Weird Brake problem

[dodj]

 
Come on Alan, the suspense is killing everybody...
 

Good popcorn though....

[anlauto]

Still not fixed. I had a chance to drive the car Friday and it's not that bad under normal driving...it's a hard stop that you notice it pulls hard.

All the suggestions made here are great ones and pretty much all have been checked and ruled out. Only thing left is to swap out the passenger side brake line and or the portioning valve altogether, which really doesn't make sense.

[spamtank]

Still not fixed. I had a chance to drive the car Friday and it's not that bad under normal driving...it's a hard stop that you notice it pulls hard.

All the suggestions made here are great ones and pretty much all have been checked and ruled out. Only thing left is to swap out the passenger side brake line and or the portioning valve altogether, which really doesn't make sense.

I struggled with my brakes for 3 months.

Turned out to be the proportioning valve for me in the end.  Good luck.  I know the frustration. 

[Topcat]

Still not fixed. I had a chance to drive the car Friday and it's not that bad under normal driving...it's a hard stop that you notice it pulls hard.

All the suggestions made here are great ones and pretty much all have been checked and ruled out. Only thing left is to swap out the passenger side brake line and or the portioning valve altogether, which really doesn't make sense.

Is the proportioning valve an original or aftermarket?

I had Ramman re build mine as I heard the repro's had issues.

[anlauto]

It's a reproduction...

[HP_Cuda]

Replace the prop valve with a known good one and test drive.

 

[roadman5312]

  Since its only under hard braking I lean toward a suspension issue. Like movement of an upper control arm (bushing), strut rod bushing, etc.   

[anlauto]

  Since its only under hard braking I lean toward a suspension issue. Like movement of an upper control arm (bushing), strut rod bushing, etc.   

All that is 100% new and double checked....

If you drive slow on gravel and apply the brakes slowly, the one wheel starts to slid on the gravel...

[roadman5312]

All that is 100% new and double checked....

If you drive slow on gravel and apply the brakes slowly, the one wheel starts to slid on the gravel...

                         Well that blows my theory   

[dodj]

Seeing as you said the calipers were changed for different ones, the prop v and line is all you have left. Are there two outlets on the prop v for the front brakes or one? If it is one, change the line. 

[734406pk]

Its a process of elimination. Change the PV or LF brake line, whichever is easier first. BTW how are the rear brakes working? Do they contribute to stopping the car? Just want to make sure that the front brakes are doing all the work alone.

[Cudakiller70]

Check brake hoses for bulging

[734406pk]

Check brake hoses for bulging

I'm pretty sure they were replaced earlier w/ same issue. There is not much else left to change.

[dodj]

To really think outside the box, are the front tires the same?

[blown motor]

If we're thinking outside the box what about wheel bearings. A bad bearing could cause the wheel to turn hard requiring less braking to lock it up.