Yeah, read it too fast. I even double checked which direction was reduce and still typed it wrong.
Brakes Brakes Don't Feel Right After Sn95 Swap
- Thread starter Grn92LX
- Start date
Yeah, read it too fast. I even double checked which direction was reduce and still typed it wrong.
-
Sponsors (?)
squeak93
15 Year Member
So are the Wilwood and FRPP valve one in the same? @Mustang5L5 if you go back to our PM conversation I am having issues with my rear brakes not acting like they are working very well. I have my valve unscrewed (frpp valve) all the way out and have not noticed them locking up before the fronts.
Yes. Ford Racing just used Wilwood as a contractor to build their knob, but with the Ford logo on it.
Do you have the instructions for that valve? They should be the same for the wildwood valve in which case unscrewing it all the way out is full reduction to 57% pressure.
If that's the case, try going full in and carefully test to see if the rears lock up more easily now.
squeak93
15 Year Member
I did NOT get any instructions. Can't seem to find any "FRPP" ones online anywhere either. This would very much explain my lack of rear brakes and also why the car won't hold them still while in D on jackstands. I never thought to turn the knob in all the way. I just assumed it worked like a normal knob (righty tighty, lefty lucy lol). I imagine our rear brake bleeding was inefficient as well as we didn't have enough pressure going back there. I'll try this once I get the car back and report back in this thread to help with the continuity of the problems. (I won't have my car back till next mon/tues).
Screw the valve all the way in to bleed the brakes. When you are finished and have consistently hard pedal, screw the valve out all the way and then screw it back in 3 turns.
Next comes the fun part. With about a 1/2 tank of gas & whatever "stuff" (tools, jack, trouble lights, etc.) you would normally carry. Prepare to do some brake testing. Find a place that you can get up to 30 MPH and do some repeated panic stops without attracting too much attention. Make sure that there isn't anything you can collide with if the stops get too much out of control.
Do a series of 30 MPH panic stops, and note when the back wheels lock up. The tire marks on the pavement are a good indication of braking action; all 4 wheels should lock at the same time. If the rear feels like it wants to swing around, turn the valve out 1/2 turn and try again. You will get to spend some time and effort trying one setting and then another.
Next comes the fun part. With about a 1/2 tank of gas & whatever "stuff" (tools, jack, trouble lights, etc.) you would normally carry. Prepare to do some brake testing. Find a place that you can get up to 30 MPH and do some repeated panic stops without attracting too much attention. Make sure that there isn't anything you can collide with if the stops get too much out of control.
Do a series of 30 MPH panic stops, and note when the back wheels lock up. The tire marks on the pavement are a good indication of braking action; all 4 wheels should lock at the same time. If the rear feels like it wants to swing around, turn the valve out 1/2 turn and try again. You will get to spend some time and effort trying one setting and then another.
Last edited:
squeak93
15 Year Member
Thank you @jrichker and @Mustang5L5. We were going nuts trying to figure out why A: We couldn't seem to get a firm pedal no matter how many times we bleed the brakes (put 4 qts+ of new fluid through the system) and B : had no rear brake clamping force.
If I ever get the car back from the painter again(see my build thread) I'll get this accomplished as well as the new C springs installed so the front doesn't rub when it dips down during hard braking.
If I ever get the car back from the painter again(see my build thread) I'll get this accomplished as well as the new C springs installed so the front doesn't rub when it dips down during hard braking.
squeak93
15 Year Member
The car is still at paint. I am going to attempt to screw the prop valve all the way IN and see if we can't get the brakes to bleed properly and hold the wheels still while on jackstands in D.
At this point nothing has fixed it to my satisfaction but at least I have something else to try other than throw new parts at it (some more).
Put the prop valve in, screw it full in, and bleed.
If you don't get a rock hard pedal with motor off, you still have air in the lines, or a sticking caliper.
After you get pedal hard, evaluate your braking ability. The booster swap will really give you some woah factor but only if you get the system air free. Having some sponginess with engine off isn't correct.
Sent from my big ass iPhone 6 using Tapatalk
Got the proportioning valve in, very easy. I was expecting fluid to pour out when removing the fitting to install the PV but nothing. Air maybe? Got the 93 Cobra booster in, not easy 
Ended up having to knock it in with a hammer and a block of wood. Gonna tighten up the booster tomorrow and bleed the brakes. I'll report back when i'm done. Hopefully good to go.
If I feel the speed bleeders aren't bleeding all the air out i'll order up a motive power bleeder.
Ended up having to knock it in with a hammer and a block of wood. Gonna tighten up the booster tomorrow and bleed the brakes. I'll report back when i'm done. Hopefully good to go. If I feel the speed bleeders aren't bleeding all the air out i'll order up a motive power bleeder.
No fluid should pour out when you unscrew the union. It's At the highest point of the system, so if anything fluid should drain away.
Chuck the speed bleeders. They sometimes add air. I always bleed my brakes solo with standard bleeders as if they were speed bleeders. Crack line open, pump pedal 3-4 times, then go back and tighten the bleeder. Has worked well on the 4-5 cars I maintain and bleed fluid on.
Sent from my big ass iPhone 6 using Tapatalk
Chuck the speed bleeders. They sometimes add air. I always bleed my brakes solo with standard bleeders as if they were speed bleeders. Crack line open, pump pedal 3-4 times, then go back and tighten the bleeder. Has worked well on the 4-5 cars I maintain and bleed fluid on.
Sent from my big ass iPhone 6 using Tapatalk
Alright got everything done. Booster is in, PV is in and brakes are bled best I could do. Went through 2 big bottles of fluid. Some of the fluid that came out was dirty greenish looking which is odd since theres maybe 3 miles on the whole set up.
The pedal sinks right down easier now with the 93 cobra booster. I've only done around town driving so it's tough to say how much better it stops. I gotta take a ride down the parkway by the beach and do some real testing hopefully this week.
With the car off, the pedal firms up a lot better now than it did. We did get a lot of air out. Crazy how there was so much air, I must have flushed 4 or 5 big bottles total filling and bleeding the system. Seems much better now, I think I just need to bed the pads in good. Around town driving isn't cutting it.
The pedal sinks right down easier now with the 93 cobra booster. I've only done around town driving so it's tough to say how much better it stops. I gotta take a ride down the parkway by the beach and do some real testing hopefully this week.
With the car off, the pedal firms up a lot better now than it did. We did get a lot of air out. Crazy how there was so much air, I must have flushed 4 or 5 big bottles total filling and bleeding the system. Seems much better now, I think I just need to bed the pads in good. Around town driving isn't cutting it.
Last edited:
Similar threads
