C4 rear Anti-squat mod: Pros and Cons?

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The Artist formerly known as Turbo84
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I'm seeing an aftermarket company selling different brackets to modify the rear anti squat, promising to improve everything (drag, autocross, and road course). I asked for technical details a while back (as I'm suspicious of anything that promises everything), but just got a lot of grief for it from other posters. So, what's the pros and cons of this modification? (I believe this part reduces the anti-squat.)

thanks
 
Who's selling it? Doug Rippie? I know they have camber strut brackets for improved roll center location.
 
Oh yeah those.lol From what I hear, the DRM brackets do help.
 
Oh yeah those.lol From what I hear, the DRM brackets do help.

I'm looking for some actual engineering reasoning to confirm that. I'm not coming up with anything other than the ass end will just squat down more under acceleration, which causes a camber change, and a net reduction of traction.
What am I missing here?
 
Never used it but as far as anti squat goes, you can only go so far with IRS because the torque reaction is not located in torque arms but in the chassis, so the effective moment is much less.

Antisquat.jpg

Do realize that altering the anti squat/pro squat characteristics may alter ride comfort. It has to do with the way the suspension moves up and either fore/aft and the amount it does so. Visualize an obstruction and the suspension for instance moving up and forward, The susp. Literally moves up and into the oncoming obstruction, making the reaction a lot more violent than if it were to move aft.
 
There si no way to change the antisquat changing the pivot points of the toe links!!!

The only way to do it is to change the pivot of the trailing links.... moving the end of the swing arm higher.

The system from DDR only can modify the bump/torque steer of the IRS.

Even the roll center cannot be changed.... if you don't move the pivot point of the strut rods.
 
No, the bracket changes the dog bones angle and orientation, it's the forward bracket that bolts to the rear tub in the C4
 
What he has are two different changes. He has a bracket that lowers the camber rod. To me it appears he lowers the camber rod inner which would reduce the cambering through the travel. Saying it creates better tire contact changing the geometry.
http://dougrippie.com/?p=1286

Then he also widens the distance between the dog bones forward from 3 15/16" to 4 15/16". Which I am guessing is the similar to your design Pierre for the C3. Not sure what angle the dog bones are at. Creating squat.
http://dougrippie.com/?p=1272

http://www.racecars360.com/Corvette_Tech/C4_Rear_Suspension_-_2_files/shapeimage_2.png
 
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Of course...... I only have seen the picture of the toe-rod..... and I was talking about this one!

If there is an other kit moving the dog bones higher in the frame, as allready mentioned, this will change the antisquat!

But must be taken in consideration the fact that a higher antisquat will increase the risk of wheel hop when braking hard!
 
Pierre, the mod removes the anti-squat not add more. Go to page 2.

"In the late eighties Doug Rippie, and a few others, discovered that what was ideal for the street wasn't necessarily the best thing for the race track. Getting the Corvette to squat during acceleration could actually be a good thing. The idea is that as you exit a corner you want more weight transfer to the rear. This gives you a little extra traction on exit. Now you can just reverse this process when you brake on corner entry. The extra transfer to the nose plants the front tires just a little bit better."

http://www.racecars360.com/Corvette_Tech/C4_Rear_Suspension_-_2.html

I'm thinking with a factory setup you are running softer springs. So the squat you get is more, this is engineered in the factory car (softer springs) for ride comfort, so the anti-squat is added. Racers tend to use higher spring rates removing much of the squat. But some squat is good.
 
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I agree!

At the track the antisquat is not really a concern, is more effective a good balance wher braking hard!
In fact you have to launch hard only one time at the beginning of the trace...... but any corner of any lap, if you can brake harder than your competitor, can be a good point where to overtake.

Like allways talking about suspensions and setup...... the balance is a compromise..... and wath is perfect for you can be the worst thing for an other driver!
 
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