I can't find a straight answer anywhere. Some sources say these engines are EFI, some say they are not. Some say they are Vortec heads...some say not. I guess having them hooked to bravo's throws it off.

What I do know.
5.7LX with bravo III drives

Serial numbers:
0k027498
0k027506

You should have a 1997 - 4 bbl carb rated at 250 hp propshaft. This engine has T - bolt V ignition, roller cam and what Merc called at that time Gen + cylinder heads (vortec persay). Also should have hand removable blue water drain plugs, one serpentine belt (new for 97) and RPM range was 4400 - 4800,

Also in 1997 was offered 5.7L with 2 bbl carb only rated at 210 hp propshaft. RPM range of 4200- 4600.

Volvo had the same and was rated at 215 hp at the prop. and their 4 bbl was rated at 260 hp at the prop. FYI

Thank you very much! A mix of what I suspected. Glad to see the Vortec heads!

Its not uncommon to see bigger and or heavier boats with smallblocks using Bravo III's - basically somewhat under powered. It is very common with Sea Rays 26 ft and down, Cobalts, Chaparral, Crownlines, Regals amd so on from the REC side of boats