Adding 22 cubes,,, power increase? 528 to 550

thanks in advance! Ignition is a new MSDdigital 7. Plugs at .025 but i can try .022 after a few passes. I wanted to dyno this deal but the piston coatings dictate a very long three time full warmup cycles with total cool down between each cycle. Timing will start at 33 since it ran best at 34 before.

You guys mind explaining that piston coating ? ------Never hears of it !!