I have a fresh 454 magnum carb motor. I'm looking at the universal whipple EFI setup which is about $10k. Pricey, but should fit under the hatch, look great, and hopefully be reliable.

-First off, how do I go about tuning the thing with the CPU they offer?

-When my 454 goes, and I upgrade to a 502 or 540- will I have to change injectors and other parts? I don't mind re-tuning for the cubic inches, but I don't want to "waste" money setting up for a 454, then buying new stuff for a bigger engine.

The other option is the procharger setup with a blow through carb, but I just don't like the looks of it- I like the integrated factory look of the whipple.

My guess is that a Whippled 454Mag is going to make 550HP and the same setup will work to make 600HP on a 502Mag.
On a 540cube you will likely need larger injectors...

Adding 150HP to your 22' Donzi is going to be one wild ride. I hope you adding twin ram full hydraulic steering...

Yes, twin ram full hydraulic steering is on order right now. Should be installed next month. The HP upgrade is for the future. Just looking for the best route to go. Since the engine is fresh, I'm still leaning towards the whipple- a 502 in the future would be fine- no need for anything over 600HP in a light 22 footer...