I am in the process of finishing my restoration on my AH 3000 S/B Chevy. I have never liked the brakes. I have switched to a 11" front discs and rear drums. There is really no room to install a conventional master cylinder with a power vacuum unit. I have been looking at the remote vacuum servo units like the Sunbeam tiger comes with from the factory. MP Brakes has a similar set up. Does anyone have any experience with the remote units ?
I know very little about them, but the Hydrovac system was used on gasoline powered trucks and I believe, some cars. You might investigate that.
-Dennis
I had a Volvo Amazon from 123 GT build in1966 and that car had a remote vacuum assisted unit also. I think it was from Girling . Wished I still had the car.
Worked great.
Werner
There are several aftermarket companies that make remote brake servos (AKA "Remote Brake Booster").
The last one I bought was from Welsh Jaguar and worked excellent in the Anglia we had it in (replaced the one that was leaking internally).
Only down side I see is they only seem to come as a single circuit boost (usually the front on a dual circuit system); meaning you would need two if you wanted to boost both brake circuits on a dual circuit system.
When I bought mine it was over $400, they came down, A BUNCH!! http://www.welshent.com/product_info.php?sku=LR18230
You could use a hydraulic brake booster like ECI makes. http://www.ecihotrodbrakes.com/universal_brake_assist.html
I haven't tried them, but they seem like they would work nice, If you have the length available.
They also make a whatsit they call a "Brake Pressure Multiplier" http://www.ecihotrodbrakes.com/brake_pressure_multiplier.html If you don't have length available.
FWIW I work for neither entity I mentioned.
I would still be running the servo, but removed it when I replaced the entire Disc / Drum system it came to us with a 4 wheel disc, dual circuit system. ;)
I donated it to a friend with a '67 Volvo Amazon Wagon, to replace his, as it was leaking internally, works great there too. :D
At the risk of exposing my ignorance, I'm wondering why a conventional system could not be employed as a remote unit. The stock, single piston master cylinder would operate a slave cylinder attached to the remote booster. Most any type of master cylinder could then be used on the booster. It would require two separate hydraulic systems. At least in my simplistic mind.
Bill
It could be done, and I have seen that proposed on many forums, however it adds that many opportunities for complete failure of the brake system as any malfunction of the "primary" master, its' slave, the line between them, or any of the connections will leave you depending on your emergency brake to stop.
I looked at an MGC at an auction recently, and noticed that it had two remote brake boosters, one for the front, and one for the rear. So, it isn't as if a remote booster hasn't been done, it just isn't that common. The comments about increased complexity are valid too, although look at the complexity of the modern system. Of course they are vastly more developed.
Dennis
What about a hydro boost system (I think that's what Dennis was referring to).
They are small and powerful. Pressure is supplied by your power steering pump.
I've used the ones from a Chevy astro van in the past. And they work very well.
I hear that they came in newer Mustangs as well as larger gm trucks.
If you don't have a power steering pump, Cadillac had an electric version for a few years.
Cheers
Fred
Fred, I forgot about the hydro boost, we had one on a firetruck that had a gasoline engine rather than diesel. The unit had an electric motor
that would provide hydraulic pressure in the event of engine failure, so could be a better idea than just a vacuum booster. I looked again for hydrovac, and I needed to add "brake booster" to the term, but found examples. Anyway, off the the shop!
-Dennis
I purchased a Welsh unit 3 days ago and installed it today. It fit nicely on the RH fender well (2- 5/16" holes) and I can still change the spark plugs too. Now I have to figure out how make it more progressive in activation. It really did lighten up the pedal pressure and it will probably only be a matter of getting used to the brakes again. I'll take some photos when I figure out where I left my camera. Only two complaints. The unit came with a angle bracket and the holes that were drilled in didn't fit the unit at all. It also came with brake line and it had to be the hardest brake line I've ever worked with. I didn't need the bracket but did buy brake line extra. I also found it odd that there wasn't any instructions included although 1 vacuum connection and 2 hydraulic connections weren't too hard to figure out and also where it went in the system.
Greg
Found my camera right where I left it. Unit looks much like what Moss sells also.
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