Horsepower upgrades for 315 hp Merc.

Are there any upgrades you can do to bump the horsepower up a little? K&N filter etc.??

Not really without spending some $$$. The difference of a K&N on a boat probably wouldn't be noticeable. I actually e-mailed indmar one time (I know it wasn't Mercruiser) to ask them about some upgrades to a 325hp model they had, they told me there was nothing that could really be done that would really be feasible. Most any option is cost prohibative.

Boats don't have an actual air filter, so a K&N might actually be more restriction.

If you're just looking to plane out faster with ballast, get a lower pitch prop. You would have to spend big money on the motor to get the same holeshot improvement.

The 11 yr old 320 hp motor in my VLX with just an Acme 537 prop and has NO PROBLEM with almost 3k of ballast. It's night & day compared to the stock 14x18 prop.

Forgot Trace, it's a flame arrestor huh. No element. Yeah I guess after having driven a Bu v-ride with a 340 hp motor the wheels just started turnin. I'll probably end up repropping. Thanks for the comments!
John