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Re: brake proportioning

I know wabbits and 4k front drivers do have the rear axle activated
proportioning valves. If the rear lifts up, the pressure is reduced to
try to limit lockup. I thought quattros had fixed proportioning valves? 

Phil and Judy Rose wrote:
> OK, easy enough to test with some hard non-ABS stops. I will do and report.
> Anyway, I think my surprise at rear brake "warmth" was based on a
> misconception--namely that the steep downhill would tend to offset the
> extra weight over the rear wheels (and hence make the prop. valve ease up
> in the rear). Actually I'm now thinking it would take a *much* larger
> average gradiant than on Mt. Washington to unload the rear wheels so much.
> And as Chris Miller pointed out, the braking was only moderate, so the car
> didn't do much nose-diving to relieve the pressure to the rear brakes. So
> the prop. valve bias was probably just doin' its normal thang.
> Phil