Exactly how do "bigger" injectors increase horsepower?

I PM'd Don M a few days ago but didn't get a response.

 

The holes on the tip of the injector are larger. A lot of aftermarket injectors have more holes as well. This increases the amount of fuel entering the combustion chamber, increasing power up to a point.

The injectors aren't acutally "bigger" just the holes at the tip. Which you can't even tell by comparing a stock injector with an aftermarket injector (unless the number of holes is different).

Technically the injectors are smaller, as in less material.

 

Aftermarket injectors often have custom tips (like Don M's do) which are thicker and stronger, so they actually have MORE material, even with more/bigger holes.