Allard Disc Brake Applications
The first works produced disc brakes system was fitted to the Jaguar powered Mk2 GT chassis, Sydney’s car which had been developed from the standard Mk2 Palm Beach. The drum brakes the Mk2’s had started life with, Lockheed 12 inch diameter by 2.25 inch, were adequate however their self adjusting version had its problems. As far back as 1952 the Stirling Moss C Type had won the 12 hour Rheims race which heralded the advantage of discs over drum brakes. Their shorter breaking distances improved lap times by a large margin and if there had been an updated version of the JR for the 1954 Le Mans disc brakes would have been used. The fortunes of the Company at this time were at very low ebb, and sadly the two JR’s of 1953 were the last Allards to compete at the Le Mans. The JR chassis built in 1952 for Tommy Sopwith (the Sphinx), left the works with Lockheed drum brakes however we were required to supply drawings with the car so that Dunlop could investigate fitting both front and rear discs – whether they were ever fitted I have no knowledge.
Sydney’s GT (7102) was fitted with Girling 11.75 inch diameter front discs, however the rear drum brakes were retained. At this time front disc and rear drum brakes were the norm, possibly due to the poor performance of the disc linked hand brake. The Allard set up did not use a conventional vacuum servo but an Australian designed hydraulic ‘booster’ which provided the extra line pressure needed to get a balance between front and rear braking effort. The road test of the GT by Autocar stated that braking performance ‘proved adequate with maximum retardation of 88 per cent was above average’, it did comment that pedal pressure was heavy by present-day standards. The Chrysler GT, currently own and raced by Bob Girving had the same disc brake system, along with the last Allard produced Mk 2 Palm Beach (7107).
The Company was now deeply involved with the Shorrock supercharger installations, suspension modifications for the Ford 105E small saloon, including a disc brake conversion, which was a standard fitment on the Allardette. Over 1000 sets of this conversion were produced probably being the most successful conversion kit we produced.
Prior to the Chrysler Dragster, which at the insistence of the UK RAC, construction rules required front brakes were fitted and a modified version of the Ford conversion system was used. Sydney’s Steyr powered ‘Sports Car’ used front discs along with aluminium Girling callipers, and lastly the twin engine Steyr ‘Sprint Car’ had a single front disc which ran at crankshaft speed.
In 1957 a prototype set of discs were supplied to a customer in Peru for his J2X, (believed to be chassis number 2223) using the Mk 2 Palm Beach 11.75 inch discs and callipers, along with special wire wheel type hubs and steel calliper mounting brackets. Whether these were ever fitted remains a mystery because some months later we had a letter from the Allard’s owner’s mother to say that her son had been killed while racing his Austin Healey.
Ignoring a number of Allard specials which have been fitted with disc brakes, Jim Tiller’s J2 – ‘Old Fella’ was a project I was involved with and used a set of AP Racing 12” diameter ventilated discs and four pot callipers. The rear on this application used E Type Jaguar discs and callipers, incorporating the handbrake arrangement linked to the Allard fly off hand brake lever. Prior to fitting the AP system Jim had used a front E Type disc brake set up which was a considerable improvement over the original Allard drum brakes, however they had their limitations.
