fuel consumption query.sundancer 330

[The Maestro]

Sea Ray 330 sundancer 2001 with 7.4l v8 mercruisers.....what sort of consumtion should I reasonably expect at approx 3000rpm ? have tried and tried to get some info through various means ?
am averaging circa 30mph @0.90 miles /gallon gas.Am fairly new.

 

[Southpaw II]

Seems a bit optimistic....something in the .7 mpg might be a bit more realistic. BTW, SR didn't market a 330 DA in 2001. The boat in the US was a 340 DA. Is this an International model or an Express Cruiser.....V-Drives or Outdrives?

 

[CV-23]

I agree on the .7.....would love to have one though, Mike.

 

[tdschafer]

Let's see......I believe my burn is approximately 30 gallons per hour when cruising @ 3200-3300 RPM's. My speed is about 26-28 knots. If we use 27 knots as the mean, that equates to 29.7 mph. Thus, I burn 1.0 gallons per mile!!!

 

[Southpaw II]

The boats with the stern drives will be a bit more efficient since they run a little faster....

Todd,

Is your boat V-Drive or Bravos?

Don

 

[330DA]

I had a '97 330 sundancer. I got, same as Todd, 1.0 gpm.

 

[tdschafer]

The boats with the stern drives will be a bit more efficient since they run a little faster....

Todd,

Is your boat V-Drive or Bravos?

Don

Don,
I have V-drives. I should put that in my signature!!:smt021

Note: Updated my details!!

 

[dpmulvey]

OP is from Scotland. May still have been a 330 in Europe in 2001.

IMO, not enough information. What is the bottom condition? Are the props tuned? Salt or fresh water?

Isn't gasoline about 6 Euros per gallon in Scotland. I would be as concerned with miles per gallon as gallons per hour. At 3000 RPM you may be bogging down. I do not have 7.4's so cannot speak to the sweet spot for cruising.

My 2 pence.

 

[VinceR]

SEA RAY 340​

2001​

PERFORMANCE​

“WILD RICE”​

TWIN 454 MPI​

​

Speeds by GPS
Fuel Flows by computer connected to engines.

RANGE IS 215 GALLONS

RPM MPH GPH MPG RANGE

700 3.9 2.0 1.95 419

1000 6.0 3.6 1.66 358

1200 6.8 4.4 1.55 333

1500 7.9 7.0 1.13 242

2000 12.4

2500 18.6

3000 16.9 24.0 .70 150

3200 20.5 26.6 .77 164

3400 24.1 30.6 .79 168

3500 25.0 31.0 .80 172

3600 26.4 33.4 .79 170

3800 28.0 34.8 .80 172

4000 29.5 38.0 .77 164

4300 32.6 47.6 .68 147

 

[LTD.330]

Though the above mentioned performance figures are for a 2001 340, I'm sure everybody knows that hull and engine configuration is the same as the previous generation 330's. The big difference being about 1500+ pounds of weight.

With that in mind, my performance numbers are inline with the 2001 340. With full tab and running about 3400 RPM's I'm cruising flat around the 25-26 MPH. Maybe 24 MPH with full fuel and water. No way do I see nearly 30 MPH at 3200 RPM. In fact, I think my boat tops out around 31 MPH at WOT.

Also, my fuel burn is around 30 GPH @3400. Those numbers aren't even close to being scientific, just best guess estimate because I don't have fuel flow meters.

 

[tdschafer]

Though the above mentioned performance figures are for a 2001 340, I'm sure everybody knows that hull and engine configuration is the same as the previous generation 330's. The big difference being about 1500+ pounds of weight.

With that in mind, my performance numbers are inline with the 2001 340. With full tab and running about 3400 RPM's I'm cruising flat around the 25-26 MPH. Maybe 24 MPH with full fuel and water. No way do I see nearly 30 MPH at 3200 RPM. In fact, I think my boat tops out around 31 MPH at WOT.

Also, my fuel burn is around 30 GPH @3400. Those numbers aren't even close to being scientific, just best guess estimate because I don't have fuel flow meters.

LTD,
My numbers are no way scientific either. I've only had the boat 2 seasons and am going strictly by memory of five months or better ago. My RPM's may have been as high as 3400 but, I generally stay in the 3200-3300 range, I also have 4 blade props that the PO of my boat installed. I know this changes things from the stock props but, not sure how. I use the speed off of my Garmin 3206 which is usually in the 26-27 knot range. Again all of this is from memory!!:smt101

 

[Gofirstclass]

FWIW, My 1996 with 5.7's got right at 1mpg at all rpm ranges once it was on plane, and up to about 4000-4200 rpm's where the secondaries on the carbs opened up.

A friend's 1996 with 7.4L's got slightly less. He could run at a little lower rpm and maintain the same speed I did, but it did'nt give him any improved economy over my boat.

 

[VinceR]

My figures come from GPS speed with a computer connected to the engines measuring fuel flow, three men on board with full fuel. On half fuel tanks or less i see a small increase in speed at the same RPM.

 

[VinceR]

Our experience and use is over 300 hours on the engines in the last 2.5 years. We run with full tabs at about 3500 RPM when on plane. Our "cocktail speed" is at 1200 RPM. We enjoy "cocktail speed". We could be "trawler bums" at heart. With 5 dollar gas looming ahead we will see a lot of 1200 RPM cruising this year.

 

[tdschafer]

Our experience and use is over 300 hours on the engines in the last 2.5 years. We run with full tabs at about 3500 RPM when on plane. Our "cocktail speed" is at 1200 RPM. We enjoy "cocktail speed". We could be "trawler bums" at heart. With 5 dollar gas looming ahead we will see a lot of 1200 RPM cruising this year.

Why do you run with full tabs? I assume that means they are "down". I use full tabs to get on plane then put them up all the way when cruising. The boat stays on plane and the tabs can only slow me down at that point.

 

[gregkjones]

This was brought up awhile ago. Most of the people here with 330s are using full tab because the boat is so tail heavy. I know not all are but many said they do. I dont know how some people are getting better numbers with the tabs up. I wish I did. My 330 slows down markably if I reduce tab at any RPM less than 3800. I am actually putting on bigger tabs in two weeks because of this annoying problem. Full tabs does burn fuel but not more than running nose high. With the big tabs (read: the appropriate size for the boat) I can get the nose down and not run full tabs since there will be more planing surface back there. And yes, I have all chain at the bow, still tail heavy.

 

[tdschafer]

This was brought up awhile ago. Most of the people here with 330s are using full tab because the boat is so tail heavy. I know not all are but many said they do. I dont know how some people are getting better numbers with the tabs up. I wish I did. My 330 slows down markably if I reduce tab at any RPM less than 3800. I am actually putting on bigger tabs in two weeks because of this annoying problem. Full tabs does burn fuel but not more than running nose high. With the big tabs (read: the appropriate size for the boat) I can get the nose down and not run full tabs since there will be more planing surface back there. And yes, I have all chain at the bow, still tail heavy.

Greg,
That is very interesting. I will have to monitor my performance more closley this season. I don't run with the tabs down and I don't feel like I'm nose high either. I will mess with the tabs a little more and see if it makes any difference! Thanks for the reply!

 

[LTD.330]

I run full tabs for the reasons Greg mentioned. If I don't, then the bow rises and I have to stand to drive in order to see everywhere.

 

[tdschafer]

I run full tabs for the reasons Greg mentioned. If I don't, then the bow rises and I have to stand to drive in order to see everywhere.

Yeah, I find that very interesting. I'm going to Text the PO of my boat and see what he did. I can stand or sit when I run. I guess visibility is better standing but only because of the angle from the helm to the bow, not so much the bow to the water. I will definitely be checking this more when I start using the boat this season. :thumbsup:

 

[Carpedmman]

Ok, As twin 7.4L, Bravo III owner here I better chime in and say that the sweet spot on this set up is around 3200 RPMs. This RPM with 1/4 trim up and with no tabs down runs the boat at 32-34mph. Again, right around a 1 mpg.