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Old 05-29-2006, 09:59 PM
  #49  
BigDogRacing
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Carbon works- Ralph didn't exactly "tell" a guy that posts on here how squat works... Rocko works for Ralph at RCAmerica. Rocko doesn't post much, but his posts are always informative. Ralph almost never posts cause he's so busy but many times will ask Rocko to post information for him.

Rody- you guys are 100% screwing up racers trying to learn chassis dynamics.

The biggest misconception in squat and dive is simply this: Normally weight transfer causes the car to lean towards where the weight is being transferred because of roll moment and the CG being higher than the instant centers. However, in the case of squat, it's not about the leverage of CG over roll centers, it's about torque and the opposing forces created by rotational mass.

With a solid axle suspension (like a 1970 Chevelle for example) the pinion gear tries to climb the ring gear and effectively forces the axle to push away or separate from the chassis. That force drives the tires into the pavement and in some cases where the instant center has been modified, will actually apply more than the car's total weight to the tires momentarily.

With our independant suspension cars, that pinion/ring gear action is absorbed back into the chassis, but a Carbonworks stated, the angle of the hingepin still causes a reaction of the rotational weight (tires, wheels, axles) against the unsprung weight of the chassis.

Sometimes I have a hard time understanding new concepts such as this and find that using extreme examples help me to understand, so here's one that will help... Think of the rear hingepin being at a harsh angle like 45*. You're looking at the car from the driver's side and that angle is like this- /

-so the car might be represented like this: <O___/O (with the slash being the rear hingepin angle) It's easy to see that when the rear tire tries to roll forward, it will also try to move up as well. This takes weight away or off the rear tires even though the rear of the car will drop immediately. Hence the name prosquat.

- the direct opposite of this is true as well: <O___\O Now it should be very simple for you to see that when the rear tire tries to accelerate, it will move downward and try to push the chassis up. This applies more weight to the tire and also reduces the amount the rear chassis squats down; antisquat.

Hope my simplification helped someone. If it did, please buy an Xray...lol.
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