Subject: Re: Tappet clearances - why the variation?
Newish modern cams, all new rockers. I suspect the notoriously inefficient induction tracts of the 2 Litre are the dominant problem, your downdraught head is a very good move I'm sure.
I know remarkably little about dynos but I can see that the calculations that purport to correct power at the wheels to power at the flywheel can be dodgy. As you say, they are certainly excellent comparison tools. Taking off the pancake air cleaner on my single SU produced an extra 2 bhp at the peak of the curve.