AN MG TALE

I'd always rather regretted swapping my TF l250 (now owned by club member John Buxton) for Geoff Roud's Variant (23 ft keeler, not the car). Not that we didn't enjoy the boat. We owned it in fact for eight years, did trips as far afield as the Bay of Islands, and made many new friends through Richmond Yacht Club.

A lot of time and effort had been put into rebuilding the car. It had introduced me to the MG Car Club back in 1974, and we'd had a great deal of fun in it. I'd considered restoring another TF, but on checking, found that although there were suitable cars about, people seemed to think they were made of gold. They were asking what seemed at the time, to be astronomical prices, for what were really basket cases requiring rebuilding from the ground up. We didn't have too much of the folding stuff at that stage, and I was discussing the problem at morning tea one day with some of my colleagues at work. Now I'm not sure who it was that actually said, "Why don't you make one" but that was how it all started back in February 1980 or thereabouts.

Initially, there were three of us involved who were keen on the idea, and we spent a considerable amount of time, deciding just how we should go about it. Working where we were was a bonus, since it meant access to metal working equipment and machinery for making parts. Between us we had a considerable range of skills, and this would be a chance to exercise and improve these. Motor and gearbox etc. would come from a vehicle of about the same vintage and after much debate back and forth, we settled on an MG Magnette as the donor car. There were probably three main reasons for this.

1. It would contribute all of the major mechanical components, which would of course be genuine MG. These would include the later BMC B Series engine and gearbox, parts for which would be a lot easier to come by, than the original T Series units. Since we expected to produce a car of much the same weight as a standard TF, the 1488 cc engine would give comparable performance to a TF1500.

2. The track width of the Magnette was only one inch wider that the TF and we could accommodate this quite easily in a TF body. Although the wheelbase was longer, this would not present any major problems, since we had to build a chassis anyway.

3. There were quite a few Magnettes going rather cheaply at that time, and in fact the dearest one we purchased was only $450. We must have started a run on the market, because suddenly the price of Magnettes seemed to shoot upward to around $900 or $1000.

The first major area to be considered was the chassis, which would be the backbone of the car. We decided to use the complete Magnette front suspension arrangement, incorporating the front cross member into a fabricated chassis. This would provide, we hoped, a considerable improvement on the original TF suspension system. It incorporated a standard double wishbone and coil spring with telescopic dampers, as well as upper and lower tie bars back to the chassis. One problem to overcome was that the Magnette was around 4cwt (200kg) heavier all up than a TF. The engine in the Magnette is mounted partially over the cross member, and hence the whole system, and in particular the front suspension, would be considerably stiffer that the TF.

Knowing how my original car handled, and after having seen photos of it cornering at Bay Park, I'd always felt that the front suspension on the TF wasn't really stiff enough. Even so, the Magnette suspension would probably be too stiff, and certainly the ride height would need adjustment by resetting the front coils. It was quite easy to measure the weight distribution on each wheel by incorporating a simple pressure gauge into a small hydraulic jack, and the large tensile/compression tester at work made it very easy to check the spring rates of TF versus Magnette. After checking the geometry and relative forces involved in each arrangement, and after much cogitating, we decided to go for simply re-tempering and resetting the Magnette coils by lowering the free height. By cutting down the rear springs, which were conventional semi-elliptic to TF length, and removing the second full-length leaf, we obtained approximately the same stiffness in the rear as the original car. In operation, the suspension is certainly stiffer that the TF in the front end, with much less body roll on corners, although still providing a comfortable ride.

The design requirement for the chassis then, was to incorporate the Magnette front cross member into a steel ladder type framework, which duplicated the TF unit, providing the required mounting points for a conventional TF body. This was made from 4" x 2" x 0.1" steel purlin sections with cross members and scuttle support bar from 1.625" x 0.125" heavy wall tube. Body support brackets etc. were made up from 0.100" flat sheet. The real TF chassis section reduces over the rear axle and down to the rear spring hangers, but for ease of manufacture, we maintained the same section throughout. This was to cause some problems later on, but by February '81, we had a rolling chassis.

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