Torque steer is governed by many things... two FWD cars with the same power levels can have greatly varying amounts of torque steer.

The main factors that contribute to torque steer are:

Spindle length (the horizontal distance from the wheel centerline to the kingpin axis at mid wheel height.) The SL is in effectively the moment arm that the imbalance of forces will act around. Make it low and say goodbye to torque steer (20 mm or less is low) The viggen through use of different offset wheels than the 9-3 base or SE actually has a greater spindle length than either vehicle and has more torque. bad combo...

Half shaft angles. In order to keep the component of torque acting about the left and right kingpin equal the halfshaft angle left and right should be kept equal.

Compliance of half shafts. The torsional stiffness of the halfshafts should be fairly equal to minimize transient inequalities of torque from left to right.

Compliance of suspension and chassis components. If poorly designed, the engine torque can cause steer effects on the suspension through bushing deflection.



Many people on this board do not like to call the steer induced by engine torque on the viggen torque steer but rather prefer to call it "camber steer" I do not subscribe to this terminolgy nor agree that the slight difference in camber angle from left to right wheel are first order effects on the steer induced by engine torque. I have pointed out before that the lateral force generated by camber of the wheels is slight in comparison to the above effects. (especially when you consider the _small_ differences in camber angle between left and right wheel under full load) The "camber steer" term can be used to describe the fact the vehicle tends to pull slightly to one side or another depending upon the camber of the road.

-Joe

• Viggen v. TT for Torque Steer, bob, Wed, 13 Jun 2001 16:13:03
  • Re: Viggen v. TT for Torque Steer, Increased Tire Pressure, Sat, 16 Jun 2001 18:49:19
  • Re: Viggen v. TT for Torque Steer (long), Dean, Thu, 14 Jun 2001 09:19:24
  • Re: Viggen v. TT for Torque Steer, 2Slow, Wed, 13 Jun 2001 16:55:45 <-- Viewing This Message
    • another view, Kevin K , Fri, 15 Jun 2001 10:32:45
      • Re: another view, 2Slow, Fri, 15 Jun 2001 12:49:06
        • Re: another view, Kevin K , Fri, 15 Jun 2001 15:03:41
    • Why then does the "torque steer" virtually dissappear, Talladega900, Wed, 13 Jun 2001 17:28:43
      • Re: Why then does the "torque steer" virtually dissappear, bob, Fri, 15 Jun 2001 11:41:22
      • Re: Why then does the "torque steer" virtually dissappear, 2Slow, Thu, 14 Jun 2001 08:39:43
        • Ahh. I see what you're saying. Really a matter of semantics, Talladega900, Thu, 14 Jun 2001 11:07:33
          • Perhaps this helps explain why "camber steer" is a misnomer..., 2Slow, Thu, 14 Jun 2001 12:51:54
            • I thought camber steer referred to..., LDH, Thu, 14 Jun 2001 13:17:22
              • Re: I thought camber steer referred to..., 2Slow, Thu, 14 Jun 2001 13:30:47
              • Re: I thought camber steer referred to..., 2Slow, Thu, 14 Jun 2001 13:24:50
      • Re: Why then does the "torque steer" virtually dissappear, Brad, Wed, 13 Jun 2001 19:25:01
      • It reduces compliance, Schu, Wed, 13 Jun 2001 19:15:02
    • Very good input Joe, Schu, Wed, 13 Jun 2001 17:10:52

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