Radiators: Is 22" enough for 400 HP?

I bought the AE375 radiator from Ledfoot racing. I was able to just go there an pick it up to save myself some money. It came out to 200 bucks.

In order to prep for replacing the radiator, I figured I should flush it first.

So after running some Prestone Flush and Cleaner I drained the radiator.

What came out literally looked like poop. It was nasty. Then I refilled the radiator with distilled water and did it again for another day to loosen up any remaining crap. After driving that around for a few miles for a couple of days, I drained it again. What came out was less poopy looking, but still pretty gross. This was over the course of this weekend.

Today, I pulled out the old radiator and flushed it out with the garden hose, bolted it back up and added more distilled water and about a gallon of concentrated anti-freeze. I'll leave that in until next weekend because I ran out of daylight.

I'll attach some pictures.