5.8 penta, options for adding power

[Burns363R]

Are there any modifications that can be done to add power to our 5.8 motors? Advance timing? Through hull exhaust? Maybe something like Quick quiet's. I know raising head flow and compression arent really options.

Also is there a reason they only spin our drives to 4400 vs 4800 like other engines?

 

[Bondo]

Ayuh,..... What induction ya got on yer motor,..??

2 bbl. carb,..??
4 bbl. carb,..??
Efi,..??
Mpi,..??

Neither advanced timin', nor thru-hulls will help, at all,....

Advanced timin' is more apt to destroy yer motor with detonation, 'n melt down,....

 

[Burns363R]

Its a FL motor, Holly 4 barrel.

Only reason i asked about advancing timing, was my experiance with several later model 5.8's i had in my trucks. I was able to take them from Ford's 10degrees base timing to 18 degrees and pickup some very serious gains with no detonation. I assumed it would be fine in a boat using premium fuel. It was a large gain in the truck, enough so that i did it after going from 31's to 33's on the truck, and then advanced the timing and the truck was quicker and ran better on the 33's due to the additional timing.

Anyways that was my thought process. And as far as through hull exhaust, the exhaust system seems so restrictive, i would think that a quick dump would allow the engine to breath better at WOT, even if it is only 4400 or what ever RPM.

Why does the Volvo only run them at 4400 and everyone else runs them at 4800?

 

[Bondo]

Anyways that was my thought process. And as far as through hull exhaust, the exhaust system seems so restrictive, i would think that a quick dump would allow the engine to breath better at WOT, even if it is only 4400 or what ever RPM.

Why does the Volvo only run them at 4400 and everyone else runs them at 4800?

Ayuh,.... The "Restriction" in marine exhaust is in the common manifold, there's no runners inside,....
Ya need Headers, then thru-hulls to make any sorta "Difference",....

Donno why they say 4400,.... I figured is was a 2bbl. carb,....

Prop it down, 'n wind it tighter if that suits yer fancy,...