I replaced ALL drum brake components on my '64 Chevelle, added a '67 dual master cylinder to a new '64 brake booster. Now I have less braking than I did with the old setup using a single master. Now I don't know if the mc/booster is matched right.
What should I see for vacuum for this setup. The engine is modifed street using a 3/4 Crane race cam.
I can let the car idle in park for 10-15 minutes & have a ton of braking for a couple of stops. Then a lot of it goes away and levels out at low braking pressure as I drive. :confused: graemlins/angry.gif :confused:

Didn't the booster design change in 67 as well?

Maybe the booster changed. I thought it had not but could be wrong. Does anyone know for sure?