4.3 EFI 220 HP Mercruiser in Bayliner 2455

M

moondarra

Well-Known Member
Joined
11 Apr 2005
Messages
849
Location
Southport
www.go2woodlands.co.uk
Has anybody got performance figures (RPM:speed:fuel consumption) for this engine/boat combination?

The Bayliner manufacturer's site only has the details for the 5.0 litre 220 hp engine.

It would be nice to have an idea of relative fuel consumption at different speeds.

Thanks! if you can help.
 
they aren't going to be masively different - if the FI engine is a little more efficient then you will see the improvement across the range and probably at tick over speeds you may see a difference. Additionally the installation will be a bit lighter. At given boat speeds you require a given HP, which requires a volume of air throught the engine which requires a given amount of fuel............
If you want comparisons of this sort go to the US sites where you will be able to look at a pretty close match - try here for example.
 
very crudely,3.0l 4.3l and 5.0l will use 5,7,10 galls per hour. But of course the actual boat and how laden it is with toasters and other essentials will alter this. It really comes down to how heavy you are on the throttle. Last 10pct increase in speed can account for doubling of fuel consumption. Have alook at that boat test web page, and tab to the results. Power/consumption curve may not be quite the same, but the picture drawn is quite sobering,!! I think that its also where theory and reality may drift apart- you re more likely to find the comfortable speed on the day with an eye of consumption, than decide on a consumption, and then put up with the ride.
 
I\'m not happy

I have to take exception to your flippant comment about the toaster. It is not the toaster, it is the two generators one takes on board to power said toaster (second one is obviously safety backup in case the first one fails) that add the weight to the boat. /forums/images/graemlins/smile.gif /forums/images/graemlins/laugh.gif /forums/images/graemlins/smile.gif /forums/images/graemlins/laugh.gif /forums/images/graemlins/smile.gif /forums/images/graemlins/grin.gif /forums/images/graemlins/smile.gif
 
how do you get a 220hp 5.0l using nearly 50% more in the same boat as a 220hp 4.3l - even crudely?

here's the figures for the 5.0l in the 245(US gallons of course)
Bayliner245-chart.jpg


can't get them for a 4.3MPI in boat that but the above break down to 10.7 gph at 3500 / 20 at WOT and for a smaller, 21ft bowrider, the figs for the 4.3MPI are 8 gph at 3500 and 17gph WOT - expect them to get closer to the 5.0 on a 245.
Again all US gallons.

Having a good cruising speed at 3500 giving pretty good economy the 5.0 looks well suited to the boat IMHO.
 
Toasters

[ QUOTE ]
It is not the toaster, it is the two generators one takes on board to power said toaster (second one is obviously safety backup in case the first one fails) that add the weight to the boat. /forums/images/graemlins/smile.gif /forums/images/graemlins/laugh.gif /forums/images/graemlins/smile.gif /forums/images/graemlins/laugh.gif /forums/images/graemlins/smile.gif /forums/images/graemlins/grin.gif /forums/images/graemlins/smile.gif

[/ QUOTE ]

Sorry, I don't have a toaster : does a George Foreman grill count?
 
[ QUOTE ]
At given boat speeds you require a given HP, which requires a volume of air throught the engine which requires a given amount of fuel............


[/ QUOTE ]

Thanks Duncan for your advice. I have already got the table you kindly posted for the 5 litre Mercruiser: but my boat has the 4.3 EFI engine and basically I was wondering firstly whether the performance curve was the same: ie is 3500 rpm the most economic setting, and secondly what improvement in mpg the eletronic fuel management gives compared to the carburettor fed 5 litre.
 
I would expect the curves to be very similar for these engies in the same hull - WOT is 4800/4900 etc etc

The fuel injection will give you better starting and it's enabled them to get more hp out of a lower CC engine - you want fuel efficiency too?!?
 
You say 5.0 l at 3500 is 10.7gals, and 4.3l at 3500 is 8 gph ? And I said 10 and 7 as a benchmark, being non specific on boat make and model ?I mean who care s about 1 gph in a petrol driven boat- it swallows the damn stuff anyway!! Am I misunderstanding you, or are you being pedantic? My main point was that the volume of the engine will of course have an effect on the engines consumption, but in reality you are more likely to adjust the cruising speed to the day and sea conditions, rather than set your speed by a chart from boattest. That is, its sort of interesting to know in the back of your mind, but out on the water, other emotions take over
 
[ QUOTE ]
and for a smaller, 21ft bowrider, the figs for the 4.3MPI are 8 gph at 3500 and 17gph WOT - expect them to get closer to the 5.0 on a 245.

[/ QUOTE ] is not the same thing at all. You highlight the effect weight will have and as the 245 is probably nearly double the 21ft bowrider I still expect the two units to get pretty close.
My experiences are that sea conditions do indeed dictate your range of options but that consumption curves also figure significantly in most peoples cruising speed selection - as you have already said they swallow it and it's expensive.
Finally these are US gallons so the UK figures are going to be more like 7gph at cruise for either engine - give or take 1gph!
I don't think I am being pedantic - I fundamentally disagree with the view that there would be a significant (you defined this at around 1gph) difference in the consumption experienced between these 2 engines in the same boat driven the same way.

Taking things to the extreme you are suggesting that an F1 engine will give better mpg than fords 2 litre lump in a mondeo........... /forums/images/graemlins/crazy.gif
 
You must log in or register to reply here.

Share this page

Top