Master Cylinder

[jjdoyle]

What master cylinder is everyone running? Does it have 5 ports? 4 ports on the left side and 1 on top?

[VMS Motorsports]

Heres the link to the ones I use (and sell)
http://www.vmsmotorsports.com/apps/webstore/products/show/1392586

[jjdoyle]

Ok yeah that is the one I have. Do you know if there is a difference in the pressure of the ports. Or in another words does it matter where you hook up each line?

[knoxracing]

The front ports are for the front brakes, the rear for the rear.

[Schmitt20]

I got a problem with my brakes. I have pressure when I'm going slow like under a caution but when were racing i can push the pedal to the floor and if i want some brake i need to bump them. I bled the brakes many times so there cant be air in the lines and also the rear brakes are adjusted correctly because I can hardly get the drums off. I had the front in the air in the pits and the pedal goes about half way down and the front wheels you cant spin at all with the brakes on. So basically my brakes quite working while racing. Could this be a master problem or what could be my problem?

[VMS Motorsports]

 
Maybe the fluid is getting hot? Check the lines to see how close they are to the engine...what are you using for fluid?

[Winterracing]

I'd check to see about the fluid, also might want to make sure there isn't any moisture in the lines, not sure if that helps but just throwing out ideas,

Dan
www.winterracing.net

[knoxracing]

1)What type of pads are you using?
2)How much free play is in the pedal, how far do you press it before you feel pressure?
3)be sure you do not have a pad that is out of place, if they are not seated in the the slots, they will not work properly.

[IraceLegends77]

I would check the pads very closely. I had this exact problem and it was the pad placement as Dennis pointed out.

Scott

[Schmitt20]

I'm using DOT 3 brake fluid, I can check the brand tonight when I get home from school. I will check toi make sure the pads are in place also. The pedal goes about half way till I get brakes but when racing no brakes unless i pump them coming into the corner. Under caution I have brakes though. I'm not sure what pads are on the car(there the same ones from when i bought the car) This is the first time I have had this problem.

[knoxracing]

The dot 3 fluid is no good, the boiling point is way to low. There is an adjustment rod connected to the brake peddle that you can extend some. It really sounds like you have a pad and fluid issue. DOT 4 racing fluid is a very good idea, do not use dot 5.  I would be interested in the brand of pads you are using. Also the rears really do not need to be adjusted to the point the drum is hard to remove. With the drum on, you can reach in the back with a brake spoon and tighten them all the way, back them off about ten cliicks or notches on each side. You really may be overheating the pads, shoes and or fluid.
Dennis Knox
Buckeye Legends

[VMS Motorsports]

I have had problems with the DOT 4 in the past, and have been using DOT 3 for the last 2 years with no issues.
Still think it could be  heat related if you have your lines bent where they're really close to the engine. Or moisture.
Maybe you lost one of the shims?

[Schmitt20]

Just checked my pads and shims and eveything looks fine. The rear brakes were not hot at all and felt cold after the heat race. This was the first year I ran DOT 3 so maybe this could be the issue?

[knoxracing]

Make sure your wheel cylinders are functioning. It really sounds like you are on all front brakes, they are overheating and fading and you have no brakes, pumping them may be due to the fact that the front fade and you are pumping the rears out to find brake.  Make sure they are adjusted properly, and change that fluid. It would not hurt to replace the pads and shoes.