Not sure if this link has been posted before but I thought I'd post anyway even though David isn't taking on any engine worlk at the moment.
There is some really good info to be had here regarding general and specific tuning of mainly Ford engines.

http://www.pumaracing.co.uk/

ive just read his account of how not to set a car up on a rolling road and Customers.
They both make very entertaining reading.

Very knowledgeable chap and extremely good engineer, is Dave Baker.

He may be a nice chap and I am sure he can build a good engine but it has been demonstrated by cleverer people than me that it is incorrect to rely on wheel BHP.

A quick example.
Rolling losses on the are speed related.
More so on a rolling road because the tyre is sqaushed in two places.
Measure power in 4th gear then change to 3rd gear and measure again, the wheel speed and therefore the loses are reduced - bingo you have more power - at the wheels
Change the tyre size/type/pressure and you can create another figure again - at the wheels - again meaningless.
The rundown test while not perfect does give a pretty reliable and repeatable indication of those losses.

Lets not forget also in his example he uses a tuner who sounds like he can barely use a spanner let alone a rolling road.