So i Installed 2 biondo rear line lock solenoids on the rear of my daytona. Its a racecar and this is to help car hold for the burnout.

The passenger side locks the tire up but for some reason I can not get the driver side tire to lock up. When I jack the car up i cant move the tire by hand but when i set the car down, at idle the solenoid doesn't even hold the tire. Here is what I have done:

1. Bleed brakes several times
2. replaced caliper and banjo bolt
3.replaced solenoid
4. I knew the pass side was working so I disconnect it and wired this solenoid to those wire but no luck. So it isnt a wiring issue.
5. New master cylinder has been installed

The only thing I can think of is that maybe proportion valve went bad or I need to replace the hard brake line and both hydraulic hoses. But by visual inspection everything looks okay and there are no leaks and brake pedal feels rock hard.