It matters, but it’s not some magic squirrel ****. The converter or flywheel on the back of the crank is the biggest RPM retarder on the engine.
RPM and the ability to gain RPM (which is the definition of acceleration) is far more limited by the inability of the heads to feed the engine.
Standing there, blipping the throttle and thinking the engine is really zippy doesn’t mean a thing. What the engine does under load is what counts.
You can’t test for that on a water brake dyno either.
