|The MGA With An Attitude
POWER BOOSTER For MGA Brakes, #8 - BT-201H
This article courtesy of David Adams in the UK.
This is not an essential item but an interesting winter project.
There are various options for location for a servo, inside the front wing behind the splash plate, on the spare battery tray, on the heater shelf between the master cylinder and the closing panel - if you can find a servo small enough to go in, or behind the dash.
Frenos Iruna of Spain produce a 5-1/2” OD servo that will fit on the heater shelf, their model A1, but this is currently (Dec 2016) out of stock in UK and France and the manufacturer does not answer emails. I got hold of an old Type 6 Lockheed servo but the air piston was seized and the slave cylinder corroded so I opted for a Lockheed look-alike from Powertune, made in Taiwan, and decided to mount it behind the dash in the radio space.
This bracket clips to the channel reinforcement under the scuttle and is held tight by the steel strip. Neoprene sheet is stuck to the channel contact areas. The two parts of the bracket were fixed together with a self tapping screw through the hole in the first and third pictures, offered up and the parts rotated until the servo fitted and had clearance, then the overlap was marked. The bracket was removed and welded and in further trial fits the sheet adjacent to the clamp was bent downwards to raise the nose of the slave cylinder to get the 25 degree minimum upward slope required.
The nose of the slave cylinder is fixed by a bracket to the screw of the transverse scuttle support that is behind the wiper wheel box. For bleeding, I removed the two nuts at the diaphragm end of the servo so that end would fall to increase the slope of the servo for a better bleed.
The dash stay interferes with the servo air pipe so I made an alternative out of 6mm rod