Volkswagen Golf GTI

Which classics still have the potential to get up and go? Paul Davies remembers the cars, the people… and how to make a classic hot car!

Before 1975, about the most family fun you could have on four wheels was provided by the Mini Cooper S, or perhaps the fairly new Alfasud. Then, along came the Volkswagen Golf GTi. At a single stroke, the small performance car book was re-written, creating a whole new breed of pocket rockets capable of running rings around most other real-world four seaters. Enter the Hot Hatch. With crisp styling by Italian master craftsman Giugiaro, the Mk1 Golf was conceived as a Beetle replacement and set new standards for small cars. At fi rst, the top model had a 1471cc motor, hanging on from the fi rst Passat saloon. Then, along came the 1588cc GTi, complete with fuel injection! With 110bhp, and 112mph top speed, the original GTi was an ‘homologation special’ aimed at motor sport, with production of 5000 units planned for recognition in the Group 1 category for racing and rallying. But, as soon as the boys on the ‘strasse’ got their hands on the thing, the men at Wolfsburg had to up the tempo on the production line, to deal with a runaway success. The Mk1 GTi carved itself a niche in motoring folklore, fi rst with the 1600 motor and then, from 1983, with 1800cc in the 1.8 litre Mk2 Golf Gti, which many regard as the better all rounder – witness the number you still see in daily use. Ultimately and inevitably, to keep up with the opposition, the eight-valve engine was superseded in the hot-car world by a 16-valver, packing 139bhp. Here, though, we’re looking at just the two valves per cylinder car. It had to come in this Hot Car Classics series; there was no way the Golf motor could be ignored. But, in a way, it’s a bit boring. Talk to anyone who knows and they’ll tell you that there’s no one thing that makes the eight-valve VW motor outstanding. It’s just that it does everything very well, and will take all amount of tuning in its stride.

Get One Now

They’re out there to be bought, but you need to look hard to fi nd the real quality cars. The reason’s quite simple – once you’ve got yourself a good Mk1 GTi, chances are you’ll never get rid of it. Basket cases, some LHD, can be as low as £1000, but expect to part with £5k for a good example and up to £10k for a concours car. Specialists, clubs and internet sites such as Pistonheads are the places to start looking.

Hotting One Up

There are just two basic blocks to consider, best known not by their sizes but by the cars; the 1588 cc Mk1 and 1781 cc Mk2, although the larger unit was available in the Mk1 body at the end of the model’s life. Although there’s a distinct family resemblance, the 1600 and 1800 motors should be treated separately, since few major parts are interchangeable. The 1800 unit has a taller block to accommodate the longer-throw crankshaft that gives the engine its greater capacity. Faults rarely occur with the block, as long as it’s well cleaned at any strip down. Any problems are likely to be down to poor maintenance rather than structural failings.

Ditto the crankshafts, which like the rest of the internals, are good quality material and pretty well balanced on production. Standard pistons are also fi ne for a road tune engine, as are big-end bolts, but reusable ARP super-strength type should be fi tted on race engines. While the 1600 engine is considered preferable for a higher revving engine, on account of the shorter stroke, the 1800 unit delivers much better mid-range torque. But, a further increase in capacity is well worth the effort. As a 1.8 (or even a later 2.0 litre) will fi t into a Mk1 Golf engine bay without any problems, the 1781 cc unit is the starting point for bigbore conversions. With standard (86.4 mm) crankshaft and the block bored to accept 82.98 mm diameter pistons, the capacity becomes 1.9 litre (1869 cc). A full 2.0 litre (1964 cc) unit can be obtained by using a 92.8 mm throw crank and 82. 5mm pistons, both straight from the VW-Audi parts bin! Specialists, such as TSR, also have a 2.1 litre (2066 cc) conversion, which sees the 82.5 mm pistons combined with a 95.5 mm throw crank and fi tted in the 2.0 litre block used in later Golfs and various other VW-Audi models. It’s torque rather than out-and-out horsepower that makes the big-bore engines ideal conversions, with the 1.9 litre offering a increase of around 10 per cent over the 1.8, and the full 2.0 litre delivering an additional 20 per cent. The eight-valve cylinder head used in the Mk1 is certainly not rocket science, with the eight ports (four inlet, four exhaust) on the same side of the alloy casting. So it’s not a cross-fl ow design, but the post 1985 16-valve head is cross-fl ow, as is the 8-valve used on the Golf Mk4 and later models. Eight-valve 1600 and 1800 heads are not interchangeable, the smaller capacity engine has a head with flat surface, and the combustion chamber in the piston crown, whilst the 1800 has a chambered head. However, it is possible to fit the later crossflow head to earlier blocks if you wish. Like v i r tual l y al l engines, wor k on the cylinder head can see a useful increase in power. A fi rst stage head should gas fl owed with modifi ed standard size valves and valve seats, whilst a fast road or track engine needs further porting work, combined with bigger inlet and exhaust valves. Any high power engine should have 40mm inlet and 35mm exhaust valves fi tted, compared with the 38mm inlet and 31mm exhaust of the standard unit. On the induction side of things, the Bosch K Jetronic system fi tted to the 1600 engine is pretty crude by today’s standards, with continuous fuel fl ow and not all that much in the way of electronic management. The Digifant system used on the 1800 is more advanced, with electronically phased fl ow, but in both casesthese are not suitable for ‘chipping’. Very careful setting up of the standard 1600 and 1800 injection systems will be suffi - cient to cope with engine upgrades intended for road use, such as modifi ed cylinder heads or camshaft changes. An easy tweak for Jetronic engines is to fi t the throttle body assembly from the Audi 80 fi ve- cylinder engine, with larger secondary butterfl y. This will make any 1.6 more responsive, as well as adding three to four horsepower, but it’s not a straight bolt-on as a modifi ed inlet manifold is required to smooth the gas-fl ow over the ‘step’ between the (larger) throttle body and the inlet manifold’s ports. While careful attention to the standard injection systems can be good for up to 200bhp, a competition unit should move to either a twin Weber DCOE carburettor set up or an injection throttle body kit, which will then require a suitable management system, such as Motec or Emerald. In fact a throttle body assembly is really only for competition purposes. A camshaft change is benefi cial when fi tted along with an uprated cylinder head and exhaust manifold, although it’s not a good idea to go too mad on a road engine. Mk1 engines had solid tappets, while later 1800 units used hydraulic lifters (perfectly OK for road tune engines) to operate the valves.

Double springs are standard on all models. A decent exhaust manifold is a must with this engine and can provide up to 12bhp additional power, depending upon the engine specifi - cation. A 4-2-1 system is preferable for a road engine, where mid range power is required, while a 4-into-1 system suits a higher revving engine. Of course, you could just swap engines to join the power race. 1.8 and 2.0 engines fi t into Mk1 (1600) bodyshells without too many problems, and much more up-to-date motors, such as the 1.8T four and the VR6 will also fi t into earlier models. The Corrado G60 unit is also a nice engine, but take note that you can’t just bolt the G-Lader supercharger unit onto a GTi motor. As well as all the relevant manifolding and drive pulleys, you’ll also have to change the pistons to bring the compression ratio down to an acceptable level. Anyone contemplating playing with the G60 should also consider that the supercharger is quite likely to be somewhat knackered by now and deserving a full re-build. Mk4 Golfs of course came with VR6 power. It is possible to slot one into an earlier bodyshell but, like the Corrado unit, you should consider it as a complete unit transplant including, in this case, the transmission.

Handling The Power

On the handling front, the little VW responds well to all the usuals: Eibach can supply both springs and anti-roll bars of varying specifi cations, whilst Boge and Koni have sports-spec dampers for the car. The Mk1 Golf was blessed with disc brakes only at the front wheels and it was 1998 before discs appeared on the rear of the Mk4 Golf. Mk2 cars had increased diameter discs (256mm over 239mm) and you can buy upgrades for the Mk1 right through to vented discs of 325mm and you can adjust the ‘slack’ brake pedal on RHD cars. Finally, don’t forget the point of contact with the road. Any car that’s been lying around for some time will, doubtless, have tired(!) and outdated rubber. A set of the latest, perhaps coupled to a modest increase in wheel width, will work wonders.