Mods and Consequences

Originality is still king, but careful modifications are still well worth doing

Volvo P1800

The Volvo 1800 occupies an unusual corner of the classic car world, being enigmatic, yet widely recognised. It’s very usable in standard form, but even more so with a few mods.

The first of these stylish coupés were made in 1961 by Jensen. Known as the P1800, there was a twin-carb 1.8-litre engine fitted, as seen in the Volvo Amazon. Within two years production had moved to Sweden and the model was known as the 1800S (for Sweden); the first 2000 cars are P1800Ss feature the ‘cow-horn’ bumpers carried over from the Jensen era. A 1986cc (a 2.0-litre version of the 1.8) engine was fitted from 1968, then just a year later the carburettors were swapped for Bosch fuel injection. These models are known as the 1800E, the E denoting Einspritz, or fuel injection. All 1800s featured a four-speed manual gearbox until 1971, but a threespeed auto was introduced in 1972 just before production ended, to keep US buyers happy. An 1800 shooting brake was also introduced in 1971, called the 1800ES, but this was killed off in 1973. These cars are much less sought-after than the coupés, so if you’re going to make major modifications you’re less likely to decimate the value of your Volvo if your starting point is an 1800ES.

Most people don’t make major changes, though; they incorporate some sympathetic upgrades that improve their car’s usability without changing the appearance. The most popular upgrade is to replace the B18 1.8-litre engine with a B20 2.0-litre unit, because it’s a straight swap. You can increase the B18 engine’s capacity to 2.1 litres without compromising reliability – you can go as far as 2.4 litres with the B20, depending on the block used, but at this point you’re in danger of compromising reliability.

Alternatively you can slot in a B20E or B20F unit, which in standard (injected) form will push out 124bhp or 115bhp respectively. Originally fitted to the 1800E, 1800ES and 140 GLE, these engines can be bored out to 2.1 litres and with standard tuning mods including the fitment of a pair of SU or Weber carburettors, it’s possible to coax 180bhp out of it.

CHANGE THE WHEELS £150+ All 1800s came with steel wheels, so many owners fit alloys. You’re limited for choice because of the PCD and offsets. Minilites are popular along with Cosmics or Wolfraces, allowing you to go from 4.5J to 5.5J with tyres up to 195mm wide. FIT BETTER SEATS £200+ The seats in the coupé are comfortable, but those in the 1800ES are even better because they have an integral head rest. ES seats are sometimes fitted to a coupé, but with so few shooting brakes made, they’re getting hard to find. FIT A A STARTER BUTTON £25+ The 1800’s soft metal keys often break in the ignition barrel, which incorporates the coil. The fix is to convert to a conventional coil and ignition switch, or retain the existing set-up and fit a starter button, using just the first setting of the barrel. UPGRADE THE SUSPENSION £200+ Don’t lower or stiffen the suspension too much or you’ll ruin the ride. Slightly stiffer springs are worthwhile and polyurethane bushes will sharpen things up; an 1800ES rear spring reduces wallowing, as does an IPD rear anti-roll bar kit. TWEAK THE FUELLING £2000+ All non-injection 1800s came with twin SU or Stromberg carburettors. Swapping to Webers isn’t a DIY proposition as the steering column gets in the way on RHD cars, so you have to buy special manifolds or tilt the engine. FIT A BIG VALVE HEAD £200 Fitting a big-valve head allows the 1800 engine to breathe more easily. Find a fuel-injected 140 head; you can stick with injection or blank off the injectors to fit carbs. Using the 140 cam brings more mid-range torque and 130bhp. INSTALL AN ALTERNATOR £50+ B18-engined cars made up to 1968 got a Bosch dynamo; later B20-powered cars got an alternator. The dynamo is reliable and up to the job, but some owners swap to an alternator and its control box, usually taken from a 140.