Engine
The Engine is based on the 1.6 16v engine found in the Corsa, Astra & Vectra models. We have used the cylinder head from the Corsa GSI engine (1992/1993) this head has slightly larger inlet ports than reduces the amount of port work required. We have designed new valves to allow the engine to breath at higher RPM. The head diameters have been increased on both inlet and exhaust, stem diameters are smaller at 5mm. The valve guides are replaced with a bronze version and new larger valve seats are fitted to accommodate the larger valves.

The Steel Crank been redesigned and now weighs in at approx 10Kg. We have managed to make the piston smaller and more compact (254g complete with rings & pin). At the same time the conrod has redesigned and also made lighter (384g), its length has been increased to 135mm to help reduce thrust loads.
Cometic Gaskets have produced a metal laminated head gasket for us to help with high compression high output engines. These have had produced in 3 thickness 1.3,1.7,1.98mm and for bore sizes up to 82mm.

Cylinder Head
We have designed larger Inlet and Exhaust valves with a diameter of 32.50mm and 28.50mm. The overall length of the valve stem has been increased to accommodate a greater installed valve spring height. The stem diameters on both valves have also been reduce to 5mm. The head has been completely reworked to take advantage of new components, with larger valve seat seats and new valve guide design.

New Camshafts have been designed for this season this has flattened the torque curve so the engine delivers smooth power from very low RPM with no dips in the power curve all the way to the rev limiter.

The MBE 970 ECU has been used to control the fuel & ignition. The engine uses 8 injectors to deliver the fuel. 4 in the inlet manifold below the butterflies and 4 in the carbon air horns inside the air filter. The lower injectors are used supply fuel at low RPM and low throttle openings, as the engine speed throttle opening increases the lower injectors are fade out as the upper injectors increase there fuel delivery.

The lower injectors needed for rapped throttle response and slow gas speeds. Where as the upper injectors being further away give the fuel more time to mix with the incoming air help the engine to produce more power.

The ECU controls 4 separate direct ignition coils mounted on top of each spark plug this eliminates the need for HT leads reduces weight and less components means fewer things to go wrong. The MBE970 not only controls the engine but may other functions as well. It is able to turn the alternator off an on to reduce BHP losses. Launch control which in its latest form has 8 different maps that can been set-up to control the Revs for up to 8 seconds from the start line, the driver can select 1 of 8 launch sequence even on the start line with an adjustable knob before beginning His or her start. The MBE970 system has many other functions available included Radfan control, Electric water pump control, Power shift (or Full throttle shift), Wheels speed less traction control (only suitable for sequential gearboxes), as well as output you configure to suit your own needs.

Westie on the Rolling Road December 2005
As Steve Greenald of Race Engine Calibration / Track n Road writes:

One of the most impressive car/engine combinations recently tested was the SBDevelopments Westfield 1700cc Vauxhall Ecotec. When Steve Broughton told me he expected in excess of 240 BHP I'd been more than a little sceptical. Contrary to popular belief only a handful of modified 2 Ltr XE engines make this sort of power.

As another example of SBD knowing their product, this amazing engine that revs to over 10,000 RPM produced a clean power run straight away of a healthy 241 BHP and 148 Ft Lbs of Torque. The generally accepted maximum that can be expected from any naturally aspirated engine is between 85 and 95 Ft Lbs of Torque per Litre of engine capacity. At just under 90 Ft Lbs / Ltr this engine is approaching F1 standards of performance.

The Rolling Road, in Rainham, Essex where the power run and remap was done is a collaboration between Steve Pitcher (Track n Road) and Steve Greenald (Race Engine Calibration). Between them they have over 60 years experience with performance engines. When Steve.P. decided to upgrade his Rolling Road facility 4 years ago he invited Steve.G. to move his 400 BHP Schenck engine Dyno from Ilford where he'd operated since 1984, to share the premises at Rainham. They in fact built 2 Engine Dyno Cells and hope to have Steve P's freshly reconditioned 800 BHP Froude machine running mid 2006.

The Rolling Road is a superbly accurate and repeatable German manufactured TaT CH2 machine, 1 of only 4 made to date. It's 1200 BHP single roller technology combines with a 4000 Nm retarder which caters for serious mapping work as well as inertia only power runs.