I need more speed

[Buster_boy]

I have a 16ft Sylvan pontoon with a 2006 Mercury 9.9 Bigfoot ELB with a standard four blade prop. I'm on restricted waters 10hp 10mph max. Today I was passed by a bigger pontoon 21-22FT with a 9.9 Honda. He went by me pretty easily, not like I was standing still but still.

What am I doing wrong? What mods can I make to keep up? I about the bigger carb to make it 15hp but what else?

 

[jimmbo]

Get rid of all unnecessary weight. Kids, wife, mother-in-law are to be left ashore. Mistresses and Girlfriends are allowed on board. As for the motor... Is it mounted at the correct height? Is the trim set properly? What rpm are you turning at WOT? Is it at or near the upper end of the recommended range? You said you have a 9.9 Bigfoot, perhaps the regular model would have provided a better top end, but poorer maneuverability around the dock.

 

[GA_Boater]

Is the main motor tilted out of the water?

How much more speed do you need on a 10 MPH lake?

 

[Buster_boy]

Jimmbo - I do not know. I'm as green as my lawn as I'm a newbie at boating. Here's a pic. Maybe you can make some suggestions?

GA - As fast as the bigger boat that passed me.

 

[GA_Boater]

GA - As fast as the bigger boat that passed me.

So the Water Cop can give you the ticket?

How fast are you going at WOT? Tilt the main motor out of the water and raise the kicker, it's buried.

 

[Buster_boy]

Yes the main is at full tilt - it has to be on this water. I wondered about the kicker. That mount is the same height as the main transome, but I didn't realize the stern would sit so low when I built the mount.

 

[HotTommy]

If 16' and 21' pontoon boats race with the same motors and the same total weight, the 21' boat should be faster. Because it has larger (longer) toons, it will sit higher in the water and have less drag. As your boat is not level, it will have more drag because the back ends of the pontoons are sitting even lower in the water. I mention this because I doubt that your speed problem has anything to do with your engine other than, perhaps, how deeply it sits in the water. Anything you can do to better balance your load and level your boat should help some.

 

[jimmbo]

If 16' and 21' pontoon boats race with the same motors and the same total weight, the 21' boat should be faster. Because it has larger (longer) toons.

Like displacement hulls behave

 

[jimmbo]

Buster.... You could build a jack plate to mount the kicker higher. Looking at the pic you can raise it at least 12 inches, maybe 15, and the prop will still be under water. From your initial post I thought the 9.9 was the main engine

 

[Buster_boy]

Jimmbo - Yes, the 9.9 is the main. I thought you were referring to the Johnson since it's in the center. I have an additional mount that raises and lowers. I wasn't sure if I was going to need it since I built the mount the same height as the transom. I had no idea the boat would sit so low in the back. Also, I'll need a different connecting rod for tandem steering and that guy costs $300.