"Backfire" Jim---The later model is no easier to supercharge, but one
can make more boost (power) with the lower CR head, before troubles can
begin. More boost means you can properly add more fuel with this
"extra" air. We know it's easier to push air and fuel into an engine
than to try just sucking it in, given the time frame. But you probably
already knew this. More to your questions..
As with normally aspirated engines, a performance cam works similarly
with one that has forced induction. More power will be seen at the upper
rpm band. A supercharged engine will get some of this "lost power" at
the low end back, but it will still be a trade off. An engine with a
performance cam can generally run with more boost pressure than one with
a stock cam, due to some pressure bleed-off. (That's sure to bring a
howl from a few looking in!)
Good exhaust porting should help any engine's power. Again, there might
be some trade off here at the low end, but others can shed more light
here than I.
I cannot tell you which cam to install with a boosted engine. A rule of
thumb would be, if you do mostly stop-and-go city driving, stay with the
stock, or nearly stock grind. If most of your driving is on the highway,
you may want one that comes on later, as the longer duration also helps
out on the pumping loss you were concerned with. The boost is usually
set up to come in "on demand". (Absence of vacuum)
Dick
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