Need help wilwood brake pedal

[Peter Mc Mahon]

Hi guys
i have a 56 F100. The front brakes are gm metric oversized calipers ( afco 2.3/4” ) with 11” rotors. Rear is factory Ford Explorer drums. I have a older wilwood 7.5-1? Ratio pedal with twin master cylinders. My problem is my brakes barely lock up on gravel, not even close on pavement. While diagnosing I have found I only have about 3/8” of piston stroke at the master cylinders with a good amount of leg force. What could cause this? Looking for ideas to chase down and prove out. Thanks

[vette427-sbc]

what size are your masters? and how is the balance bar setup? (neutral, I assume)

[Peter Mc Mahon]

I have been chasing bad brakes for a while now, so I changed the front master to 3/4 and the rear to 7/8. Balance bar has been everywhere, max front, max rear, neutral. Brakes are not good anywhere.

[dontlifttoshift]

You have drum brakes in the rear?

Swap your master cylinders from front to rear and I bet they get better.

[Peter Mc Mahon]

Update, so I talked to Wilwood and they believed my problem was my rear circuit was engaged too early and preventing the front circuit from getting enough pressure. This turned out to be the case. The fix is crazy simple, just had to make the front master cylinder pushrod longer by unscrewing it out of the balance bar more, and make the rear master cylinder pushrod shorter by screwing it into the balance bar more. Wilwood is fairly clear on this in their instructions, but when they said greater volume circuit, I took it to mean greater volume master cylinder.... WRONG. I basically had my adjustment backwards. Ah well, live and learn

[c4racer2]

I just went thru this with a new brake setup. I needed to run as long a pushrod as possible for the rear to get the masters even at full brake force. Works well now. I have same size masters front and rear. I started with smaller rear and it was even worse - I did not have enough adjustment range in that case. Now I barely do.
My setup is temporary using factory style rear brakes with StopTech fronts. Soon will have StopTech front and rear and it should need a lot less initial skew to get even at full force. We shall see

[Peter Mc Mahon]

According to Wilwood, your aiming for “even” no skew, on the balance bar at 50% stroke. After 50% stroke when the balance bar equals out, the skew will return in the opposite direction.
Other than that , more volume of fluid being moved during braking, gets the longer pushrod.
Equal balance bar at full pedal with equal sized master cylinders would mean equal brake force front and rear ( line pressure) and I don’t think you want that?
What size pistons front and rear do you have?