Dating from very late 1960s, The Porsche 914 is so much like most cars from about this era, the rust is your biggest worry. The Californian imports suffer much less, but the US safety bumpers are a turn off. Look just behind the front of the bumper, also around the torsion bar mounting on the body shell. Rust affects the headlamp box just below the pop up lamps; a blocked drain tube at the floor by the front boot means more problems. The front lid may have rotted as well at its rear most corners, because foam injected in to bracing members eventually gets porous and will hold water up against the metal. Replacing is more cost effective than a repair. Now, check the scuttle panel just ahead of the front screen, another common rust spot.
Check the rubber seals on the Targa roof also the quarter lights for any signs of leaks. Open up the doors to see that GRP roof section is able to be fitted / removed easily. If the door sills are weak the car might sag a bit in the middle, causing fit and finish issues. Outer covers on sills is a common quick cover up, but can conceal very serious structural corrosion, just make sure you prod about at exposed ends. Next lift the carpets up to look at the inner faces of the box-sections, check the floor very carefully where it meets for corrosion
Damp in the foot wells is very common; this leads to serious corrosion of the area of the floor about the pedals also where the floor section meets the centre tunnel. Sometimes a seized brake pedal is clue, it causes the metal spindle to rust and swell, and this then jams in the nylon bush mounting. Fresh air heater fan not working? This can fail as of cigarette ash has fallen through the ashtray. Exterior crap, like leaves can burn out the motor. The door bottoms always rust, so you need to check the shut face that carries the lock.
Engine maintenance side is pretty straightforward, but some cars from the factory had a fuel injection system, and most DIYers convert to carburettors rather than struggle with complexities and costs of injection. The experts say a properly set up injection system is way preferable to carburettors, but make sure you have tried it both ways before you convert a car. Dropped inlet / exhaust valves seem to be a weakness of these engines, much as other VW engine types of the period. The exhaust doesn`t seem to last very well, either. Although the transaxle unit is a robust Porsche unit, but the driveshaft’s fail, and the bolts do come adrift gearbox end.
Gear linkages on pre- 1972 cars are not the best, many owners convert to the very much-improved type introduced in the 2.0-litre models. A good precautionary measure is to thoroughly overhaul the whole braking system as well as the fuel lines when you take on a Porsche 914. The handbrake is actually built into the rear brake calipers, and quite often can seize. Note brake discs on the 2.0-litre model have a different off-set than those on smaller engined 914s, but aren’t interchangeable. Fuel lines will rot though – especially around the battery tray area.