Hello all, my first post..... I'm working on my '53 Ford F100, it has an aftermarket brake booster/cylinder kit on it, you know how that goes.... who knows what it's originally off of! I had the booster rebuilt a few years back and they told me that they think that the booster was originally on a Ford Granada. Well now the master cylinder seal is leaking down the front of the booster and I need to repair/replace it. It has numbers on it 348/2 and 28933 in the casting. It is a shallow piston 1" diameter dual master cylinder. I have a friend who wants to give me a brand new chrome dual 1 1/8 master cylinder. What operational difference will I see by going up a piston size? I currently have GM Monte Carlo calipers on the truck and drums on the back. My current cylinder has a restricter on the outlet of the rear line. Your input will be greatly appreciated!! Thanks, HotRod53
Going up to a 1-1/8 cylinder will lower the line pressure 27% for the same pedal force, and it will reduce the pedal travel the same amount.
UPDATE: I took a poke at ordering the master, I looked up a picture of the Granada master and it looks identical. Noone had one in stock so I ordered one for tomorrow. My buddy called me again and he wants me to try the chorme 1 1/8 master and chrome booster that he has, I'm going to pick it up tonight and eyeball it to see if it will mount to to the firewall. My Ford booster has 4 studs sticking out, the GM style bolts thru instead. The booster may be a dual diaphram and it's one of those smaller diameter but a lot deeper designs. He claims that using the combination of the two is more like the original GM design. I just don't want to end up having to stand on the pedal to stop.
After further investigation, my buddies booster and master won't fit. I picked up the one that I ordered today and I'm 99% sure that it's right. I repainted my booster since the leaky fluid destroyed the paint, We etched the new master and painted the outside with silver POR 15, it looks like it's powder coated! I'll let everything sit for a day or so to cure before re***embly, I already put the rest of the system together. I'm going to have to flush my system out, the old fluid looks like mud!
Let me get this right....................you took all the time to prep AND paint an MC that you dont even know will work on your truck? Thats like surgery before an X ray.
Yeh, it sounds strange but it looks like it's correct. I figure as soon as I put fluid in it I own it anyway whether it works or not, so why waste the time and fluid to install it and bleed it and then have to remove it all again to paint it. I didn't want to chance using that etching primer and POR 15 over a finished vehicle. I'm 99% sure it is right and if the piston is the right diameter and the lines match up, what more is there to it? I have changed many master cylinders over the years and never dove into the details of how they are sized ect, now that I see that it's really just piston size and the input piece being deep or shallow, there isn't much else to it.
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