J-Series MGs (cont’d)
I believe the fastest TT-bodied two-seater J4 performance was that of Hamilton’s car, which was second in the 1933 Ulster TT at around 73 mph and later exceeded 110 mph in that form at Brooklands. The same chassis configuration, but with a light single-seat body, lapped the Weybridge Track at over 120 mph.
I relinquished my J4 in 1938, and did not see it again until recently. I discovered it now belongs to Dr Karl Weissmann, a great MG enthusiast who has three or four of the pre-war works supercharged cars (K3 and J4) and who has rebuilt my old car to a first-class standard. Naturally I could not resist nipping over to Lubeck, near Hamburg, where he lives in a house which he has practically converted into a shrine for old racing MGs.
Though now painted red instead of the original British Racing Green, the car looked better than ever and Karl let me drive it around Lubeck. The thrill of being permitted to do this after an interval of nearly fifty years was a milestone in my life, and to see it in such excellent condition was most exciting.
I had not forgotten the car during those fifty years; indeed I had made strong efforts to re-trace it in 1949 when I was stationed in Hanover. There was an annual event at Peine, nearby, which the Germans entered with great zest using early Porsches and various home-made Volkswagen conversions, and it seemed to me that the old J4 would be ideal for this type of event.
I advertised for a J4 (including in Motor Sport), but the few replies revealed only modified J2s or similar. However, one reply led indirectly to a C type which was dilapidated but completely original, and as the C was only one stage behind the J4 in development terms I bought it. All the C engine/transmission features were identical to J4, but steering,/braking and some bodywork aspects were behind. This was the “unblown” model, an in the subsequent rebuild I converted it to the “blown” spec by getting hold of a No 7 Powerplus and the associated reduction gearbox.
The rebuild was completed in time for the 1950 Peine event, which it was leading on the penultimate lap when put out by a broken crank! It gave a lot of fun in other minor races and trials in Germany, including the following year’s Peine event, when it was again leading half-way through but went out with a broken con-rod.
The car was able to achieve a maximum speed of 95 mph on alcohol/benzol, but the steering tended to weave, for unlike the J4 it had no divided track-rod. Furthermore the fin brakes were nowhere near as effective as the J4 12in jobs, and were juddery and inclined to overheat. A further weakness was the horizontally-mounted petrol tank which was affected by frame flexing, and kept leaking in spite of rubber mounts.
I set about uprating the brakes to the 12in standard, and also found a No 8 Powerplus which brought the top speed up to a mean 101mph — but another posting forced me to sell the car before I could get down to converting the steering to match. I had entered it for some VSCC Silverstone events in 1952-53, but as usual I retired, with broken cranks, rod or crown/pinion. I did manage a third place in the Welsh MC event at Fairwood in 1952, however.
The C is now in USA, stripped to the bare bones, and I hope the resultant rebuild will one day make it look and go like the J4 in Lubeck still does.
The equivalent exercise nowadays would consist of converting something akin to a 5TL Renault into a GT Turbo, or a Ford Escort 1.3 GL into an RS Turbo. My bet is that it would be nothing like as difficult, and relatively much less expensive. In the old days, for example, the Ambrosia crank for the MG cost £37, and the Powerplus £75, today’s equivalent of about £750 and £1500 respectively. At a rough guess, the total cost of conversion, without labour, would then have been about £550, or £11,000 in modern terms. Yes, it is easier nowadays! DG