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This is the 5th of a series of “How to” articles. FRONT END For those of you who have made a conscious decision to improve on young Stanley’s front end configuration, there are a few points to ponder. Except for early cars intended for voiturette racing in France and Italy etc, most of the serious mods to the front end occurred after Stanley had left “the Austin”to join “Wagonlites” (light rail carriages to you). Our Aussie mate, Arther Waite, instigated most, if not all, of the major changes until Murray Jamieson entered the scene. Sadly, not one book on Austin Racing has the correct sequence of changes; some publications have so many errors as to make them almost useless.. One thing does stand out;any car prepared by Arthur Waite usually finished, mostly with class wins. An outright win at Brooklands at an average speed of over 80mph was in a car Waite was supposed to have driven but he had not recovered sufficiently form a previous accident. Instead , the drive went to the Earl of March and Sammy Davis (not the song and dance man) One other source of misinformation was the good “Lord” himself who insisted that in all Publicity, Austin’s success said no more than that the winning car was a specially prepared standard model available at your local Dealer. After some success on the Continent, the need for a more stable car became obvious. The trim of the car could be altered simply by flattening of the rear springs but the front was not so simple. The need to “bow” the centre section of the front axle some 2/1/2” and reverse bend the front spring so as to lower the front of the car was only the beginning of the re-engineering. The standard radius rods now touched the chassis rail so the front of the radius rod had to be redesigned to stop this-and still maintain the castor control from the mid chassis point. The two steering arms, both Left and Right, had now to be altered, i.e set down 2’’ to match the bowed axle and stop the track rod striking the underside of the chassis. The steering arm itself had to be set down 2” to allow the drag link to operate in the horizontal plane. All this is known as “Ulsterizing” the front end. It appeared on some early Supersport cars and later on Super Sports 1929 on; these cars were later called “Ulsters” because of successes at the Ulster TT.. The Factory Catalogues however refers to the blown cars as Supersports and the unblown cars as Sports. All these changes produced a car with greater cornering speed and straight line control. Looking at some cars today, a number of errors occur regularly. The first and most obvious is the front spring which still has a positive camber and a gap of about 5” between the top of the axle and the bottom of the “u” bolts . This is achieved by making the front spring negative camber when it should be 1”. From the centre of the shackle eye to the top of the spring should be about 2” plus and the correct “front spring packing piece” in place (the flat side against the chassis mount, the convex curved side to the spring) and the spring when fitted will neither gain nor lose camber and the car will effectively be lowered 2/1/2”, setting the castor and camber as normal. When setting the castor (5-7`) with a lowered chassis, the chassis must be level on level ground; you cannot set castor correctly on sloping ground nor with a chassis that is not itself level so all work on the front end needs to be completed before resetting the rear springs. To allow for 2 people, the rear of the chassis should be ½”higher than the front. All measurements for level must be taken from the bottom or underside of the chassis using either a steel rule or spirit level (why the underside of the chassis? ).This is the only continuous straight line, the top of the chassis rail continuously tapers from the rear spring mount to the nose piece. Now the steering draglink must operate in a horizontal plane or as near as can be achieved to prevent the steering box arm going “overcentre” with the resulting rise in heartbeats. When bending the steering arm down at the ball-joint end, the nut securing the steering ball will just clear the top of the front axle by about 1/10” The steering box on the Duck Racers was raised some 3” by mounting the box on the side of the crankcase to make the draglink operate in a horizontal plane. John Bowring |