My only real disappointment with the first MINI Cooper when we got it in 2001 was how totally and utterly underpowered the car was. In my opinion the car should always have had a 2 litre model - the chassis could easily handle it! We quickly started to look for more power. What options existed for a cost effective, easy to install, reliable and substantial power gain on this car?

A large range of options were considered including:-

• Modular tuning package to including exhausts, cylinder heads, ECU upgrades,,, would be very profitable, but ultimately not the best option for most customers. We wanted an option driven by our enthusiasm for the vehicle not by our enthusiasm for profit! Charging £400-£500 for an exhaust that gained 5 bhp, and another £400 to £500 for an ECU that gained a further 20 bhp, £100-£200 for a filter that gained 4 or 5 bhp, £1000 for a head to gain another 5 or 10 bhp, large throttle body,,, and all plus fitting, and other options would certainly be profitable, but certainly not the best solution to the problem, and very difficult to gain reliable power of the degree required. 

• An increase in engine capacity? The engine would not be suitable for over boring, or stroking to any meaningful degree. Cross that one off.

• A different engine with a large capacity? Problem here - for simplicity the engine should retain the front wheel drive orientation, but the bay is very narrow with two very intrusive unconventional "inner wings" limiting the width available. A rear wheel drive would actually be simpler, although enlarging the transmission tunnel would be costly in terms of interior space, and interior repackaging.

• Supercharger? I am not a fan of supercharging because it robs engine power to generate boost, and from a marketing point of view that's what BMW were doing. Good power is certainly possible, but the parts for low volume of kits are quite expensive, and they are more complicated than Turbos and ultimately far less efficient in terms of robbed power and ultimate power than a turbo (or exhaust driven supercharger). That's why there are far more mass produced cars with Turbos than with superchargers.

• Turbo? A low pressure turbo would leave the engine intact, and fitting would involve only general plumbing work within the ability of the average mechanic. This meets the requirement for easy to install. A large power increase to the 170-200 bhp this car should have as standard for only £3000-£4000 represents value for money that cannot be obtained by any other tuning method - just measure the cost per horsepower of other mods. Turbos have to be chosen well to gain good power at low revs, and this is the only real advantage of a supercharger over the Turbo. The Turbo also meets the requirement for both large power gain and a cost effective solution. Turbo it is then.

We first started working with Turbos for the MINI in the autumn of 2001, and had our first road going Turbocharged MINI in Jan 2002 whilst looking for rather more power than the standard Cooper and One (same engine) offered. This was in those early days before the Cooper S, had arrived. We really wanted the power of the S, but could not wait a year for the car to be launched!

The first car used a turbo that was rather too large for the application, combined with the usual mistake of making the plumbing and exhaust work too big - the result was that we surpassed our target of 200bhp, by some margin (218bhp), but had horrible lag and the conversion was very peaky. In our defence I have to say the choice of parts was driven by budget, by what we had available parts wise, and by what we were familiar with. We were quite disappointed with the road manners of this unit (mark one) - until we drove the Cooper S, which was nowhere near as good as expected!

When we drove the S in the early summer of 2002 we were so pleased to have built an engine on our first conversion attempt that was so much more powerful. (Whilst we had worked on Turbos, and installed other conversions this was our first home grown conversion, because as was the situation at the time, nothing was available and the choice was build it yourself or go without) The standard Cooper S is a very disappointing car, with almost as much lag as our poorly matched and under developed first version, although a well modified Cooper S is a very different beast.

With our second and third attempts we had already learnt the lesson that big is not always beautiful, and concentrated on better matching of parts. We used slightly smaller ducting, and a better designed turbo manifold, and down pipe with the correct turbo for the low boost small capacity engine. The result was a revelation. Although power was down significantly on the first version the car was far more driveable with a far more pleasant power delivery, without the peakiness of the mark one. Power levels were in the order of 160bhp at first, but some experimenting increased this to the levels of the MCT 170 and MCT200 kits. The really good news was that very substantial gains were present low down the rev range and we were happy to trade ultimate power for driveability - we were after all building a car for the road. We have tried not to confuse the issue with a multitude of kits and options. There are two kits and they do what they say on the label. We are happy that the conversions are reliable having run them on our own cars during this time. These low boost conversions are fantastic because you don't need to open the engine at all. They really are a DIY project. The standard engine can easily handle modest boost, and that's just what this kit gives.