MadBill wrote:You're shifting the goalposts there Randy. Neither the engine in my example nor I'm sure in DV's remarks, were targeted at a 4,500 RPM power band. In fact for the former, with a very high stall converter, it was more like 6,500 to 8,500 and was to be launched at well over peak torque. Indexing effects below say 6,000 were totally irrelevant.
My hat's off to guys that can wring out top end power within the straightjacket of EMC rules, but such engine are not optimal for many forms of racing.
Not moving the goal post at all. You posted a cam being un-responsive is a sign the cam is wrong, on this thread, in which the engine is being pulled from 3000-7000 and on up to 7500 some. I posted my reasons for disagreeing.
By the way SN isn't an EMC engine. It's headed for a street car if it survives all the dyno time. LOL
As far as the results from your cam test, (if that's what your asking) would suggest to me IVC is the reason. IVC seems to run the show a lot.
The one other thing could be overlap position VS piston position. I've seen some evidence to suggest when it's too much overlap or not enough the position of it is a little more picky.