Slow hole shot, but afraid to pull vent plugs...

[jrh5064]

I've got a 2007 Stratos 201xl with a 2007 225 e-tec that I've had for about 6 years now. One of the previous two owners had converted the prop to a merc. I can't remember exactly what the prop is, but it definitely says "Mercury" on it. It's a 3-blade prop, vent plugs reduce the vent diameter in half. I"m not sure what the pitch is, because honestly, I've never been that concerned with top end speed. Jackplate is manual, and I've never messed with it. I'm a firm believer that if it isn't broke, I'm not fixing it. She's been pretty reliable. I rarely top 60 mph and I'm running 5000 or a little over when I do.

However...

When I'm by myself with one livewell full, she shoots right up and I'm gone. With two guys and two full livewells, she's a dog getting up on plane. I bog down 2000-3000 rpm and I swear it can be 100 yards sometimes until she finally gets up on pad. I always start out trimmed completely down and wait until she levels out before trimming up. Some guys in my club have recommended pulling the vent plugs, but I've been running this current set-up for years without blowing a lower unit or my power head. I'm afraid of changing something with the prop and setting myself up for future failure as a couple grand repair is going to really hurt. But, when I draw a co-angler or fish a team tournament, I'd like to get on pad in under 30 seconds.

If any of you have had a similar set-up or experience:

-Does pulling vent plugs significantly increase my rpms at take off?
-Should I pull 1 plug, 2, or all 3?
-At what rpm do I know I've taken too many out?
-Am I taxing my outboard more by bogging down and taking forever to get up on pad, or getting on pad quicker at much higher rpms?
-Wouldn't having uneven vent openings unbalance my prop?

Any advice is appreciated!

[captainrab]

-Does pulling vent plugs significantly increase my rpms at take off? Yes it can. They make several different sizes. Adjust holes till you get your hole shot right.
-Should I pull 1 plug, 2, or all 3? Start with one at a time until desired hole shot is reached.
-At what rpm do I know I've taken too many out? When the prop blows out
-Am I taxing my outboard more by bogging down and taking forever to get up on pad, or getting on pad quicker at much higher rpms? Yes, you are bogging the engine On jacked up hole shots. High rpm not so much.
-Wouldn't having uneven vent openings unbalance my prop? No

Notice the rpms during holeshot when you are by yourself and document that rpm. Adjust plugs until that rpm is achieved under load then double check wen alone again. A 4 blade handles a load much better than a 3 blade and that may be an option since your seeing such a drastic difference when loaded or the prop may be too large in the base case.

Heres the basics. Vent holes are just that. Vents. They allow gas to enter on the prop blades which inturn allows the prop to slip a little thus increasing rpm and power. Once the boat is on step the water pressure surrounding the holes is greater then it preventS gas from escaping onto the blade which eliminates slip.

[XingEyeballs]

1) Ususally to an extent
2) small changes are best, one at a time
3) you want to see the motor hitting 3500-4000RPM’s as it breaks over on takeoff
4) yes, you’re actually stressing the motor more continuing to let it bog down on takeoff
5) they don’t need to be even
prop pitch, type, blades would be very helpful because it really sounds like too big of prop. Struggling out of the hole and that boat only hitting 60 WOT with 5000 is low. If there’s too much venting you’re going to hear it, the prop will blow out a little and rpms will jump 4-5k. Check the prop information and report back

[PMantle]

No doubt I would either pull one or do some drilling of them. You're not going to harm your engine.

[John Jackson]

Pull one and test. I should help. It if helps but not enough, pull a 2nd one. If needed, pull all 3.
You can do it easily, just knocking the plug through with a hammer and socket that just fits through the hole.

[jrh5064]

Thanks to all. Hope to get out this weekend and mess around with it.