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racerkrp1
04-12-2011, 07:47 AM
Does anyone use a Residual Valve on the brake lines at the master cylinder on their car and do they work? Thanks

frontrunner
04-12-2011, 05:17 PM
Well I just put 2 of them on and didnt take me long 2 take them off becouse after I would hit the brakes my brakes would not release till I opened the bleeder on the calape... I thought that they would have helped sence my calapers are mounted low but they dint so took them off & works fine now... They were the 2psi

stock car driver
04-12-2011, 09:54 PM
you only need them if u have floor mount pedals so your master cyl is below the calipers

gravity works for hanging pedals

racerkrp1
04-13-2011, 06:48 AM
OK Thanks, I am just trying to figure out why I keep loosing the brake pedal and I have to pump them up. I have reverse bleed them also. All the rotors run true. Any ideas? Thanks

stock car driver
04-13-2011, 10:06 AM
do you have disc on the rear?

do you have bias so you can see if you have weak front or rear?

if rear is soft or pumps up. you probably are running thin rear rotors 1 inch or less and dont have spacers behind the pads to make the calipers work properly, calipers for front are for 1.25 thick rotor and when the piston is out too far its spongy or you have to pump the brakes.

I didnt know this until 2007 or 2008 and on dirt I would spin out like a idiot a lot.. it was my brakes being inconsistent as well as I had to pump them down the straights all the time....

I started winning races and the only change I made from also ran to winner was spacers in the rear and racing pads all around so I had good brakes.

racerkrp1
04-13-2011, 02:42 PM
Stock master cylinder, stock front rotors, 1.25 rear rotors, d-52 pads front and rear, good pedal until I race then it goes about to the floor and I have to pump them every corner. Changed master still the same.

turner
04-13-2011, 03:59 PM
Hey Jeff.How can you tell if you need spacers on your rear calipers?? My calipers are 1" thick.Is there a distance you want the piston sticking out of the caliper, or is less sticking out better? Thanks for any info.

stock car driver
04-13-2011, 05:35 PM
Turner, less better... for sure.

.81 thick rotors for sure need spacers.

I bet on the 1 inch thick ones you could use a old pads backing plate and help your pedal some.


To the floor? When you say stock master there are many different stock ones. If they pump up then the issue is just air most likely.

Do you by chance have the oem proportioning valve in the system still? If so theres a button on the end that you need to RE set in order to bleed the brakes or get them to work properly.

I like to let gravity bleed my brakes, Ill open the bleeders on the rear with the front jacked way up and let them drain to change the fluid so to speak every once in a while. I jack up the back to do the front, it does make a difference as it gives it enough pressure in the line to push up the up hill places in the line.

ace1
04-13-2011, 10:25 PM
Is your suspension in the stock locations?
We race modifieds and was having a similar problem. We would have brakes at the shop but hit the track and first turn and no brakes. I put the valves in, replaced calipers, rebuilt master cylinders, bleed them over and over, everything I could think of. After about 4 weeks of knocking the rf off the car I happen to jack the left side of the car up high and was looking things over and noticed the rr spring against the caliper which was pushing the piston in on that caliper. I had made some changes on the rear suspension and had the rr spring too close to the caliper.

stock car driver
04-14-2011, 07:24 AM
Is your suspension in the stock locations?
We race modifieds and was having a similar problem. We would have brakes at the shop but hit the track and first turn and no brakes. I put the valves in, replaced calipers, rebuilt master cylinders, bleed them over and over, everything I could think of. After about 4 weeks of knocking the rf off the car I happen to jack the left side of the car up high and was looking things over and noticed the rr spring against the caliper which was pushing the piston in on that caliper. I had made some changes on the rear suspension and had the rr spring too close to the caliper.


Good point, Ive had my rr caliper hitting the frame before and it would push in the piston and it took a few pumps to get it back out and working...

bushracing67
04-14-2011, 09:20 AM
i had a metric spindle bend at the caliper mount, it twisted the caliper a bit and it took 3-4 pumps to get brakes... chased it for a few weeks before i figured it out

racerkrp1
04-14-2011, 11:09 AM
I think I might have found the problem. I started the car and ran it in high gear and found the cheap ass Speedway Motors stamped steel hats were wobbeling. I have new aluminum hats on order will let you know if this works...

roybeckett13j
04-14-2011, 03:11 PM
If you have good brakes for a bit, then it goes away like you said...usually means you have some sort of contaminate in your brake fluid. Air/water..ect, try draining ALL fluid out, putting all new fluid, from a just opened container, into the system...then sufficiently bleeding them.

you also might have a mount flexing. These mounts I see in speedway don't EVEN look solid enough for the kind of pressure brakes see. Also could be a worn set of caliper bolts, allowing too much deflection.

stock car driver
04-14-2011, 04:18 PM
I think I might have found the problem. I started the car and ran it in high gear and found the cheap ass Speedway Motors stamped steel hats were wobbeling. I have new aluminum hats on order will let you know if this works...

A bent or warped rotor will do what your having as it pushes the piston back in then you have to pump it out etc...




Roy, you should be removing the rubber grommetts in the calipers so your calipers have a ton of slop at both locations on the bolt. I dont think you could wear a caliper bolt enough to make it any sloppier... you can move the calipers around about a half inch when you remove the bushings and have everything working right..

bushracing67
04-15-2011, 06:33 PM
for sure on the wobbling hats, that would cause exactly what you were describing, +1 on removing all the rubber o-rings on the calipers, a must do on dirt