I have just installed Wolfi's excellent SB2C Helldiver and aliased it to Lawdog's F8F Bearcat Sound.
I have AlphaSim's Bearcat with its sound also aliased to Lawdog's F8F Bearcat Sound.
The Helldiver's engine sounds like it is stuck in idle; it barely changes as the throttle is varied.
The Bearcat's engine responds perfectly to throttle changes.
I was baffled by this until a Readme! Readme! in Nigel's Centaurus sound pack provided a clue: Nigel asks that certain changes be made in the [piston engine] section of the aircraft CFG. I plugged the Bearcat's values into the Helldiver and voilá.
The implication is that sound packs are tailored to aircraft--or is it the other way? Is there a guide to HOW this should be done?