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Rear Suspension Rocker Bar

Old 01-07-2018, 09:59 PM
  #16  
Bigfoot928
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Originally Posted by dr bob
SG: Don't know why this casual thought popped into my head -- There's no torque-steer with stock the Weissach setup until the tires stop spinning. I'm not sure I've seen your car under that condition except while it was parked. I have a limited exposure period. Seemed more like you were throttle-steering...

it does have plenty of torque steer. Uturns are easy peasy....
Old 01-07-2018, 10:43 PM
  #17  
SwayBar
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Originally Posted by 928sg
in this case it means drilling a hole though the pin so that there are 2 bolts going through the "pin" and it can't move. This will disable the Weissach rear steering. With really wide 335's on the back I have thought about it more than once.
I've got 335's on the back of the racecar.
Old 01-09-2018, 10:21 AM
  #18  
Chris Lockhart
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Originally Posted by 928sg
in this case it means drilling a hole though the pin so that there are 2 bolts going through the "pin" and it can't move. This will disable the Weissach rear steering. With really wide 335's on the back I have thought about it more than once.
Sterling, what offset do you run with 335's? How much extra width is required on the fenders to fit them?

DeWolf, that's some good info. Thanks for posting that.
Old 01-09-2018, 03:16 PM
  #19  
dr bob
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For those playing along at home -- A lot of the easy to drive and invisible error-forgiveness in the 928 depends on maintaining the functionality of this bushing as a critical part of the Weissach passive steering strategy. For anything but a dedicated race car, pinning the bushing is not a good idea. My statements in post 11 above are to suggest that care is needed in selecting the correct correct bushing material, and that a firmer bushing there may not be a good idea. The factory didn't see a need to change the bushing material through the various wheel-tire-power iterations, and there is very likely a good reason for that. Remember too that this joint and bushing work in conjunction with the inner swing arm bushing to control the passive steering effect we enjoy; changing one but not the other may not always give you the result you expect. Bottom line: use caution as you modify this stuff. Racers pin the front joint to introduce some oversteer into cars that need the larger stickier rubber for traction. We don't drive race tires on the street, plus the varying surfaces of public streets, including rain, make oversteer less than desirable on trailing throttle. (ref: early 911 cars...)
Old 01-09-2018, 06:22 PM
  #20  
Carl Fausett
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I'm really glad you posted this ^

Not all things "racecar" should be assumed to be good in a street driven application, no more than all things on a street car (even a sports car) are ideally suited for racing.

I gave a lecture at the Chicago S.A.E. a few years back on just that topic. The hand-out is downloadable here if you are interested:


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