underpowered and frustrated

M

Mutual Fun

New Member
Sep 28, 2010
22
Sault Ste. Marie, North Channel Lake Huron
Boat Info
2003 340 Sundancer(SDA), 6.3MPI-V, RayC80,2K Dome/GPS
Engines
6.2L MPI V-drives
Looking for advise from someone who has a 2003 340 Dancer (SDA) with the 6.2L V-drives.

The problem:

Poor responsiveness/handling at idle speed (docking....forget it if it's windy!)....poor top end speed relative to RPM....with the throttles all the way down the boat actually produces 5200-5300 RPM (engines are screaming) but only producing 36 MPH...4000 to 5300 RPM produces very little additional speed.....I think I want new wheels or modify my old ones......in my oppinion these props don't have enough bite. Thoughts?
 
You are underpropped if you are getting 5200-5300 rpm. This assumes you have accurate tachometer. The WOT for my 6.2L engines for comparison is 4600-5000 rpm which is stamped on them. I get 34.4 mph at 4840 rpm with a clean bottom and 18x18 4 blade props. Increasing you prop pitch would most likely give better top end speed and get your rpm into the recommended range again assuming your rpm readings are accurate. My advice is validate your tachometer first and if accurate talk to a prop shop about getting your props scanned/tuned or replaces. I just replaced my props with Michigan Wheel DQX 4 blade 18x18 nibral props. With your bigger boat you might need something slightly different.
 
True - underpowered and not enough bite. Make sure your RPMs are accurate, then take your data to a professional prop shop to have more bite put in the blades and perhaps some cupping. They should know what to do. Also, have the Sea Ray stats ready - the way they recommend the props to be. Also, know what your max WOT RPMs should be. Good luck. I'm really surprised you're getting 36 mph - that's not bad in this boat, if it's the new 340 (changed in 2003 1/2).
 
Hampton said:
.......I'm really surprised you're getting 36 mph - that's not bad in this boat.....
Click to expand...

+1. That's a great WOT speed number with 6.2s --- in both the new AND old 340. I bet some 320 owners would like to see 36 mph. I agree with the others that prop work should take care of your problem and give you better planing & cruising performance, and get those RPMs down. Hopefully, you can keep that 36 mph top speed number.
 
Mutual Fun said:
Looking for advise from someone who has a 2003 340 Dancer (SDA) with the 6.2L V-drives.

The problem:

Poor responsiveness/handling at idle speed (docking....forget it if it's windy!)....poor top end speed relative to RPM....with the throttles all the way down the boat actually produces 5200-5300 RPM (engines are screaming) but only producing 36 MPH...4000 to 5300 RPM produces very little additional speed.....I think I want new wheels or modify my old ones......in my oppinion these props don't have enough bite. Thoughts?
Click to expand...

This is a f*cking joke... right?

Give me a break...

"Yeah... You should b!tch some more about that poor performance.. you are cool."

Did the "boating crowd" leave CSR? Are we just left with a bunch of 19 year old idiots now?
 
Four Suns said:
This is a f*cking joke... right?

Give me a break...

"Yeah... You should b!tch some more about that poor performance.. you are cool."

Did the "boating crowd" leave CSR? Are we just left with a bunch of 19 year old idiots now?
Click to expand...

36MPH is about my max with a lighter boat. The 6.2's are a bit more powerful but not that much. You should be right where you should be but I would verify your RPM's.
 
Mutual Fun said:
Looking for advise from someone who has a 2003 340 Dancer (SDA) with the 6.2L V-drives.

The problem:

Poor responsiveness/handling at idle speed (docking....forget it if it's windy!)....poor top end speed relative to RPM....with the throttles all the way down the boat actually produces 5200-5300 RPM (engines are screaming) but only producing 36 MPH...4000 to 5300 RPM produces very little additional speed.....I think I want new wheels or modify my old ones......in my oppinion these props don't have enough bite. Thoughts?
Click to expand...
You could tweak the props a little if your truly hitting 5,300rpm but other than that it sounds like your boat is right on the money.
 
Is this your first boat? or your first boat with inboards? Did you do any research before buying it? If you want a go-fast cruiser you should have purchased a Formula SS. http://www.boattest.com/boats/test_results_PrintP-e-oem.aspx?id=1870

If that isnt fast enough you should consider a Skater. http://www.skaterpowerboats.com/

models30


Your numbers line up pretty close with Boat Test reports and they tested using big blocks. There doesn't appear to be anything wrong with your boat, the problem is with your expectations.

http://www.boattest.com/boats/boat_video.aspx?id=75#Test-Result
 
Four Suns said:
This is a f*cking joke... right?

Give me a break...

"Yeah... You should b!tch some more about that poor performance.. you are cool."

Did the "boating crowd" leave CSR? Are we just left with a bunch of 19 year old idiots now?
Click to expand...

This unfortunately is just plain rude and I am sure some of us 320 and 340 owners that responded don't appreciate being referred to as idiots. If you were trying to be funny your humor was at lost at least on me.:smt009
 
Rip out the 6.2s and drop in some 8.1s. Maybe a nitro tank too.
 
EricW said:
....I bet some 320 owners would like to see 36 mph.....
Click to expand...

You just lost your bet. My 320 (with 5.7L and VDs) does 35mph at WOT with full fuel and full water. The RPMs are right to the specs and I'm very happy with it. I could care less about 1 extra MPH as I stay there for only a min or two twice a season to make sure the boat performs to the specs. For everything else it's the comfortable cruising speed of 25-27mph. If you need to go 36mph all the time you've got the wrong boat.
 
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Funny thing... I have not seen how fast my boat goes at WOT. I have gone 31 MPH at 4000 RPM, but I have not yet pushed it to WOT... I will have to try that this week end... I have new SS Hi-TEK headers on my 340, and only 1/4 tank of gas... I bet I can get 38 MPH... Alex, maybe we can have a race??? Looser buys... Its good to have a mind of 19 year old:thumbsup:, I only wish my body was only 19...:smt043
 
rcknecht said:
Funny thing... I have not seen how fast my boat goes at WOT. I have gone 31 MPH at 4000 RPM, but I have not yet pushed it to WOT... I will have to try that this week end... I have new SS Hi-TEK headers on my 340, and only 1/4 tank of gas... I bet I can get 38 MPH... Alex, maybe we can have a race??? Looser buys... Its good to have a mind of 19 year old:thumbsup:, I only wish my body was only 19...:smt043
Click to expand...

I am assuming you have 380HP from those old big blocks so you just might be able to do it. The 454 in my previous boat was only 310 HP. A fellow at my marina with a 1998 Maxum 3700 bought his boat specifically to get your engines since he was told by someone in the know that for that year they were better than the 8.1s since they had dual overhead cams I believe. I hope yours are not as noisy as his at start up. It sounds like we are at a NASCAR track.:grin:
 
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I am assuming you have 380HP from those old big blocks
Click to expand...

Rod has the previous generation 340, which is essentially built on the hull of the 330 that it replaced in SR's lineup. As such, his boat is lighter, narrower and shorter than the 340 incarnation that the original poster has. I'll bet Rod does get up to and over 36mph with a light load and he'd likely beat Alex in a race. About all I could do in that race would be shoot the starting gun!
 
320Bob said:
You are underpropped if you are getting 5200-5300 rpm. This assumes you have accurate tachometer. The WOT for my 6.2L engines for comparison is 4600-5000 rpm which is stamped on them. I get 34.4 mph at 4840 rpm with a clean bottom and 18x18 4 blade props. Increasing you prop pitch would most likely give better top end speed and get your rpm into the recommended range again assuming your rpm readings are accurate. My advice is validate your tachometer first and if accurate talk to a prop shop about getting your props scanned/tuned or replaces. I just replaced my props with Michigan Wheel DQX 4 blade 18x18 nibral props. With your bigger boat you might need something slightly different.
Click to expand...

BOB, Please help me understand why SEARAY would put under propped props on one of there boats?? How does one know if he/she should should get biggger/more blades? props, if one is going to pay over 250 K on a boat he should have the right props, what am i missing???:huh:
 
320Bob said:
I am assuming you have 380HP from those old big blocks so you just might be able to do it. The 454 in my previous boat was only 310 HP. A fellow at my marina with a 1998 Maxum 3700 bought his boat specifically to get your engines since he was told by someone in the know that for that year they were better than the 8.1s since they had dual overhead cams I believe. I hope yours are not as noisy as his at start up. It sounds like we are at a NASCAR track.:grin:
Click to expand...

I don't think so :smt018 you may want to find someone further "In The Know" for engine advise.
 
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