The Green line on the graph was from a rolling road session almost a year after fitting the Blydenstein head. In that period I'd refitted the  induction system, sorted the larger throttle plate and changed the cam belt, knackering the Vernier pulley in the process. I'd also had a 2" Stainless exhaust system fitted. I'd not expect any of these changes to make a massive difference to power.

Torque is up at 144 lb-ft and power is down a bit to 145BHP. Allowing for rolling road discrepancies then in general the figures are about what I'd expected.

 In more detail it does appear that a bit of top end power is missing and the peak torque is suspiciously high. I would tend to point the finger of blame at the rolling road data - the mph to rpm figure was manually entered by the operator. Getting the numbers wrong would increase the torque and shift the curve to the left slightly. All the same, I would hope that optimising the cam timing might gain a few BHP at the top end.. There is also  a  "flat spot" at 3,500rpm. This is noticeable on the road: the car takes off at 4,000rpm. The engine was running a bit rich at this point. It all makes a custom mapped chip look more desirable. Just money holds me back.