A year ago I started racing my Ralliart Colt at a local hillclimb in the Barossa valley (www.collingrovehillclimb.com.au).  At the time my car was still running the stock exhaust and as a result delivered its power in a rather torquey, all or nothing kind of powerband low in the rev range.  It was very hard to control wheelspin on this narrow winding tarmac and it was very frustrating seeing my car perform well in the first two sections of the hillclimb, only to be a second slower in the last third of the course relative to other competitors.  It felt like the car had the heaviest flywheel ever, so heavy, that it was impossible to control wheelspin once boost set in.  No amount of throttle control seemed to help – it was either [...]