just a thought, all the cars that claim to have run accurately, were new cars??
Would having lower tread on the front wheels cause differences in RR readings??
If all models of cars were strapped down the same, yet the newer cars ran nearer to their Pre claimed bhp..
Anyone with a a mk5 GTi running new tyres and what bhp did you get yesterday? Maybe tyres not gripping aswell.
I know Jim commented on my vreddestein tyres not getting enough heat in them causing issues on my 1st few runs before.