Morning Guys,
I would like to respond to some of the comments in this thread. Firstly I too would have liked more time to discuss the results with you and answer any questions on the day but the fact is we were too busy. I apologise for this and should have inisited on 25 max and would have ideally had another member of staff on hand so I could be more of a host. Lesson learnt and sorry.
That being said I have all the data on the rollers - it datalogs every car as we run it so if there are any questions please pm me with your registration and I will download the data.
With regard to the technique used on the rollers. Pulling away in 4th, 5th or even 6th is not a strain on the clutch as it is only the mass of the driveline and the rollers that are loading the car at this time. The mass of the car itself never moves. The run is started at low rpm to allow boost pressures and the dyno to balance and achieve a smooth controlled run. Inlet temp is measured by the dyno over obd, we do this to achieve consistency. Take a GTI, put it on the rollers at 8:00 and run it. The intercooler and air are nice and cool and a max inlet air reading may be 33degrees. This will give a minimal correction such that the raw engine power and corrected figure are very similar. If we then spend all day mapping it and finally run it at 5:00 we would see iinlet temperatures of 50-60 degrees. Raw engine power may be 10-15 bhp down as a result. Allowing the dyno to correct this figure gives us a similar result to the run at 8:00. The GTI has always had a good intercooler and therefore the runs on Saturday in the cold moist air did not have a great deal of temperature correction at all. Once again any questions regarding the rollers please pm me.
I must say that of all the forum days we have run we have never had so many people turn up early and stay all day despite the weather. All the cars were in fine form and there was little, if anything, worthy of criticism.
Jamie