GPH for engines - Where is the info ?

[Big Al]

Where can I find a comparison of the gas consumption for the different boat engines ?
(eg: GPH based on Engine make-type-model, RPM) ?

 

[fc3]

There isn't any for gas engines. Merc won't publish the torque curves for their engines; they consider the data proprietary. GM on the other hand, who builds the engines, does. Weird. Diesel engine data can be found on the manufacturer's web site.

Now you can go to the various boat tests and look at their data. If the boat has the correct propeller, then the fuel burned @ RPM should be pretty close without regard to which boat it is installed.

Best regards,
Frank

 

[berth control]

Boating mag does lots of tests with different boats, you could look on their website to see similar boat/motor configs to yours or what you want to see.

 

[Southpaw II]

I received a CD from Sea Ray way back in 1999 or so that had data on every model / engine como. It had published speeds, props, and GPH for different RPMs. Pretty cool...I gave it away, and then later was able to get another, but SR acted like I was asking for something secret. All this to say that they provided the info at one time, but perhaps not now. I'll dig and see if I still have it.

 

[Southpaw II]

I received a CD from Sea Ray way back in 1999 or so that had data on every model / engine como. It had published speeds, props, and GPH for different RPMs. Pretty cool...I gave it away, and then later was able to get another, but SR acted like I was asking for something secret. All this to say that they provided the info at one time, but perhaps not now. I'll dig and see if I still have it.

OK, Al. I found the CD, dated 1999. Problem is, it's in that Sea Ray, tried and true "QuickTime" format, and I can't cut and paste sections from it.

In addition to the model spec info you would expect, there is info regarding prop sizes, cruise rpm/cruise GPH, and WOT rpm /WOT GPH. Gas and diesel.

If you have a specific question, I would be glad to help, or perhaps sometime later, I can enter the info into a spreadsheet so we can all see it easier.

 

[JV II]

Where can I find a comparison of the gas consumption for the different boat engines ?
(eg: GPH based on Engine make-type-model, RPM) ?

The Sea Ray cruiser and sport yacht catalogs have this info.

 

[Big Al]

Wow, thank you all for your effort to provide me the information....

....If you have a specific question, I would be glad to help, or perhaps sometime later, I can enter the info into a spreadsheet so we can all see it easier.

I would like to have the information for :

- Mine: A 1995 Sea ray 370 DA with twin 7.4 L (310 hp)

- and someone looking for a used 28 feet boat (could be a Sundancer) and asking if he should get a boat with one or two engines, what is the gas consumption, etc.... I would like to show him that the gas consumption would not be higher with a boat with two engines but I want to come with facts

The Sea Ray cruiser and sport yacht catalogs have this info.

Do you mean the brochure ?

http://www.searay.com/order_a_brochure.asp?cid=1729&formtype=1286&format=strict&modelid=43713&tab=2

 

[Southpaw II]

Wow, thank you all for your effort to provide me the information....



I would like to have the information for :

- Mine: A 1995 Sea ray 370 DA with twin 7.4 L (310 hp)

- and someone looking for a used 28 feet boat (could be a Sundancer) and asking if he should get a boat with one or two engines, what is the gas consumption, etc.... I would like to show him that the gas consumption would not be higher with a boat with two engines but I want to come with facts






Do you mean the brochure ?

http://www.searay.com/order_a_brochure.asp?cid=1729&formtype=1286&format=strict&modelid=43713&tab=2

This info is for 1999 only. The 310hp version was MPI.
Propshaft: A-19, 1.5", 73.19" long
Trans: V5000, 2.0:1
Prop: 18x21 3BC
WOT Speed: 34-38 @4600 RPM
GPH:10.4@3000rpm
27.2@4400

 

[fc3]

The fuel burn data for my boat, which has twin 7.4 is here.

Best regards,
Frank

 

[Tail Chaser 661]

Looking at Sea Ray specs.

Nice the 454ci burns less fuel at 3000rpm.
Then the 350 mag does at 3500rpm.

 

[Big Al]

Frank C

And based on this info, the 7,4 Horizon(380 hp) burns about 36% mores fuel at 3000 rpm than the standard 7.4 (310 hp)

Interesting

 

[VinceR]

Big Al,

Here is my info from computer attached to engines for fuel flow and GPS for speeds.
My engines are the same as yours so fuel flow should be the same at the RPMs. However your speeds will change from my 340 to your 370.

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

 

[fc3]

And based on this info, the 7,4 Horizon(380 hp) burns about 36% mores fuel at 3000 rpm than the standard 7.4 (310 hp)

Interesting

Yeah, but you're going a couple of knots faster. I test ran two new 340s before I bought my 330. (The 1999 340 has the same hull as the 1999 330.) One had the horizons and one had the standard MPIs. The Horizon engines ran a knot or two faster. I don't remember that well since it was 10 years ago. Didn't think the difference was significant enough. Most of the Horizon's power was on top end. So considering that the Horizon made more power where I didn't need it, that it burned more fuel, and that it was a GM 454 modified by Mercury I decided to get the 7.4 MPI rated at 310. The Horizon engines also tend to burn oil since Merc set up the pistons and rings on the loose side figuring that they'd heat up and expand when the engines are run hard. Yeah, maybe in a sport boat, but who pushes inboard cruisers to beyond 85%?

Best regards,
Frank

 

[Big Al]

Thank you for the information.

 

[jitts3]

I gave it away, and then later was able to get another, but SR acted like I was asking for something secret. All this to say that they provided the info at one time, but perhaps not now. I'll dig and see if I still have it.

They may not be willing to give it up because they are worried of the greenies making them a target. My GF used to work at the Cadillac/Chevy dealer. I asked them for the weights because I believe the heaver the vehicle the better the surviveability in a crash. GM hold that close to the vest because of the greenies.

I was told that back in the day if you asked about a boats fuel consumption they showed you the door. Again, thats what I was told.

Lets face it nowadays this is info you need, however industry pros FEAR the enviro nuts.:wow:

 

[Big Al]

..... However your speeds will change from my 340 to your 370.

3000 rpm 16.9 gph 24.0 mph .70 mpg 150 miles

Absolutely, at 3000 rpm I will do about 19 mph VS you at 24 mph with your 340.

 

[fc3]

They may not be willing to give it up because they are worried of the greenies making them a target. My GF used to work at the Cadillac/Chevy dealer. I asked them for the weights because I believe the heaver the vehicle the better the surviveability in a crash. GM hold that close to the vest because of the greenies.

Data on the IIHS web site backs up that belief. IIHS actually goes on record saying heavier is safer. www.iihs.org

I was told that back in the day if you asked about a boats fuel consumption they showed you the door. Again, thats what I was told.

I don't know. I always asked cruise speed and cruise fuel burn questions. Bought my first new boat in 1984. Do know how far back "back in the day" was.

Lets face it nowadays this is info you need, however industry pros FEAR the enviro nuts.:wow:

Probably true. Ford took a lot of heat for the Excursion from the greenies. When they were developing the longer wheelbase Expedition, they decided not to name it independently from the short wheelbase model, so not to draw the ire of the nut cases.

Best regards,
Frank

 

[VinceR]

Big Al,

Got this from Boat Test. 310 HP 370 Sundancer

Test Power: 2 x 310-hp MerCruiser 7.4L MPI ​

RPM ​

MPH​

Knots​

Total GPH​

MPG​

NMPG​

Range​

NM Range​

dBa​

1000
6.7
5.8
4.0
1.68
1.46
415
360
69
1500
8.9
7.7
7.6
1.16
1.01
288
251
73
2000
10.2
8.8
12.6
0.81
0.70
199
173
76
2500
12.7
11.0
18.0
0.71
0.61
175
152
78
3000
20.0
17.4
26.2
0.76
0.66
189
164
83
3500
26.6
23.1
38.0
0.70
0.61
173
150
85
3800
30.0
26.0
46.0
0.65
0.57
161
140
88

Sea Ray 370 Sundancer​

Length Overall​

37' 0

Dry Weight​

17,000 lbs.

Beam​

12' 7

Fuel Cap​

350 gal.

Draft​

2' 8

Water Cap​

70 gal.

Deadrise/Transom​

N/A

Bridge Clearance​

N/A

Max Headroom​

N/A

 

[VinceR]

Well that came out screwed up. You must read it straight down.

Example

RPM MPH Knots GPH MPG etc.
1000 6.7 5.8 4.0 1.68

 

[Big Al]

That is all I need.

Thank you.

PS: How did you get that info on the Boat Test site ?