I am trying to get horsepower out of an engine that can breathe well or have decent compression, but not both.
I was feeling sorry for you for a moment there.
Then I remembered that the one liter BMC's are very difficult to get decent compression
and they do not breathe well . . . . . .
BUT,
none of that stopped persistent dunderheads from setting a new record . . . . . .
Just keep the story of the
Little Red Hen Uhhh, the Harley KR, in mind:
Reduced compression ratio combined with increased flow netted an ~ 20/25% bhp increase. Thank you Mr. Axtell.
3 things are going to be key to your engine, as I see it:
A/ Maximizing effective compression ratio with the precise cam timing required,
2/ Maximizing inlet "ramming effect" with the best inlet tuned length,
d/ Maximizing exhaust pipe tuning over the designed rpm range.
For your engine, I would make sure that all three of these "tuning effects" are set for the same rpm range, ie, the range you intend to utilize. That way, all the benefits of the tuning will "accentuate" each other, raising the power peak higher than any one effect might have by itself.
That's the good news.
The bad news is:
If you need a power band wider or flatter than say, 1500 rpm. If so, then you will have to "spread" the tuning effects, to get the wider power band you may require. This is what was done with MM's BMC "Grenade". It was the only way to get the engine to "pull through" the required rpm range with the gearbox he had.
Needless to say, some math and modeling are required to get things to turn out the way you want. You start by defining some things like top speed, potential gearing and engine rpm range. And just keep pluggin' away at it.
You have already made a good decision by staying away from the rice grinders.
Fordboy