15/16” pistons?

[Svtfreak]

Will a wilwood 260-14242 master cylinder (15/16” piston, 1.120” travel) be a food one to stop the 33? End brake system will be big 6 piston up front and 4 in back. What your guys opinions?

[FF33rod]

QUestion: 15/16" on each of the front and the back (2 masters)? or are you suggesting a single master?

Steve

[Kamp]

I have been following your struggles with not being able to stop your 33 and from your last couple of posts believe that you have eliminated a converter lock up issue and now believe it is a brake system problem?

In any event I am running a 490 cu engine (with a Magnuson) 3200 stall converter, 900 RPM idle and the "FFR" suppled base brake system and have no issues getting the rod stopped. One thing I had to do was invest in a small hand pumped pressure bleeder to get the air out. No amount of pumping etc. would get the system bled, the pressure bleeder took about 5 minuets! With the investment you will have in your brakes the expense of the pressure bleeder will be small.

I think there is a tendency to believe a bigger master cylinder piston will give more brake effort but its really all about hydraulic pressure. The larger MS piston will require more pedal effort (assuming no power assist) to achieve the same pressure as a smaller piston. My guess is the mfg of your brake set up should be able to give you a good recommendation on MS piston size, they know the caliper fluid capacity, take up flow amount etc, better than we do.

[Gordon Levy]

use 3/4" front and rear

[Svtfreak]

use 3/4" front and rear

Mr Gordon, assuming going with big ole brakes, that size will be sufficient to move the needed volume of fluid?

Kamp, yessir, I’ve eliminated converter. I’ve learned more about the brake system i have. The rear circuit works nothing like normal. My pump (second one) has wiped out and sucking air (no apparent leaks) which is getting sent right to the rear brakes. The pedal feels like a sponge and no amount of bleeding fixes it. Even emptying and staring over. The way it bleeds it sends air filled fluid right back to them. So, while I’m still not convinced it’s just the brakes, I’m going to fix the known problem and see if it gets me back to working good like it once did. I’ll never trust this system, as cool as it is. So, I’m going manual. And with the big brakes and right bore, it should be still quite easy to drag it down.

[Gordon Levy]

Use 3/4" master with the big brakes like mine

[Svtfreak]

Thank you sir.