There are some truly exceptional engine tuners in the UK, and it's an area we're truly blessed in and among them are some top companies such as Scholar, QED. Minster, Mountune, Raceline, there are some real greats of the engine scene there. Right up at the top of the tree is SB Developments founded by Steve Broughton 20-years ago this year. Steve, formerly worked at British Aerospace in Kingston-upon-Thames, where he developed a keen interest in motorsport, along with his friend Richard Hulbert, a keen rally competitor. 

 

Richard eventually got a job working in Saudi Arabia & had to give up rallying, but Steve decided he wanted to have a go at it himself, so built a Vauxhall Chevette & took up where Richard left off. From that moment on he was hooked and decided to carry on. Several years later when he left British Aerospace, the motorsport bug had really and truly bitten. Actually he spend the next 11-years working for an automotive general repair business until he decided to set up on his own, from a shed in his back garden.

 

Although known nowadays for supply of tuning kits, back then Steve specialised in dampers and camshafts working with the likes of Koni and Kent Cams, until one day a chap called, Roger beard, suggested to Steve that he should build him an engine, a potent Vauxhall XE, complete with a 'happy days' budget of £10,000. Roger, a hillclimber, usually running in the midfield reckoned that Steve could build him a winning engine, an XE is around 150bhp in standard guise and is a reliable, tough engine but the customer definitely wasn't expecting the 250bhp that he was presented with, although Unsurprisingly, as you'd expect, he was delighted, especially when he started winning!

 

This brought Steve to the attention of the late, Roy Lane, one of the UK's top hillclimbers, and from there things sort of grew very quickly for Steve Broughton and his SB Developments operation, forcing a move to a unit located on an industrial estate in Surbiton.  

 

Around the mid-nineties Steve was seemingly never out of much-missed magazine, Cars and Car Conversions known to all and sundry at Triple C and his reputation continued to grow, aided by lots of motorsport successes with Steve himself enjoying notable results in the British Sprint Championship & winning the BARC CCC Speed Championship. This encouraged many Westfield owners to turn to SBD for engine expertise, culminating in Mark Smith winning the WSCC Speed Championship overall.

 

 

These days Steve can supply a set 'menu' of tuning kits and performance parts for the XE, with a stonking 290bhp being the most powerful on offer. There's no rocket science involved, no witchcraft, just a keen eye for detail and an inquisitive mind. Anyone can build a grenade engine that detonates after a few miles, but in the real world what's ok for an F1 qualifying special isn't good for an enthusiast who invests his hard-earned cash into a performance engine for his sportscar. He wants horsepower, but he also wants value for money and of course reliability.

 

Steve is very methodical about what he does and you won't find false claims that can't be backed up on a dyno. Other unnamed engine builders often can't get anywhere near his power outputs, while several other companies feature SBD parts either anonymously or re-branded. That should tell you a lot.

 

In 2004, SBD turned their attention to the Ford Duratec reconising its appeal and its potential for tuning and the fact Ford had launched the unit to be a long-term engine with an extended production life. It wasn't very long before Steve had come up with a range of Duratec kits, culminating with a 2-litre range topper delivering a phenomenal 307bhp, which must be the most powerful commercially available normally-aspirated 2-litre in the world, some 61bhp more than the equivalent production car record holder, the Honda S2000's F20iVTEC.

 

Then came the addition of Suzuki Hayabusa kits to the SBD range partly driven by demand, partly by Steve's recognition of its potency and topping the SBD Hayabusa line-up is a stonking kit that features a jewel-like Rotrex supercharger. 

 

Another aspect of the SBD business is their close association with MBE, founded by Jeff Moore, Steve Baker and Jerry Elphick, one of the UK's leading manufacturers of mappable ECUs dealing primarily with top end pre-production work for mainstream manufacturers although their specialist aftermarket product range is looked after by SBD. This means that for the specialist car enthusiast Broughton's company can be a one stop shop covering your engine and its management requirements, although even if you have an ECU from Omex, DTAfast or Emerald M3D for example, SBD will still happily help you with an engine kit for XE, Duratec or Hayabusa, although be aware that if you an MBE ECU with your SBD engine kit, you won't be faced with additional cost of rolling road time to set it all up. 

 

Typical SBD Vauxhall XE Engine Kit Package (292bhp) 

SBD developed their TP290 kit over several years, and it gives a very high output with a strong, smooth torque curve. It is now one of the company's most popular kits and has seen use in rallies, circuit racing and sprinting.

 

They have designed it to be a relatively simple kit to build and have consciously tried not to use too many 'exotic' components, which means the maintenance cost of this engine is manageable. The headwork included uses a larger valve size of 35mm inlet and 31mm exhaust with standard size valve guides. The MBE9A4 comes pre-programmed and ready to use, however with this level of specification they recommend a mapping session to fine-tune the engine. The kit includes a wasted spark wiring harness and it has the following parts; new design throttle body, steel rods and Omega high compression pistons, a dry sump system and high specification camshafts. The kit also contains the necessary components to achieve 290bhp with a few extra safety features as standard e.g. up-rated flywheel bolts, main cap studs, head studs and uprated bearings.

 

SBD favour a taper throttle body set-up over a more conventional parallel body type. The company's taper throttles kit are made up of four single bodies (on a four cylinder engine), which is 66mm long tapering from a 48mm diameter hole at the ram pipe end down to 42.7mm at the manifold face with a 45mm butterfly in the middle.

 

SBD say that the main advantages of using a tapered singled body over parallel bodies and slides are that being individual can be perfectly set-up, while they have also found that the use of a taper that continues the shape of the ram pipe right through the throttle and manifold up to the valve has improved torque through almost the entire power band. Use of a 45mm butterfly with a taper has improved throttle response and they have carried out tests comparing a taper throttle with a slide throttle; both being of a similar size, as it is had been suggested to them that an intake system such as slide or barrel throttle systems would surely produce more power because there is no butterfly restricting the port.

 

Steve's back-to-back test showed virtually no difference in peak power at all, but the throttle response on the taper body system was significantly better than the slide system.

 

The peak horsepower from the tapers (with 45mm butterflies is better than they achieved in similar tests using 48mm parallel bodies or a slide throttle assembly.

  

I'm a big admirer of SBD and of Steve Broughton. he has always has the knack of obtaining reliable horsepower figures that can be back-up time and time again. He deeply analyses what he does and de mystifies what can be, let's face it, a black art. He uses real worked parts, recognises what each customer want and offers incredible value for money, and in this day and age, that's a rare ability. 

 

The SBD Team 

Key personnel at SBD, apart from Mr Broughton are Carole Torkington (16-years service), Kim Kingham (7-years service) and technician, Craig Sampson. Carole is a very capable sprint competitor, previously in a Westfield but more recently in the WSCC series in a Darrian T90 that she shares with her brother, Colin Early.

 

Meanwhile, Kim was also a very competitive pedaller, in a OMS single seater, until a serious accident a couple of years ago, put her out of action, from which she has thankfully made a good recovery. Although she doesn't compete anymore, her role at SBD is an important one and includes keeping the website up-to date.

 

 

Reproduced with permission of Total Kit Car Magazine