Just giving this thread an update. I gained 7-8 mph on GPS. Boat runs a solid 74 mph loaded and 7mph with a light load. I'm extremely happy with the results. Power gains were very impressive.
BTW that is with a stock 26 pitch bravo prop. I'm sure if I got it labbed I'd see 2-3 more mph.

you would have picked up more mph than that with two hand rubbed coats of speedwax, dont throw your arm out of joint patting yourself on the back just yet..

That is awesome ! Checkmate builds a pretty efficient hull.

Cool story bro.

Wax helps with hole shot, 400 grit on the wetted surface helps with top end.
Laminar flow, turbulence, fluid dynamics, hydrodynamics. Just sayin'.

Yeah sure there Phil, if this guy picked up 7-8 mph with a ecu upgrade and a liitle grinding I'm pretty impressed, wouldn't hold my breath for speed wax to do that though!!! Brian, thats a cool deal, Merc must have left alot on the table with the 380 motors, your doing good, Smitty

This has been a hot topic, I have a Caliber 1 custom 28 Thunder Mid Cabin Open Bow.
I have the 502 HO MAG 430 HP.
Still has the cats in it.

I would like to see some numbers after someone has done the cat delete, and tune.

Versus headers and tuning.

Thanks group!

Rip Van Winkle.....