Blimey! All of a sudden everything’s gone a bit tunnel vision, a bit fuzzy round the edges. This thing really is seriously ballistic, the straight is fast disappearing, the engine howling at 9000 rpm. Time for the brakes and a blip down into third for the Chobham banking. Grip, serious grip. The momentum pushes you up the shallow bank as the car keeps on accelerating. Out of the corner, floor it. Engine pick-up is instant and the revs whip round to 8500 rpm. Back into fourth, flat out at 120 mph thanks to sprint gearing.

Crikey! Steve Broughton’s Vauxhall propelled Westfield-come-rocket-ship has changed a bit since I drove it last year. For a start it’s no longer a road car. Free of the restraints of the highway, Steve has binned things like lights and windscreens, heater and road tyres. This is a fully fledged racer, and a winning one too. In case you didn’t know, Steve Broughton is the SB behind Vauxhall tuning specialists SB Developments. Steve knows a bit about tuning Vauxhall 16-valve engines, and the Westfield is a bit of a rolling advert for his undoubted talents. The 270 bhp engine fitted is one of Steve’s ultimate spec engines. But it’s not just the engine that’s impressive. It’s quite obvious that Steve is just as adept with suspension geometry and general car set-up, not to mention aerodynamics and even ground effects.

Steve runs in the CCC Speed Championship and has designed his Westfield to run in the Sports Libre class. That means he’s up against some very quick Mallocks which have serious downforce dynamics, if not the ultimate grunt of this Westfield. This is only Steve’s second season, but he’s not experiencing much of a learning curve given that in his first season he won the overall Southern Championship And that was despite swapping between the road-going kit car and sports libre classes.

This year’s car is all new and features a whole load of trick bits, and improvements over last year’s car. For a start the chassis is both lighter and more rigid. The standard Westfield chassis is designed to take a variety of engines and for that reason the front is comparatively open. There is plenty of opportunity to stiffen it up with extra tubes, and the factory agreed to modify a lightweight racing chassis to Steve’s specification. He has also taken the opportunity to have some extra tubes added to the rear. The result is a complete lack of flexing and an incredibly stable ride. The latter is also helped by Westfield’s new wide track front suspension set-up.

Naturally the suspension is fully rose-jointed. Steve favours Avo dampers and has had some specially valved to his own specification. He claims that he has still to properly sort out the geometry, but I couldn’t feel much wrong with it! The sticky 14in Avon slicks give incredible grip but progressively so. You can really push into a corner and feel the car start to give. It is confidence inspiring more than anything, knowing that its not suddenly going to come round and bite you on the bum!

But more impressive, of course, is the sheer oomph that Steve’s engine building skills provide. Steve wasn’t actually planning to build a 270 bhp motor, it just kind of happened. This sort of power, lest we forget, is the kind of grunt that 2-litre Touring Car engines used to produce a few years back. When utilised to power a mere 480kg’s of Westfield, it’s downright explosive.

The secret is some lightweight internals that allow the engine to really rev, coupled with Steve’s tapered throttle body injection set-up and a heavy breathing cylinder head. A mere brush on the throttle is enough to send the rev counter blipping to the red zone, the engine is seriously responsive. In fact, Steve advises not to change down a gear mid-corner, as the resulting engine de-acceleration will spin the car round.

Steve had a steel crank specially designed and manufactured by Doug Kiddey, who also makes the cranks for the Mercedes/Ilmor F1 engine. This is a massive 25% lighter than previous efforts. This turns ultra light Arrow con rods and specially made Omega race pistons. As this is being written, Steve is out of stock of all these goodies since the TWR Formula 3 team scooped up everything he had, and since doing so have started to win some races!

Surprisingly, despite such power from just four cylinders and two litres, the engine is amazingly tractable and can be teased off line with just a few revs (should you want to). Ah, the wonders of engine management.

Typically, the car bristles with innovative touches. Under the nose a front, F1 style, splitter cuts through the airflow. Does it work? Well Steve’s F1 mates tell him that it will make some difference. Likewise the rear ground effects undertray, properly moulded from fibreglass (aluminium lash-ups tend to distort when the air starts rushing around them), should in theory help keep the car glued down. If you’re interested, Steve can offer both these items to fellow Westfield racers or, indeed, road racers.

Having driven a few Westfields in my time, and being the owner of a race Westfield, I can say this is probably the best handling and dynamically impressive one I have ever driven. Above all, despite its rampant power delivery, it is easy to drive. And when you can concentrate on the driving rather than wrestling with the car as it tries to catch you out, then that is half the battle.