I'm considering installing wilwood Residual Pressure Valves (2psi). Will this amount of "preloaded" pressure affect the ABS system?

I'm getting some knockback when diving into turns. My front end is as tight as a drum, so keeping some positive pressure on the brake pistons seems to be the next best move. I'm concerned that the 2psi created by these valves might mess with ABS. Anti-knocback springs would seem to offer a solution to that concern (as they'd apply pressure to the pistons without affecting system pressure), but wilwood anti-knocback springs seem to be as rare as hen's teeth. Hoping someone can tell me these valves don't/won't affect our ABS.

 

After road racing the Z33 in SCCA for many years, I'd be very skeptical on adding anything to the braking system that might affect ABS operation. Even if it doesn't directly affect braking, any change in line pressure will likely be determined to be a fault in the ABS operation and could shut down the system. Are you using Brembos on your Z?

 

I have wilwoods, front and rear.

 

Cant comment on the valves interfering with ABS, but there are universal anti knockback springs available at Hoerr Racing and other places which should work fine.

 

Thanks for the tip, I'll check them out. I thought I did a decent Google seArch for them, and all I found was springs that were too big for my wilwood pistons (even the sets labeled "small bore" were too large for the smaller of the two piston sizes that are in my caliper). Guess I'm not as skilled a searcher as I thought- I apologize. But then again I suppose the concern specifically about residual pressure and ABS is still of relevance

 

Also check other manufacturers, like AP Racing:
http://www.apracing.com/Info.aspx?In...10&ProductID=7

Here are my thoughts on the check valves...from what I can tell ABS/EBD work using the signals from the wheel speed sensors on each axle. I cannot find any pressure based sensors in the diagrams for the ABS Actuator and control unit. Since the system is designed to be used irrespective of pedal pressure (ie. you can be hammering on the pedal and the abs and EBD will do their bidding), I dont think 2lbs of residual pressure should affect the system if you plumb them in between the master primary and secondary lines.

Still, I tend to agree with dkmura on this one, if you can avoid plumbing into the system especially in such a critical area, that is probably a good thing. That is why I would lean to the anti knockback springs.

On a related note, floating rotors may help.