>>>*There are a lot of factors to consider when choosing a camshaft.
Often the hard part to understand is that one can make an infinite number of profiles, all with exactly the same lift/duration, and all of them completely different.
*Lobe timing is the key, and how fast the valve opens once it starts to move.
Now some report "lope" even with our design. In nearly every case, I would guess that the head/block have been surfaced. This retards the camshaft timing, and yes, our design will lope and tend to operate in the higher RPM ranges more efficiently if it is retarded by even 2?.
The most common "272/431" design was made by Crane initially, that design is now copied by just about everyone.
We found the .050" lobe timing of 220? to be just a tad too much for the EFI engines, so we reduced it to 219?, (270/430) mostly to improve emissions, and idle quality. We also use the factory 110? lobe centers.
The Crane design is ground on a 108? lobe seperation, and yep! It will lope.
"Lope" begins when airflow velocity is slowed as the area of volume created by the valve action and port exceeds the volume the engine can draw.
This can be improved some by advancing the camshaft by around 2?. There are other tricks, but all of them are much more expensive...*EB