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T H E   2 . 0   T W I N   S P A R K   E N G I N E

The GTV Spider's 1970cc four cylinder engine develops 114kW (155hp) at 6200 rpm and 186Nm at 4000. An interesting engine design, the DOHC, 4-valves-per-cylinder engine features twin balance shafts, two plugs per cylinder and variable camshaft timing. The head is alloy and the block cast iron. The spark plugs are not fired simultaneously as might be imagined. Instead, the second plug (offset within the chamber) fires 360 crankshaft degrees after the main, centrally-mounted plug. This spark at the end of the exhaust phase reduces the emissions output. The inlet camshaft phasing is controlled by the ECU, being altered by up to 25 degrees to give full overlap from as low as 1800 rpm. Ninety percent of peak torque is available from 2500 - 6200 rpm.

The Bosch Motronic M2.10.3 management system controls the sequential injection, ignition coils, knock control, EGR, camshaft timing and idle speed.  Other tech highlights of the engine include hydraulic tappets, a water/oil heat exchanger, cast alloy sump and eight-weight steel crankshaft. Backing the mill is the 5 speed trans with a 3.562 non-LSD final drive. The gearing is short, with fifth a 0.946 ratio.

The engine is an absolute honey. Superbly responsive, the flat torque curve means that there is always performance on tap. With 114kW and 1370kg to haul around, the Spider is no road burner (Alfa claim 0-100 km/h in 8.4 sec. with 2 adults + 20 kg), but performance in any situation is always competent. In fact it's often better than competent, the low gearing and creamy-smooth engine making the power just so useable, whether you're exiting a corner in second gear at the 7000 rpm redline or just cruising in fourth with the top down. This is one engine that shows that Alfa still knows how to make a fours cylinder engine that are amongst the best in the world!

The Spider uses MacPherson struts at the front with lower wishbones and an anti-roll bar. Rear suspension is sophisticated, with the multi-link design anchored to a die-cast alloy sub-frame. The rear suspension incorporates some passive rear wheel steering and is designed to hold the wheels vertical in all cornering conditions. The front suspension uses just over one degree of negative camber, while the rear makes do with half of a degree. To the naked eye it looks to be more than that, though. Steering is by speed-sensitive rack and pinion with just 2.2 turns lock to lock. However this figure is a little deceptive because at 10.8 meters, the Spider has a large turning circle, slowing the actual steering response.

The GTV/Spider chassis
When the current GTV/Spider project began, the instruction's of Paulo Cantraella, Chief Executive Officer, Fiat SpA. were plain and simple - No compromise, especially in the area of roadholding, handling and responsiveness - the latest GTV/Spider had to be magnifico, nothing less was acceptable.

As a result the GTV/Spider boasts one of the most sophisticated and radical suspension systems of any car in the world.

The front suspension utilises a fairly conventional set-up that comprises MacPherson struts, off set coil springs, lower wishbones and an anti-roll bar. But it is at the rear that Alfa's engineers have established the unit that accounts for the car's limpet-like grip on the road.

The independent, multiple arm rear suspension comprises quadrilateral geometry with an upper triangle, double lower arms, coil springs and anti-roll bar secured to a light alloy subframe which is, in turn mounted onto the vehicle's monocoque body.

The design of this geometry, and the fine tuning of the suspension bushes, is such that in the initial stages of a turn, the centrifugal forces create a small 'rear wheel steer' effect in the opposite direction to the way the front wheels are being pointed. Then, as the centrifugal forces build up through the corner, the rear wheels start steering in the same direction as the front wheels. The result is a more positive 'attack' into the first stages of cornering and increased stability in the later stages.