mdonohue,
Well you might indeed be right, as I noted above I've never built a stovebolt, but I am wary of "advertised" durations of cams in general because they are all over the map - the advertised duration is measured on the shallow part of the ramp so its hard to tell how the engine will make power or even idle from that number alone.
So I tend to go by duration at .050" lobe, where the ramp is steep and it is a more consistent way to gage how a cam will run.
That said, it is true that the IDLE quality depends on the ramps. Long shallow ramps are easy on the valve train but will idle rougher. The Bulldog has a fair bit of duration at .050 (211-220), but given its low advertised duration 254-264, it could have fairly steep ramps so might have a smoother idle - this is kind of what roller cams do.
I hope it helps to exchange info in the thread, it is helping me for sure, to dig into this engine family a little more!
