An M.G. Magna Rebuild

M. D. Tooley describes his interesting M.G. with Opel I.F.S.

In June, 1943, my brother and I found an M.G. Magna (F-type) in an Essex breaker’s yard. The car was purchased for £18, which now seems an extremely modest sum, and was towed home. The back axle was in place, but everything else abaft the clutch was in a heap in the back of the car; an evening was spent merely sorting out this heap. Since the F-type Magna is a well-known vehicle, I do not propose to give any detailed description.

Rebuilding proceeded in the usual way by cleaning, repairing and replacing where necessary. In the course of this the rear axle ratio was changed from 8.43 back to its original 9.44. During this rebuilding process I decided to attempt to fit independent front wheel suspension. A “vertical” type was decided upon, such as Vauxhall, Singer, Morgan, Lancia, etc. Finally, an Opel front axle was found near Portsmouth and was brought home by air — a rare process, I believe, for the products of a breaker’s yard.

The front axle and springs were removed from the Magna and two brackets were bolted outside the frame, to which the fishplates, welded to the Opel axles, were bolted, the upper surface of the fishplates being horizontal, the bracket welded to the axle centre was removed by unkind methods.

Wheels presented a problem. The prospect of centre-lock wheels aft and pierced-disc, bolt-on wheels, with bulbous tyres forward, was uninviting. Finally, five new 7/16 in. B.S.F. studs were fitted to each Opel hub (at staggered intervals to miss the internal webs) and the inside flange of each M.G. wheel was drilled to fit; the hole in end of the wheel hub was closed with a bakelite cover. This arrangement proved satisfactory, and we have lost no wheels yet, also the projection of the king pin axis strikes the ground within 1 in. of the tyre contact point, thus preventing heavy steering and excessive wear. The front track is 3 ft. 10 in.

The brakes were next tackled. As I had already overhauled the M.G. rear brakes when the Opel axle was acquired, it was decided to convert the Opel brakes to cable operation. The hydraulic cylinders were removed and replaced by bearings to carry the brake camshafts from the M.G. Each brake shoe had to be lengthened by mild steel plates, riveted on. The M.G. operating levers and Bowden cables were used. I think that if I were to repeat this job I should retain the hydraulic operation, converting the M.G. rear axle by means of Wolseley “Hornet” bits.

Finally, the draglink was given two kinks, and its ball joint was fitted to a plate of extraordinary shape, which was attached below the near-side spring cylinder of the Opel assembly by means of studs and bolts in two directions and three different planes. This gave a ratio providing about 1 3/4 turns of the steering wheel from lock to lock; the diameter of the turning circle is 44 ft.

The body is by Jarvis and was in poor condition; in fact, the rear half was held on only by two small brass woodscrews (additional means of support have since been provided). The standard battery was removed from its position behind the rear axle and was replaced by one of more common shape, in a cradle fitted outside the frame behind the nearside front wing: here it is accessible and provides short leads to the starter. A new dashboard was made of cadmiumplated steel, the original instruments were fitted and a revolution counter, made from a speedometer, was added. The 6-gallon tank was replaced by one carrying 12 gallons, occupying the space where the battery was formerly fitted. Two large 16 s.w.g. steel undershields, with which the car was originally equipped, were omitted. The car now weighs 13 1/2 cwt., with almost equal loading on each axle; the Magna, with an M.G. 4-seater body, weighs 19 cwt., and it is felt that this reduction is the main reason for the low petrol consumption, which works out at an average of 34 m.p.g.

When we examined the engine we found that it had been fitted with cylinder liners, new pistons of standard size, a new crankshaft and new main and big-end bearings. It clearly had not been run since this work was, carried out. It is still being run-in and, for this reason, performance figures cannot be quoted; however, I assume that they will be about normal for this car.

The behaviour of this conversion is excellent. Roadholding is good and the steering is light and quite accurate, in spite of (or because of) the enormous movement allowed for the front wheels by the supple springing. Braking is good — there is no tendency to “wind up” the suspension, since Opel provides a brake-reaction link pivotted to the brake back plate. Unfortunately, the nose of the car is a little higher than is standard (the difference is 2 1/2 in.), but one becomes used to the appearance. I have cut away the wings, etc., so that the full beauty (?) of the device is apparent.

During the operations on this car I was much encouraged by the articles on Opels, by Anthony Phelps, and on Suspensions, by C. W. S. Marris, in Motor Sport.

This conversion may be applied with equal facility to J-type Midgets, and possibly (I am not sure of this) to later N- and P-type cars.

The car is now operated by my brother and is resident in Hatfield, Herts.