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TheJet-09
03-02-2023, 07:30 PM
If anti-dive/pro-drive only comes into play during braking, is it fair to say that while on 3-wheel brakes there is no such thing on the RF? I can't think of how to better phrase it, but my real question then is how, or does, upper and lower control arm angle affect handling on the RF?

I remember once reading that you don't want the spindle to come "back" during suspension compression (I don't recall why), but in looking at some pictures of Longhorns (ones for sale), there appears to be a lot of angle (up towards the front) on the RF upper control arm (easier to see than the lower control arm, but it might match). I'd guess in the 5-7 degree range.

And I apologize if my question is confusing, but just looking for any comments or thoughts on the matter. Thanks!

billetbirdcage
03-02-2023, 08:46 PM
If anti-dive/pro-drive only comes into play during braking, is it fair to say that while on 3-wheel brakes there is no such thing on the RF? I can't think of how to better phrase it, but my real question then is how, or does, upper and lower control arm angle affect handling on the RF?

I remember once reading that you don't want the spindle to come "back" during suspension compression (I don't recall why), but in looking at some pictures of Longhorns (ones for sale), there appears to be a lot of angle (up towards the front) on the RF upper control arm (easier to see than the lower control arm, but it might match). I'd guess in the 5-7 degree range.

And I apologize if my question is confusing, but just looking for any comments or thoughts on the matter. Thanks!

Anti-dive is also caster gain during compression, So without a influence from a brake being applied you still have caster gain happening.

Anti-dive/caster gain is also the difference in the angle of the upper vs the lower arms, so you could have both control arms at say 10 degrees each and not have caster gain or anti-dive. However you obviously have the wheel moving forwards or backwards during travel which would be different then having both arms flat.

smartguy13
03-03-2023, 08:43 AM
Is the spindle moving back if the chassis is raked 5-7 degrees at full droop?If you set the upper control arm at the same rake angle as the lower does caster change with travel?Something to think about…Similar vein different area of the car…if you rake the motor 5-7 degrees to the left at ride height (chassis roughly level) and the chassis rakes 5-7 degrees left to right at full droop does the carb sit level or is it still sitting 5-7 degrees relative to earth? One thing to think about is how much the chassis is rolling at full droop relative to how the car sits at ride height. I think you’re spot on with anti dive assessment. If you don’t have brakes on that wheel you can’t have anti or pro dive. Anti/pro dive is a function of the difference in angle (front to back) between the lower and upper control arms and only applies when there is a torque put into the spindle. We personally run the RF lower uphill as much as possible for clearance and run out upper uphill the same angle. That way we have stable caster (thereby bump steer) on the RF. Additionally it helps keep the wheel moving more vertical (relative to the ground) than if it was level front to back at ride height.

ZERO25
03-03-2023, 11:52 AM
Anti-dive is also caster gain during compression, So without a influence from a brake being applied you still have caster gain happening.

Anti-dive/caster gain is also the difference in the angle of the upper vs the lower arms, so you could have both control arms at say 10 degrees each and not have caster gain or anti-dive. However you obviously have the wheel moving forwards or backwards during travel which would be different then having both arms flat.

Whats optimum for both?