It was a 2.0lt Duratec Sports 2000 engine which is pretty much the same as an ST Fiesta but in a race car. The engines are just built properly, mapped properly on MBE on our engine dyno (which is very acurate) and have always given roughly 195 hp. Thinking about it, they are dry sumped as well which also helps a little bit with the power. But as I said, the biggest gains are definately in the exhaust system, most people use a crappy 4-1 manifold on ST's which won't make the power. We have most of our exhausts made by Tony Law Exhausts in Leeds to our exact specification. 4-2-1 with specific lengths and diameters, that's all really.