Common MG TC Modifications and Mechanical Issues in the early Racing Era – Part 3, by Bob Watts
Part 3: Common MG TC Modifications and Mechanical Issues in the early Racing Era
It’s difficult to separate Bob’s article into distinct segments, but this one tends to focus on the major mechanical issues with which TC racers had to deal in the mid 1950s. I can recollect going along for the ride as a small boy on a few rescue missions similar to those recalled here by Bob in this article. At left is Harley’s original TC, which was rolled (by another driver borrowing the car) and significantly damaged, in the very event at which this photo was taken.
I only reached the age of being able to recall specific memories near the tail end of Dad’s active automobile racing support activities. I only vaguely remember Jaguars and Ferraris and Porsches and other exotica in our driveway, and hanging around with my Dad in the shop, listening to grown-up talk about the automobiles they were working on, and getting to take fast test rides in exotic cars with my Dad at the wheel. Only later in life did I learn to appreciate that what seemed like commonplace activity in my childhood was not common with other children of my generation. Consequently it might be easier for me to appreciate these anecdotes, having been blessed with the opportunity to witness the tail end of an era which is now gone forever. – editor.
About 1955 Bob Fergus was trading for various cars he wanted. He traded for a chain drive Frazer-Nash and felt his side of the trade was worth much more, so a 1931 “C” type MH Montlhery Midget was thrown in to make up the difference!
Efforts to improve TC performance were made by Don Marsh, who installed a Marshall blower, and by Phil Miller who got Harley Watts to install his Italmechanics blower. Ray Fisher also added a blower, and others raised the compression ratio, polished intake ports, installed larger valves, heavier valve springs, installed high compression pistons, larger SUs, changed SU jets and needles, installed a competition clutch, removed the air cleaner, installed a competition coil, changed spark plugs, reduced back pressure with a straight pipe, replaced rear wheels with 16” wire wheels, etc. Also it should be noted the much quoted 54 hp if the XPAG engine was on 72 octane gasoline, which was all that was available in England in late 1945. “High test” pump gasoline here, was 87 octane. The heavy, air scoop front fenders were sometimes replaced with shortened ’35 – ’36 Ford spare tire covers from the junk yard. These were shortened to make skinny cycle fenders. Weight reduction also included temporary removal of the windshield and bonnet side panels. These later modifications were only for more serious competition.
Phil Miller’s supercharger made a noticeable difference ion the car’s performance. I followed Phil in his TC to visit the Greiner Brothers on the east edge of Springfield the summer of 1950. Following a noisy ride in a Mercedes 540K, we headed back to Columbus on Route 40. Phil put his foot in it and I tried to keep up in my Pontiac. The speedometer hand in the Pontiac went out of sight behind a shield at an indicated 100 mph. During much of the return ride the speedometer hand was out of sight. I’m sure the speedometer was optimistic, however the TC would pull away seemingly at will. I don’t know whether stronger valve springs had been installed on the TC engine, but Phil had to be running at or near 6000 rpm much of the time. 15.64 mph per 1000 rpm at 6000 rpm is about 95 mph. The TC had to be running at or near this speed much of the 40 miles to Columbus.
TCs were driven hard and mechanical problems were accepted as normal. Harley Watts with one or two others, probably Don Marsh, Bob Fergus, and/or Chuck Dietrich, late on a Sunday afternoon, called from Wapakoneta with a broken rear axle. A spare axle, without the normally pressed on bearing carrier, was taken to him. The broken stub had been removed by removing the opposite wheel and axle and pushing it out from the opposite side, possibly with a jack handle rod. The replacement axle was installed after dark in an unlit gas station lot in a very short time. The TC was promptly driven back to Columbus. The bearing carrier was originally pressed onto the axle with some seven tons of pressure. However the constant shock of up and down shifts, hard braking, over revs when airborne over bumps, such as railroads, etc., loosened this spline connection, and it became normal to accept the bearing carrier-axle spline connection to a finger tight sliding fit. As a result, spare axles were usually were usually carried without the pressed on bearing carrier. A related problem was wet rear brakes from differential grease finding its way through the splined axle bearing carrier connection and past the grease seal onto the inside of the brake drums, and also onto the rear wheel spokes. Normal hard cornering threw the differential grease to the outside of the case with enough pressure to force it through the ineffective bronze return thrower also. With these “leaks” onto the rear brake linings, rear brakes were often almost non- existent. Frequent hard braking was known to burn the paint on the brake drums on all four wheels.
Occasional fuel pump failures caused spares to be carried. Windshields were replaced often from rock damage, frequently from driving on gravel roads, Aluminum rear plate engine supports cracked or broke from the shock of landing after aviating over a railroad crossing or other bumps as well as the general rough pavement.
At a Put-in-Bay race, a TC coming into town from the Cemetary on a rough, bumpy section of road, developed violent front axle tramp, so violent that one front tire hit and broke one cycle fender off. Tire marks on the underside of the clamshell front fenders of hard driven TCs were not uncommon from similar front axle tramp.
Bishop cam steering was often not kept full of 140 weight “grease” or temporarily filled with chassis grease, and deteriorated rapidly. Tompkins kits, when they became available, were enthusiastically adopted. Hard driving required at least weekly, if not daily attention, to all lube points.
Tire wear was rapid. Less than ten thousand miles of driving exuberantly was all it took to run Dunlops from new to bald. Pirelli tires were discovered early on. They were “stickier” and wore for many more miles. There are still TCs around being driven with 40 year old Pirellis. These tires were made in England.
Front wheel bearing replacement at frequent intervals was routine. Chuck Dietrich replaced his after every race. King pin replacement was done fairly often.
Stay tuned for the final segment – “Where are they all today?”