If you are considering purchasing one of these models, which it is hoped you are, as with any classic car, there are certain drawbacks in a vehicle that is close on 60 years since its design and manufacture. You need to do your homework and talk to current owners and/or join one or more of the enthusiasts’ clubs around the world that cater for this model, thereby gaining the required knowledge, understanding, chitchat and camaraderie surrounding these cars, which are also affectionately known as ‘The Tupperware Pig’. It’s a great car – try one, then buy one.
Although the body is glass fibre and that in itself doesn’t rot, there are areas that are prone to stress cracks, such as the boot (trunk) lid and the rear wings (fenders), caused by imprudent packing of the boot (trunk), and also at the front end around the nose section if the chassis front cross tube is in any way rotten.
There are within the glass fibre body certain steel inserts that may have rusted. The most crucial are located in the front nose section, either side of the radiator. They secure the front end to the front cross tube on the chassis and if in good order prevent the front end from flexing which in turn checks the bonnet (hood) from flying open. Further steel strengthening inserts are in the bonnet (hood) catch opening area; either side of the engine bay by the exhaust manifolds and the seat runner fasteners. On B&C spec cars there are steel inserts where the hoop brace within the cockpit passes through the glass fibre floor that is bolted to the chassis outriggers; and behind the front seats where brackets are secured to the outrigger uprights in the inner rear wheel arch (B posts).
The chassis itself is strong, but again is prone to rust in certain areas, the front cross tube – as mentioned previously – that carries the steering components; the front suspension turrets; the outriggers; the rear front spring hangers – all easily rectified. Also, note that some standard steel wheels fracture (hair line cracks) around their fixing holes, no doubt caused by an overzealous air torque hammer gun operator at the local garage/tyre shops.
The engine is, as said earlier, the jewel of the car and the most common problem encountered is with cylinder head waterways – corrosion – easily repaired, where perhaps over time, the incorrect balance or lack of inhibitor has been used. One bonus however, engineered into the heads from the engines inception, is the hardened valve seats to cope with the low octane petrol (gas), that in the late 1950s was the only fuel available in certain countries where the SP was being marketed. If however you wish to modify the engine, it can take it, and it has been done – Russ Carpenter has stretched it to 1400bhp and then some!
As time and development has progressed in the automobile industry, so the SP has benefited retrospectively, whether it be: advanced cooling systems, anti-roll bars, braking enhancements, chassis, electrical, electronic ignition, lighting, oil filtration, steering, suspension, transmissions and tyre technology, all so that we are able to maintain and enjoy our cars in an up to date manner, if you are a purist however there is no earthly reason why you should change anything – save the tyres!