Twins vs Single? Gas/maintenance
 

Ok so Been comparing the two, and curious what some of you guys that have had a single engine boat and moved up to twins thought?

I know twins will use more gas, but how much more? I mean if you drive the boat the same way, (personally drive it easy like a curser most of the time 3000-3500rpms).

Not twice, cause the motors are not working as hard as a single, but not the same? For me I can normally run a whole weekend on my normal spots, and stuff on 20 gallons of gas, on a single 454mag, in my 252. So hos much you think I will burn with twin 502’s or 454s?


Then there is Maintenance, this is not as big of a deal to me, yes twice the price, BUT for the most part one oil change a year, and an impeller, and fluids is not that big of a deal. That is if everything stays together internally and stuff. (although the cool fuel system pump was expensive)

Thoughts

When I moved from a single engine 502 24ft boat to a twin 502 28ft boat I guestimate the fuel consumption was about 25% more. It really didn't show up a whole lot in my pocket book, but I only put 20-30 hours per year on the go-fast.

I went from a 24' single 600 hp to a 30' twin 425 HP, and saw better average fuel economy with the twins. I can cruise at the same speed with less RPM and the motors are much less high strung. I would say it really depends on the size of the boat and the engines. Like texoma said, 2 502's will use more than one 502.

I really don't notice the increase in maintenance, but I do all my own work.

+1

We had a 1986 26' Nova II with twin 260 hp Mercs. In a 2 1/2 hour run to Put-in-Bay we consistently used less fuel than a 21' Liberator with a big block 460, regardless as to who set the pace.

Same boat you may see a slight increase in fuel consumption with twins. 25% seems reasonable.

Maintenance on the other hand.... That can get costly if you have higher Hp motors that require expensive scheduled maintenance.

Fuel is only a little more as stated. The motors are working much less and should last longer because of that. The response and low spead maneuverability is WONDERFUL! I will never go back to a single (short of a pontoon). Maint can be expensive depending on parts. Labor is not quite double if you have someone else do your work...

Go twins, you will be glad you did.

BUmping this old thread.

where talking about it in another.

25 foot boat with singel big block merc motor, vs 34 foot with twin Merc big blocks

(454,502, 496) what ever,., they all pretty close.

I have a 31 awesome cat with twins. I like the boat but if I was going to do it all over I would get a 26 to 27 foot cat with a single. Other then the fuel and routine maintenance, I have gotten to where I leave well enough alone. Some of the extra things I would like to do is always X 2 and that adds up real quick. I'm not rich and just feel I would be happier with a single. Like I said I like my boat but how my boat is, is pretty much the way it's going to have to stay. So if you choose to get a boat whith twins and have plans to make upgrades make sure you have the funds to do it. If your unsure about weather you have the funds and you know you want to do upgrades really think about what you want. If someone wanted to trade me my boat for a single I/O cat I most likely would. But that's me. And like I said I'm not a wealthy guy just an average guy with a decent paying job.

Single vs twin
 

I have had many twin and single engine boats. Personally once you experience a twin you will never be happy with a single again. The current boat that I have is a 270T Hallett, that is 27' with twin 377" Scorpion small block Chevy/Mercruisers. The twin small blocks is really easy on gas. Much more so than twin Big Blocks. I would say that it uses less gas than my last single engine 24' Campbell used with a single Big block.
The performance on this boat is almost identical to that of the 35' Fountain that I used to have (with twin 500 EFI's),only the Hallett uses about 20% less fuel. (but it doesn't handle rough water as well either), smaller lighter boat! I figure 15 gph cruising at 40-45 mph.
So if cost of operation is a major consideration look for a boat that has twin small blocks and I don't think you will be disappointed.
David

got a buddy with twin 350 in a donzi. not enough room. I dont see my self buying anything that does not have twin big blocks.... the reason i want to upgrade is room, and tolit, and stuff that does not show up until 33+.. and that size boat will suck with out 2 big blocks. haha.

just wondered How much worse.

My 32 AT with twin 502mpi's gets better mileage at a 45mph cruise speed than my 28 Pantera with a single 525SC(bumped to about 560hp). The AT will get 1.5mpg or more and the Pantera was about 1.25mpg.