Litre 4 cyl 16 valve

This model was the final development of the original 924 and is based upon the 944S2 with several significant changes. It was re-styled to incorporate some more modern 911 styling features (very similar the more recent 993) and the S2 based engine received a variable inlet camshaft-timing device to further increase mid range torque. Gearboxes were available in 4 speed-tiptronic and 6 speed manual versions.

Two versions were originally made available, the luxurious 968 and the contrasting light but somewhat crudely appointed Club Sport. Later a demand grew for a compromise between the two versions and the Sport version was listed, usually with a mixture of the best specifications of the other two. The Sport typically had 17-inch wheels (as originally fitted to the Club Sport and a favourite upgrade requested on many older 944's) and usually had electric windows and mirrors, adjustable seats and a sunroof. The modern looks and outstanding performance of these practical sports cars combined with the small number manufactured have increased demand and prices remain exceptionally high. With, great looks, brilliant performance and exceptional reliability, they may well enjoy cult status in the future.

The 968 Sport.

The 968 Sport.

It has a superb engine, similar to the S2 with improved torque. It still has potential problems with camshafts, belts and chains, (similar problems with 944S and S2). These will probably materialise after higher miles still (except perhaps for the Club Sport, which will usually have had a harder life and are often in poor condition) and these minor problems are easily avoided with proper maintenance and timely replacement parts.

There were also a few detailed changes in specification to the S2 that didn't really improve this model as much as expected. We have noticed many examples where the new fully automatic camshaft belt tensioner is on the verge of failing (through having become fully extended or seized to the pivot shaft or undoing the pivot pin which then fails through metal fatigue) which could cause serious engine damage. Fortunately the problem is avoidable with proper maintenance and attention to those areas

In an attempt to reduce the cost of replacing the expensive rubber damped clutch on the previous models, a dual mass flywheel was fitted instead (as had been reasonably successfully achieved with the later 911's). However -perhaps due to the less smooth power delivery from a 4 cylinder engine and greater individual power pulses (compared to a 6 cylinder 911) they do seem to start failing quite early in their life, causing a slight vibration on tickover and eventual rough power delivery. However, if this is ok, then clutch replacement is much less expensive and quick to achieve. Dual mass flywheels can be sourced at reasonable prices - if needed.

The 924S, 944 & 968 Engine range. As these have similar components and problems they are listed here generally to cover all models. They provide very robust engines provide superb power delivery, and long life. Failures are usually avoidable without huge expense and are predictable in most cases (following inspection by an expert), but failure in any one of the engine components can be expensive to repair and is best avoided. The engines are capable of well over 250 thousand miles (with proper maintenance), although with neglect they can suffer damage at anything above 50 thousand miles. The key is to allow an expert to carry out a few simple checks, which will reveal the condition of the engine - reliably. The main problems (which are quite rare or only occur after perhaps 80 to 120,000 miles) are: - Cam belts. The cam belt and balance shaft belt, although inexpensive to replace, once snapped can cause the valves to hit the pistons and this can result in the whole engine being lost. They should be checked during each service (replacements should be undertaken at least every 45 thousand miles). The rollers (and water pump pulley) around which the belts travel, are not externally lubricated but have sealed for life bearings and if these fail they can cause a perfectly good belt to snap with the resulting serious damage previously mentioned. A full investigation of these components should take place with any car that is new to the buyer and is as important as checking or changing the belts.

Oil cooler. The oil cooler in pre '89 and non-turbo engines is not an air-cooled system as with most high performance cars, but is like a small radiator fitted inside the main water jacket of the cylinder block. On earlier models, they were connected by red seals, which have a limited life and eventually leak. Replacement green seals have a much longer life. If they leak they enable oil under pressure to be passed into the water-cooling system as a brown sludge with serious damage to the engine a resulting possibility.

Head Gasket. As these all aluminium water cooled engines heat up and cool down the continual expanding and contracting, compresses the head gasket until after many years it can fail. This is usually noticeable by the car running hotter than normal, the level in the header tank always being at the low level and excessive pressure in the top hose. Left unattended, these faults can become serious.

Tappets. Light tappet ticking noises are not necessarily a problem and can happily be ignored providing they are not excessive (and sometimes the noise that sound like tappets actually emanates from the fuel injectors anyway). The 944, 2.7 models - seem to reach the point of ticking sooner due to increased - tappet to housing wear rates caused by the higher lift camshaft lobes.

Piston Ring Wear. The aluminium cylinder blocks on these cars do not have cast iron liners. Although the silicon nitrides that are cast in the mix provide a superb lubricating surface and long life to pistons, some pre '87 944/924S models (and many 911, 3.2 Carrera's) can wear out rings prematurely. This can put a deep score in the cylinder bore to cause it to be scrapped. If the engine on one of these models smokes badly on heavy acceleration at high revs, then the piston rings are probably nearing the end of their useful life. If this is left unattended they can break up into small pieces eventually turning and wrecking the cylinder bores. A puff of smoke when changing gear is commonly caused by old valve guide seals and is not necessarily serious.

Vibrations & Engine Mountings. There are four typical sources of vibration on the 944 (including the S, S2, Turbo and 968) engine. One is that the balance shaft belt has snapped, giving a fine vibration at low revs - up to about 2000 rpm. Clutch cush drive problems can cause vibrations throughout the whole rev range. A worn out -off side - engine mounting results in a harsh vibration on tick over which goes away with revs. The most common is caused by incorrectly fitting the balance shaft pulleys and inadvertently miss-timing the shafts.

911 (2 litre to 3.2 litre, 6 cyl to 1989). These 911's are completely different cars to the typical 944/968 range, for a different market. Being more noisy and less comfortable, with less sure footed handling, and a more old fashioned interior and driving position, they nevertheless do have a unique character and presence all of their own and consequently have a huge following. They are exceptionally exciting to drive. However, we have found it is usually uneconomic to prepare for sale, pre '83 models to our usual standards. We do not offer a full renovation service for very neglected - older examples because they occupy too much workshop space for too long. It will prove very difficult for a private buyer to find a reasonably priced, reliable pre 1987 911 that is not hiding expensive faults.

Although it was built to very high quality standards, it's very success held back it's modernisation and although it was probably the fastest and most exiting sports car of it's era, it does now seem quite old fashioned in it's interior and lack of extras. Never the less it does have a unique character and presence all of it's own. It provides even more image than a 944, seems more thrilling to drive but due to it's comfort shortcomings, it is probably more suited to occasional use and short journeys for those who can use something else for day to day use and the 911 for special occasions. This aside, the 911's thrilling engine note, 1st gear acceleration and head turning potential is second to none.

1979 911 SC 3.0 Litre Targa

1979 911 SC 3.0 Litre Targa

Early 1970's models were surprisingly fast and light giving excellent first gear acceleration and the drive and the sound of that superb 6 cylinder engine combined with the light weight and steering provides a unique experience that is always thrilling and satisfying. The later 3.2 Carrera did take a big step forward in beginning to modernise the interior and the fuel and engine management systems. The light hydraulic clutch and the G50 gearbox fitted in 1987, brought this version closest to being an acceptable drive by modern standards, but the performance of all models over the years, right from the 2 litre to the 3.2, was quite similar as gradual refinement increased the weight and increasing demands on emissions reduction required bigger engines but with gradually improving performance.

The 911 engine has long been established as a powerful and reliable unit with good power to weight ratio and torquey performance. Although older 911's tend to be used quite infrequently (which usually renders the engine internals comparatively unworn), the air cooling ducts and the integral oil cooler tends to clog with debris, while there are numerous places for oil seals to shrink with age and for oil to leak out.

Having a dry sump - some cars can - if left standing - fill the crankcases with oil causing smoking on firing up and causing oil to bypass the rings and fill up the exhaust system - but it can burn of with use. Initial smoking is therefore not always a sign of a badly worn out engine.

The heat exchangers are notoriously vulnerable and potentially dangerous and many sellers disconnect the air feed into the cockpit to disguise a fault by preventing fumes filling the inside of the car. Providing seals and gaskets are changed when needed and care taken re-setting the cam chain tensioners and positions, the engines will satisfy occasional use with moderate performance.

It is not uncommon to break a cylinder head stud on a 3.0 litre engine requiring expensive replacements. Because the engine needs removing to tackle most jobs, it usually pays to thoroughly overhaul it while it is out to avoid the expense of continuous removal as things go wrong, hence small jobs can grow to involve quite high costs.

The very early models had either two triple choke carburettors (which worked well but had no effective cold start requiring some patience) or mechanical fuel injection, which by now is becoming quite unreliable. They are light and had good performance with twitchy handling that took time to learn to control safely.

They do rust quite badly but there are plenty of specialists who will fully refurbish them - at a cost. They are typical of other sports cars of that age and have - what today would be regarded as - rather crude and basic interiors and controls. The introduction of K Jetronic fuel injection for 2.7 and bigger engines around 1974, improved the fuelling, starting and emissions (but is still crude by modern standards) and continued through the 2.7 - 3 litre Carrera 3, SC and Turbo.

We generally avoid buying anything prior to the 3.2 Carrera (unless it is a part exchange) because we have found that we often spent over £5000 renovating them to reach our standards for sale. We also prefer coupe's to targa's due to difficulties with water leaking in as the cars age. Even though the 3.2 models incorporate the improved Motortronic fuel injection, we still find that they often need engine rebuilds (for rings and seals) and new exhausts and clutches. The latter version with the G50 gearbox overcame the synchromesh problems of the earlier model and is a much better gearbox to use.

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