Better performance by raising the outboard one or two holes?

I am working on buying an '07 Tidewater 21' BayMax powered by a very low-hour 140 HP Suzuki. I saw the boat last Fri. and liked it, so we took it out yesterday for a sea-trial.

While running it, I noticed it put up allot of spray beside the O/B's mid-section until the motor was trimmed up. Even then it was nearly impossible to see the anti-ventilation plate...I estimate it was nearly an inch below the water when on plane. Additionally, it topped out at just 30 knots with 3 people, ~1/3 tank of gas (15-20 gallons) and only the basic safety supplies.

During the sea trial, the boat was at a slip and not on the trailer so I couldn't place a straight edge along the keel, but it has two holes beneath the current mounting bolts.

Do you think the excessive spray and low top speed will be improved by raising it (meaning the o/b mounting bracket) a hole or two?

Re: Better performance by raising the outboard one or two holes?

Interesting, ours it the opposite way. It get's best performance when raised much, but also allot of spray besides the mid-section. Part of it might be that our powerhead is not as tight anymore as it was when built some 40 years ago.

Ahoy!

Re: Better performance by raising the outboard one or two holes?

Boats will kick up spray when the antiventilation plate is too deep or significantly above the surface of the water. I think you will get less spray, and likely better performance if you raise up the motor. This is a trial and error exercize, so take some statistics on RPM and top speed, before you raise it, and on every adjustment.

Re: Better performance by raising the outboard one or two holes?

Thanks...I hope to pick the boat up tomorrow and will take good notes on speeds at various RPM before moving forward. I'm also considering installing a manual jack plate, so this would be the time to do it.

Re: Better performance by raising the outboard one or two holes?

Here are a few pictures from the owner before I did the sea-trial.

The motor looks pretty low to me just from these pictures.