290 Sundancer Prop Question

[Chasing Limes]

Every boat is different, so don't take this is a golden rule, but on our 98 290 I run twin 5.7EFI 260HP Alphas with 4 blade Mercury Diamond4 14x20 Aluminum props. I turn 4600 RPM at WOT around 37mph and cruise around 3100 @ 27mph

If stainless I would have needed to step pitch down a bit, since the aluminum flexes. I ended up testing 3 different sets of props to get to our final selection...so it takes some time.

Strecker,

We have a '98 290 DA with twin 5.7 TBI 260 HP Alpha 1 Gen 2. Existing wheels are (were) 14x19 stainless. We re-powered it when we bought it but it has been a pig to get out of the hole. I don't trust the tachs based on what they read vs. the timing light when we did the engines so I didn't do any math on WOT, Cruise or idle speeds. We had a log wedge itself between the lower unit and the prop in Kent Narrows last year and it turns out we tweaked the starboard wheel.

Now have a set of Michigan Wheel 14x18 Stainless sitting on the bench waiting for the weather to break.

Did your rig have the 14x19 on it before you made the switch? We have done major choreography for the last two seasons... My wife and my oldest daughter know "the look" to run forward to the v-berth if we have guests on the boat.

 

[Todd M Caldwell]

Strecker,

We have a '98 290 DA with twin 5.7 TBI 260 HP Alpha 1 Gen 2. Existing wheels are (were) 14x19 stainless. We re-powered it when we bought it but it has been a pig to get out of the hole. I don't trust the tachs based on what they read vs. the timing light when we did the engines so I didn't do any math on WOT, Cruise or idle speeds. We had a log wedge itself between the lower unit and the prop in Kent Narrows last year and it turns out we tweaked the starboard wheel.

Now have a set of Michigan Wheel 14x18 Stainless sitting on the bench waiting for the weather to break.

Did your rig have the 14x19 on it before you made the switch? We have done major choreography for the last two seasons... My wife and my oldest daughter know "the look" to run forward to the v-berth if we have guests on the boat.

We bought our boat last Oct and it has the 19” props on it and like your boat it is a pig to get on plane. The parts manual for our boats says it came with 14.5x17” I am trying to find someone local that has a pair I can test out.

Todd

 

[Chasing Limes]

We bought our boat last Oct and it has the 19” props on it and like your boat it is a pig to get on plane. The parts manual for our boats says it came with 14.5x17” I am trying to find someone local that has a pair I can test out.

Todd

Todd,

We are replacing gimbal bearings, bellows and some other bits prior to splashing in. Once we are wet, I will post the details. The guy that did our engines chatted with an old salt after we did the engines and his response was "4 blade, drop an inch in pitch, you'll love the boat"

 

[Todd M Caldwell]

Todd,

We are replacing gimbal bearings, bellows and some other bits prior to splashing in. Once we are wet, I will post the details. The guy that did our engines chatted with an old salt after we did the engines and his response was "4 blade, drop an inch in pitch, you'll love the boat"

Please let me know... I have 5.0’s and I think I read you have 5.7s. So you’ll have more Hp and Tq. I had a 24’ Maxum and it had a 4 blade prop. Got on plane really good but WOT was 30 mph at 4700rpm with a 5.7

 

[Strecker25]

Hi guys, I did have the 14x19 vengeance 3 blade SS props prior. They ran fine, but I couldn't stay comfortably on plane under 24-25mph and cruise was over 30 close to 3600-3800 rpm. Way to high for the kind of boating we do, I wanted a slower minimum planing speed and more efficient cruise. With the 4's we get 1.2-1.4 mpg at best cruise now.

Never had much of a problem getting on plane, probably 5-7 seconds by slowly throttling up. It's a heavy boat, especially with full fuel and water, so I didn't expect it to plane quickly but the 4 blades helped that a bit too

 

[Chasing Limes]

Todd,

'Limes splashed in last week and our engine whisperer almost went swimming on the first pull. With 1/2 tank of fuel (and no beer) on board, we planed in 6 seconds from idle with no trim tabs. (this was a 30-45 second process before) We loaded her with fuel and 2 families this weekend for a 40 mile cruise, and saw 10-12 seconds to plane, can stay on plane at 3,000 rpm @ 20 knots. Nice 27 knot cruise at 3,250, and we can flirt with 38 knots at 4,600 rpm.

The stern rides higher in the water now. We did the updated exhaust bellows so when we pick the drives up a bit you can hear 2 V8's ever-so-slightly, and the boat just seems to not be laboring so hard to stay on top.

I put the props in my cart at 4 different places back in November. They started at $700 and got delivered to my door for $424 including shipping in Feb. It costs one fill up of fuel to turn these boats from pig to stallion. Wish I had done this 2 years ago.

Cheers

 

[Strecker25]

Todd,

'Limes splashed in last week and our engine whisperer almost went swimming on the first pull. With 1/2 tank of fuel (and no beer) on board, we planed in 6 seconds from idle with no trim tabs. (this was a 30-45 second process before) We loaded her with fuel and 2 families this weekend for a 40 mile cruise, and saw 10-12 seconds to plane, can stay on plane at 3,000 rpm @ 20 knots. Nice 27 knot cruise at 3,250, and we can flirt with 38 knots at 4,600 rpm.

The stern rides higher in the water now. We did the updated exhaust bellows so when we pick the drives up a bit you can hear 2 V8's ever-so-slightly, and the boat just seems to not be laboring so hard to stay on top.

I put the props in my cart at 4 different places back in November. They started at $700 and got delivered to my door for $424 including shipping in Feb. It costs one fill up of fuel to turn these boats from pig to stallion. Wish I had done this 2 years ago.

Cheers

So yours are the Michigan 14x18’s? What’s your WOT rpm?

Amazing what the correct prop can do. Like you, ours was night and day.

 

[Handsome Transom]

So might as well jump in here I have a 268Da 7.4 liter engine and bravo drive with a cavitation wing spinning a 3 blade stainless mirage prop #48 18278 A41 17P. WOT 4800 no dink on my platform any would not add one for this little boat. I start to drop off plane below 3600 3700 .
Can a guru help me get to keep on plane down to 2800 rpm with a prop recommendation. I'm ok with being over propped slightly and dragging WOT DOWN TO 4500

 

[Lazy Daze]

So might as well jump in here I have a 268Da 7.4 liter engine and bravo drive with a cavitation wing spinning a 3 blade stainless mirage prop #48 18278 A41 17P. WOT 4800 no dink on my platform any would not add one for this little boat. I start to drop off plane below 3600 3700 .
Can a guru help me get to keep on plane down to 2800 rpm with a prop recommendation. I'm ok with being over propped slightly and dragging WOT DOWN TO 4500

Bravo 1?

How much do you use your tabs? They make a huge difference. Adding span to the tabs can have a marked increase, as well - more-so than chord. Some have reported differences by adding drop fins, too. I don't have personal experience with the drop fins, though. But, when it comes to a prop, it sounds like a 4-blade is more your style.

 

[Handsome Transom]

Bravo 1?

How much do you use your tabs? They make a huge difference. Adding span to the tabs can have a marked increase, as well - more-so than chord. Some have reported differences by adding drop fins, too. I don't have personal experience with the drop fins, though. But, when it comes to a prop, it sounds like a 4-blade is more your style.

Yes it is a brave 1 my model year went to that more robust drive . Previous years 7.4 alpha drives had too many service /failure issues due to the hp of the 7.4. I use tabs and trim when on plane but tabs only to compensate for conditions due to my thoughts that they add drag and defeat the purpose of trying to save fuel? Getting on plane isn't an issue just keeping there at a more modest rpm. Any suggestions on manufacturer or stainless vs aluminum . Also what about pitch. I'm aware good prop shops can answer some of these questions but nothing beats direct experience with s particular boat
Thanks

 

[Lazy Daze]

I was actually just trying to confirm whether it was a Bravo one, two or three. It makes a difference to know which setup.

No! DEFINITLEY use your tabs more! They have less impact on loss of speed than trimming the drive does. In fact, proper use of the trim will HELP with efficiency. Tabs are a great tool - don't leave them in the drawer!

From experience, I stick with the Merc props - but part of the reason, admittedly, is that I have easy access to them. However, there IS a difference, where the "cheapie" props don't perform as well because of the lack of engineering that goes into them. I honestly couldn't tell you the difference just by looking - but from using them, yes.

However, before you spend any money - use those tabs more and you might find the 'fix' for your issue is a freebie... which is always a good thing!

 

[Chasing Limes]

So yours are the Michigan 14x18’s? What’s your WOT rpm?

Amazing what the correct prop can do. Like you, ours was night and day.

Correct Strecker 14x18 4 blade Michigan Wheels

 

[Chasing Limes]

So yours are the Michigan 14x18’s? What’s your WOT rpm?

Amazing what the correct prop can do. Like you, ours was night and day.

Best guess is 4600 rpm WOT. My tachs read differently, starboard engine is getting a new distributor this week and we will check for tach accuracy with the timing light then.

Cheers!