rossint wrote:The Wilwood valve actually adjusts the knee point based on the pressure it sees rather than just restricts flow through the valve across the board, It is a proportioning valve.
I'm sorry but not correct. You have master cylinder pressure upstream going into the w/w valve, & the knob sets the pressure at which the downstream pressure will not rise above. In theory it doesn't have a proper knee point, just a manually adjustable, pressure setting.
When braking, the pressure downstream will be the same as upstream, up to the setting of the valve. Further heavier braking past this pressure will not increase pressure coming out of the valve to the brakes.
A proportional valve adjusts the pressure in the rear brakes according to the pressure in the m/c. The manufacturers design it to give the best f/r bias according to the cars 'setup' & general driving. The rear pressure is always increasing as the front pressure increases, just at different rates above & below the knee point.
The w/w valve is placed in the rear line, & is adjusted to give a maximum downstream pressure that the rear brakes see. The w/w is not allowed on a road registered car. Two reasons would be:
- people can back the knob off too far, maybe reducing the rear pressure too much & giving inadequate rear braking, OR
- screw the knob right in, giving the rears full m/c pressure, which could cause the rears to lock & the car to swap ends