Has anyone plotted this curve yet?

[FSH 210 Sport]

As to your boat test charts. A 255sd and a 255 fsh use sc engines the last number 5 instead of a 2 designates that.

Edit,,,, saw the chart said 252 your test said 255 sorry

No worries ! As I said in the other thread, I wish there were charts available to make the comparison apples to apples... especially testing the boats at the place and same atmospheric conditions. Temperature and especially humidity place a huge role in power production as well as efficiency.

One thing I did not mention is that Yamaha’s snowmobiles use turbo chargers on the engines that are the basis for the TR-1 engines ... having turbos on the TR-1 engines would be sweet! But there is the space required for turbos and inter coolers and especially the heat in that engine bay...

 

[Neutron]

I can say with 100% certainty that my 15 FZS svho and my wife's 18 EX deluxe will burn almost the same amount of fuel if i am just going at her pace. I always fill up every time i get out of the water and as long as i am not going off and ripping it up without her when i fill them both it is within 1/2 gallon in each.
So that is with a non ho TR1 and a svho

 

[Canuckjetboater]

1.8L NA vs SC fuel consumption vs speed. I’m curious if there is a cruising speed where the NA and the SC are close in fuel burn.

28 mph was a good cruising speed for my AR240 as far as fuel burn, 10-12 gph. Wondering the fuel burn for the supercharged engines at ~28 mph.

Thanks!
Mark

@McMark ..... regarding boats with engine/outdrive technology more horsepower may result in less fuel consumption with a lightly loaded boat but as soon as you start adding gear, people and speed you lose the efficiency of a less powerful engine and very quickly its x/y lines cross and you start consuming increasing amounts of fuel. I did not notice any difference when on my Yamaha SVHO cruiser and a friend was on his non-supercharged as long as I wasn't pinning the throttle or running at very high RPM. On this forum I have seen owners complain that they have (I believe one example) a 195 non-supercharged vs a supercharged 195 and the N-SC was complaining about top end with a loaded boat. I would much rather have a supercharged engine for towing sports and being able to carry a load (gear/friends) than a non-supercharged ..... if I was making a long run I would just build a really nice mini platform of say Starboard with a marine mat cover to put a couple of fuel cans on. In my boating life I have always sought as much HP and acceleration as was possible for my marine vehicles and NEVER regretted doing that. BTW, isn't mentioning fuel efficiency and boats in the same sentence forbidden?

 

[212s]

launching a surfer with 800lbs on the rear deck.

Whoa, that's one fat surfer! Tell `em to lose some weight!

 

[212s]

I can say with 100% certainty that my 15 FZS svho and my wife's 18 EX deluxe will burn almost the same amount of fuel if i am just going at her pace. I always fill up every time i get out of the water and as long as i am not going off and ripping it up without her when i fill them both it is within 1/2 gallon in each.

I don't think that's a relative comparison to boats which are much heavier and have much more drag in the water. The light weight of the jetskis makes the SVHO much more efficient. I'd bet your rpm is much lower than the EX at the same cruising speeds.

For some number, the twin BRP ACE motors with 300hp gobble fuel like candy as the rpms climb - cruises at 11gph which is fine, but WOT at 46gph. Copied from the Scarab website for the 215 and reformatted to fit here:

FUEL FLOW DATA - Twin Rotax 1.6L
5000 rpm 30 mph 11 gph
7500 rpm 57 mph 39 gph
WOT 61 mph 46 gph

That's a lot of fun at 61mph though.

 

[Neutron]

I don't think that's a relative comparison to boats which are much heavier and have much more drag in the water. The light weight of the jetskis makes the SVHO much more efficient. I'd bet your rpm is much lower than the EX at the same cruising speeds.

For some number, the twin BRP ACE motors with 300hp gobble fuel like candy as the rpms climb - cruises at 11gph which is fine, but WOT at 46gph. Copied from the Scarab website for the 215 and reformatted to fit here:

FUEL FLOW DATA - Twin Rotax 1.6L
5000 rpm 30 mph 11 gph
7500 rpm 57 mph 39 gph
WOT 61 mph 46 gph

That's a lot of fun at 61mph though.

You are right the ex is always running slightly higher revs than my svho

 

[Spg1582]

If you're talking about the new 25' FSH, then the best we can do is extrapolate. But in virtually every scenario I have seen, the SC engines suck down way more gas than the normal engines. Just look at the fuel burn numbers for the 27' boats last year. 40.8 gph at wide open!

Yamaha 275SD (2019-) | BoatTEST

boattest.com

Just took out my 255 fsh e for the recommended engine break in. Drove boat 90 min under 5k rpm. According to connext screen got 1.5 mpg. Hopefully that improves. Not enthusiastic about premium gas. With 76 gallons, 4 persons, and most of the gear 52 mph top speed. Flat calm on the lake. This is the 2022 model.

 

[mrcleanr6]

Thats about right for mpg. Thats what my boat gets at cruise

 

[212s]

Just took out my 255 fsh e for the recommended engine break in. Drove boat 90 min under 5k rpm. According to connext screen got 1.5 mpg. Hopefully that improves. Not enthusiastic about premium gas. With 76 gallons, 4 persons, and most of the gear 52 mph top speed. Flat calm on the lake. This is the 2022 model.

Don't pay much attention to the mpg unless you reset it while cruising as it's an averaged speed including idle and no-wake speeds. I think you can expect to see about 2.5mpg. Our best is 3.0mpg at 27mph and 5100rpm. Reset the Trip stats while cruising and look for the highest gph while varying speed slightly...the sweet spot is probably around 5000rpm or so and the mpg will peak.

 

[FSH 210 Sport]

Here’s the two magazine tests done by boat test and boating magazine. There’s a pretty big difference in fuel consumption between the two at WOT but they’re relatively close at best cruise. Boating gives some test data, boat test surprisingly has none, in the real world you’re going to have more gear, fuel, and people weight not to mention temp, humid and wind. I’d expect best cruise to be right at 2 mpg.

https://boattest.com/boats/yamaha/255-fsh-sport-e-2021

2021 Yamaha 255 FSH Sport E

Yamaha's 255 FSH Sport E has offshore capabilities with top-of-the-line performance

www.boatingmag.com

These are the fuel consumption graphs.

Boat Test: no testing data given



Boating Magazine: 40% fuel 250# crew weight..no atmospheric data given.

 

[mrcleanr6]

He has twin svho’s and a much heavier boat than yours. I dont think he is going to see much better than 1.5-1.6mpg. Mine is 1.6@5500 which is barely on plane and supposed to be cruise rpm. I usually run at 5900-6000 and the boat rides alot better, a few moh faster and only a .1 mpg hit bringing me to 1.5.

 

[mrcleanr6]

Actually that reply was meant for 212. The top chart seems more accurate to me. You can see he has the same thing goin on as i do. Cruise at 1.8mpg but with just a .1mpg hit he also gains 10mph. Doesnt make sense to me to run at 5000. If you truely want the best mpg i guess then yes run her at 5000 but i think the op will prob end up at the 6000 mark to gain the huge speed increase with next to no fuel hit.

 

[FSH 210 Sport]

Actually that reply was meant for 212. The top chart seems more accurate to me. You can see he has the same thing goin on as i do. Cruise at 1.8mpg but with just a .1mpg hit he also gains 10mph. Doesnt make sense to me to run at 5000. If you truely want the best mpg i guess then yes run her at 5000 but i think the op will prob end up at the 6000 mark to gain the huge speed increase with next to no fuel hit.

Your reply came in while I was writing mine…

Between the two tests on my boat I’ve found the boat test to be more accurate. I have more weight in my boat than in those tests and I’m at 5000’. Boat test lit’s my boat at 3.5 and boating lists my boat at 3.65. The best cruise I can get with stock impellers is right at 3.2 with three people on board, 70-80% fuel, trolling motor and batteries, gear etc… I think boat tests listed weight was 3703#, I’m realistically running around 4300#.