampers don't suffer from this problem, and it why they are coming back into fashion with various chassis alternatives available. However, they need more work and they are less consistent from one rebuild to the other for the average driver. HTH
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