But I am idly (pun!) curious. I am going to ask John Eales. He should know better than most because he uses an inhouse flywheel dyno and his racing customers often use rolling wheel dynos as well. Let's see if I get an answer. He always has been very kind and we have pals in common. gmg
QUOTE JOHN EALES:
> Lorne
>
> We are all well thanks and I hope you are the same.
>
> I use an engine dyno so the numbers are flywheel torque and HP.
> Rolling roads generally have a rolldown feature that measures the transmission (etc) losses.
> As a general rule a 2 wheel drive g/box and axle take 20/25%
> This also depends on which gear is used as indirect gears take more power than a direct top gear.
> I hope that this helps.
>
> John Eales
> J.E.Developments
> Claybrooke Mill
> Claybrooke Magna
> LE17 5DB
> 01455 202909 As has been repeated many times, at the core of this discussion is public's common miscomprehension of dynos,
fostered by Media writers who don't understand what they are writing about and/or want to pander to their audience. 
They were not invented for bragging rights or comparisons from one car to another.
Dyno figures, regardless of where you take them or who they come from, are only of vital interest when tuning a specific vehicle to suit, preferably, a specific owner. Dyno operators couldn't care less beyond that. John was kind.
gmg
P.S. Do any of you remember the sad lawsuit the MMC was faced with when an Austrian Plus 4 Supersports buyer (the original 4 wheel Supersports and not the many model lines named after it) found his dyno was lower than the Factory's measurement? I have often hoped, fervently, that he sold that car on back when. Divine justice.
