Plug gap

TT5.9mag said
Any time I see an ignition test, and that includes ANY spark plug gap test, where they only reference peak HP I know it’s bullshit. WHY?

Because the load on the ignition system, and the plug, is highest when cylinder pressure is highest. And that happens at peak volumetric efficiency, which is (and always will be) at peak torque.

Actually idle is one of the hardest on the ignition system. The high residuals due to high vacuum make the kv demand a challenge. Modern engines with cam phasing (especially DOHC engines) help quite a bit. DOHC engines can really reduce overlap/residuals quite a bit.