Pavlo

That graph looks rather odd, 130hp losses on a dastek dyno in 4th gear isn't what I would expect, it looks rather like the coast down losses might be somewhat overstated, which can happed if you don't get the settings correct with a dastek dyno.

Shaun

Paul,
Based on your Dastek dyno wheel figures, these other flywheel figures are circa 60bhp overstated then? Whoops.

Pavlo

You cannot state that as fact, it woud be unfair.

However in my experience I would expect a car running to around 130mph on the dastek dyno to have losses in the order of about 80-90hp (any other dyno is not included in this discussion, they are all different). What you need to look at is the actual graphs on the power run screen which show the actual recorded coastdown losses, and the line that is curve-fitted through it to avoid the big "bump" at the end. If the curve fit is taken to close to the end of the coast down losses curve, it will create a losses curve that suddenly dips at the end of the run, adding non existant HP to the wheel figure.

It's down to the dyno operator to ensure that this element of the graph production is carried out correctly. The good news is that all the original info is stored, and graphs where the flywheel HP is a little skewed can be easily corrected.

But as I initially said, it could just be one of those oddities and everything is bang on.

Paul