brakes

I have a corvette master cylinder and servo on my 51 chevy 3100 pick up i dont know if it's the right one I have disc front and drum back and a poportional vavle for the back the more I open the propotional vavle the harder the pedal gets and the brakes don't feel as good as they should do you think i'ts the wrong setup and do I need the propotional brass block on the front of the master cylinder?

 

Are you twisting the proportional valve in (ccw)? In for more pressure to the back, out for less.
May sound "cave man", but I ballpark my brake balance on wet grass. Easy to lock em' up and not hard on the tires.
All four should lock up at the same time.
If you can't get the rears to lock, you may need larger rear wheel cylinders.

 

the more I open the balance valve ccw (more fluid to the rear) the harder the pedal gets

 

My thinking is you have a disc/disc master cylinder. These units do not have a pressure valve (which disc/drum MC's have) that prevents the drum brake springs from pushing the fluid back to the MC. This would explain the fact that the brakes don't seem to work as they should.

I say to make sure you have the right MC first, then look elsewhere. One other thought is the master cylinder is lower than the wheel cylinders and/or calipers and the fluid is flowing back due to gravity. There are valves for this also.

 

master cylinder is on the bulkhead if I turn proportioal vavle acw less to rear brakes the pedal get softer and seems to get more braking to the discs

 

Yep. With all four working in unison, get used to the pedal feel, whatever it is............

 

The adjustable proportioning valves I've used, just the opposite.
The more it's screwed in, the more pressure to the rears.
http://www.tiltonracing.com/content.php?page=list2&id=38&m=b

 

Actually you should have the front lock up an instant before the rear. the best way to check this is to have and observer watch when you lock them up. I find an empty parking lot to do it and get up to about 30 miles per hour and lock 'em up. a couple of passes and your observer will be able to determine which end locks first and then you start adjusting.

Frank

 

Try this:

http://www.mpbrakes.com/technical-support/reference-master-cylinders.cfm

 

Did you reverse the lines? Corvette master cylinders are plumbed differently. Ask me how I know.

 

so the front discs connect to the pot nearest the bulkhead a the rear to the front of the master cylinder is this right ? or will this make any difference on disc disc master cylinder ?