Well, a larger throttle body allows more flow basically.

When you get all these mods (stage 3, big bore, ported head etc) the only other intermediatary between the outside world and the inside of your engine is the throttle body.

The larger that is, the more that can flow through it.
I've read on here that people get some positive gains from a larger TB.

Oh, and the cams... they come in different shapes offering different 'degrees' of angle.
The shape of the cam determines when the valves open/close and for how long they are open for.
Say for example, on the intake stroke, you want the exhaust valves to close pretty much top dead centre, and the inlet to open at top dead centre.
Obviously, the exhaust must be closed before the intake opens otherwise you'll get blow back through throttle body and I've stood next to car carbs when they've backfired through them.
Trust... I thought I needed a change of underware after that!

So how the cam is ground and shaped changes all of this. There is no 'Ideal' either as it depends on what you're looking for, whether you want top end power or low end grunt.

I honestly couldn't tell you how the shape of the cam affects the power though

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CCC Stainless Rounds, Stage 1 DNA, Stage 2 DNA, PCV With Custom Autotune Map, PCV AutoTune, Home made O2 eliminator, Self machined Fork Spacers, DIY Autotune Switch.