Cruising speed on 32 Sundancer with 6.2 engines

[Bob 32]

I recently purchased a 2005 Sundancer 32. For me to get the bow down I have to have the trim tabs all the way down and run at about 3700 RPM and that is about 23 MPH. Not sure if this is too high of an RPM or not? Seems like anything slower the boat labors as I feel it is very heavy in the back

 

[Craig]

3800 to 4000 depending on load and conditions is the sweet spot. No tabs needed except for leveling side to side.
That should get you 26~28mph.

 

[Bob 32]

3800 to 4000 depending on load and conditions is the sweet spot. No tabs needed except for leveling side to side.
That should get you 26~28mph.

Thank you Craig

 

[Golfman25]

That engine has a high rpm power curve. WOT is in the 5000-5400 rpm range. So you'll need those extra RPMs to create the power needed.

 

[Bob 32]

Great thanks for the info

 

[Motoguy2158]

I have the 34 Sundancer and with the same engines. They love to run up around 3800 to 4000 rpm. They were built for that. However, SeaRay undersized the trim tabs on these boats per Bennett. If you look any your boat size on their site you will see it's one or two sizes too small, partly due to prop pockets. I up the size of mine from 12 x 18 to 12 x 24 and put on drop fins as they make the trim tabs work like a size bigger. I can cruise at 3200 to 3400 now with tabs partially down and no bow raise. It a different boat. A guy a Bennet told me they undersize them for coat and to keep the boat from broaching if you came down the back of a wave it ocean type seas. The other upgrade i did last year was to install a set Acme 4 blade props on the boat. It jumps out of the water and cruises about 2 gph less than with the OEM three blades. It feels like I installed bigger engines. Completely different boat.

 

[Bob 32]

I have the 34 Sundancer and with the same engines. They love to run up around 3800 to 4000 rpm. They were built for that. However, SeaRay undersized the trim tabs on these boats per Bennett. If you look any your boat size on their site you will see it's one or two sizes too small, partly due to prop pockets. I up the size of mine from 12 x 18 to 12 x 24 and put on drop fins as they make the trim tabs work like a size bigger. I can cruise at 3200 to 3400 now with tabs partially down and no bow raise. It a different boat. A guy a Bennet told me they undersize them for coat and to keep the boat from broaching if you came down the back of a wave it ocean type seas. The other upgrade i did last year was to install a set Acme 4 blade props on the boat. It jumps out of the water and cruises about 2 gph less than with the OEM three blades. It feels like I installed bigger engines. Completely different boat.

This is great information. i will reach out to Bennett to see what they recommend for a 32 foot. Did you have to change the cylinders as well as the trim tabs? Also how did you go about sizing the props for the boat? Would you just reach out to Acme to see what they recommend?

 

[Motoguy2158]

No cylinder change required, they work just fine... They push the bow down with very little effort.
RE: Props: I called Acme Marine and spoke with their technical sales. They ran the numbers for the boat and gave me a recommendation. They perform exactly as they stated hitting the WOT on the spot and improved cruise performance. They were super helpful and worked me up a deal on the pair.

 

[Bob 32]

No cylinder change required, they work just fine... They push the bow down with very little effort.
RE: Props: I called Acme Marine and spoke with their technical sales. They ran the numbers for the boat and gave me a recommendation. They perform exactly as they stated hitting the WOT on the spot and improved cruise performance. They were super helpful and worked me up a deal on the pair.

Great, this will be my winter project

 

[Motoguy2158]

Great, this will be my winter project

Bob, My original props we're (3) blade fly Torq props (OEM) on boat that were a 17" x 19" with medium cup.
The Acme props are (4) blade, 17" x 17" with medium cup. No prop noise in prop pocket, no vibration and smooth
pull right up too wide open. Gettin on plane is a 1/4 push to throttle and it jumps on plane with tabs partially down.
Best money I spent on boat by far.

 

[Motoguy2158]

Great, this will be my winter project

I send you my drawing fo the tab extension i had made. They simply bolt on.

 

[Motoguy2158]

Heres a screen shot of drop fin and extensions

 

[Bob 32]

Heres a screen shot of drop fin and extensions

Did you just bend these up and drill holes in the existing tabs and bolt them on? Do the bends face down as the existing tabs the bend faces up

 

[Motoguy2158]

In my drawing you're looking at top view. Bend up and drill and bolt. I used the drop fins to bolt along edges and then the angle bracket where the cylinder hooks i bolted it also. I use a flat sound head stainless screw with nyloc nuts