triple vs twin on gas consumption ?
 

OK ! I know!

Triple are sometimes more expensive to insure and not as easy to sell, triple maintenance...

But, I'M mixed between a formula 419 triple 500' running (not sure) between 75 and 80 mph I guess, and a 42 sonic twin 500's running I guess 65 mph.

cruising speed at 3500 in the sonic must be around 40 mph

cruising at 3500 in the formula must be around ... 50mph?

My question is: from point A to point B, at cruising speed, I'M I right thinking the triple would not be really more expensive to run than the twins? Full throttle I'm sure it would be more thursty, but at cruising speed???

or more simple question, how many miles a gallons does a sonic and a F419?

really?your buying a boat based on fuel economy,,,,,too funny

Triple is less than most People think,with the three everything is working less.

not really, unless triple are a pig on gas. I have nothing financed but sometimes I try not to throw money for next to nothing more. if it's one third more gas for the small difference in speed, it's not Worth it for me...

It is NOT a third more,more like 15 percent.

I thought I read a 525 uses 54 gallons per hour at wot. If a 500 is close to that, I guess 35 gallons an hour at cruise. Three motors working together I assume might lower that number a bit. Maybe 28 gallons times 3?? I have no idea, but as much ground as I cover on a weekend I know I wouldn't want the fuel bill.

Every motor will have a given consumption rate at any RPM whether it is in a single,twin, triple or quad configuration. What changes is the "cruise" MPH @3600 RPM (example) and with the additional power, top end! It really is a "catch 22"

It would be very interesting to see hard numbers of an actual burn rate/ performance #'s on a similar bigger I/O boat rigged with twins and trips.

Similarly, I know of a few 32 Skaters over the years that had Trip where the owners pulled the center motor. They couldn't really justify feeding the extra motor, hammering the center gearcase/failures for the few extra MPH on the topend when they primarily used the boat midrange with the odd top end run.

It does take more RPM/fuel to run these boats at a given cruise w/twins vs trips.

Test run both boats, the twins may feel that there is enough power and gives you what you are looking for in a comfortable cruise the way it's set up or just feel like a dawg compared to the trips....

You should find one of the Hustlers or Nortechs with the triple Yanmars you can cruise at 50 all day long getting double the MPG you will get with any gas boat. A lot less maintenance also.

The 426 Skater V is a sweet boat with the twin oil burners - performance, longevity and 1500 mile cruise range. You would only have to fill it up once per season - LOL.

Surprised it took so long to find a home..unless it was because it had no cabin?

In theory SORTA but not completely true, lets talk fuel injection-Your fuel tables that control injector PW are MAP/rpm based and we all know it takes X # of lbs of fuel to make X horsepower. A boat with twins lets say at 60mph turns 4000 rpms at 90 map, lets say the PW at 4k/90 map is 10 ms per revolution so injector is open 2000 times for 10 ms every minute -20,000, for sake of discussion lets say that equals 100 gallons per hr of fuel x 2 motors=200 gph. Now lets say the same boat has triples, IT cruises at 60 mph at 3600 because there is less load per motor but it has 1 size bigger props, even if with the bigger props it was loaded to 90 map in fuel table at 3600 lets say PW at 90 map map is 9.5 MS and because its only turning 3600 its only , injector 1800 times a minute. 1800X 9.5 MS= 17100 vs 20,000 , 14.5% less fuel per motor. So lets go back to our pie in the sky number of 100 gph at 20,000 injector pw, 17100 is 14.5% LESS. so that would equate to 85.5 gph x3 =256 gph vs 200, yes the triple use more and will never match the fuel use of the twin but we are talking only 22% more because each motor is using only 85.5% as much as they would in the twin application. Now I just sorta put these numbers together, no, neither one will use 100 gph but percentage wise it should help you understand that motors DON'T necessarily use a set amount of fuel to goo a set rpm. Lets take it a step further and say you propped the 2 boats identical so they even turned the same rpm's, the triple would be loafing along at same rpm BUT would fall into a lower map table, probably between 70 and 80 map, the pw would be closer to 9 MS vs 10 and that would equate to 10% less fuel per motor so again you would be using 90 gph vs 100 gph per motor, so 270 gph vs 200 but still not 50% more, only 35% more, I hope this gives you a better idea, Smitty

I was going from the KISS approach in that you still have to feed a third motor but recognizing you are no longer running at the same RPM for a given MPH (not complicating the issue with the difference in prop pitch) from twins to trips.. As you gave the mathematics in detail - your efficiency and therefor fuel demand is not the same between twins & trips......That's a he11 of an exact answer ArticFriends - TY!

I will add this too though, at wot the fuel use IS going to be 50% more SORTA because once a motor is at wot it will be at same rpm and map if propped right twin or trip, the only thing that still would make it slightly less than 50% extra would be IF you were going from point a to b at WOT with trips you would have higher mph so using the 100gph analogy if it took you 55 minutes vs a hr to cover the same ground at wot at 300 gph vs 200 it would be slightly less than 300 as you only took you 55 minutes vs a hr but that would be splitting hairs, you would definitely see the gas gauge going down much faster!!!

but then again, you can't really put a value of the cool factor of trip's if you can afford them - LOL

To me it would be a giant PIA unless I was driving back and forth to Bermuda or Bahamas or something!

+1..... Also consider some triple engine boats won't plane on two if loaded/full of fuel!

I would not recommend a triple unless you boat in the ocean or great lakes where u can get in trouble if one quits and boat wont plane on two. I have owned 2 so speaking from experience, yes they burn way more than twins boats are very heavy also? They are very difficult to sell. Triples do have their place, really depends on where u boat

As an actual triple owner with experience, It is NOT just simple fuel consumption that you have to look t between the twin and triple. First you have to compare the engines. Example, ours had 496 HO's, the comparable engine in the speed in a twin would be 575's. That being said, the 575's will use substantially more fuel than the 496 HO at both cruise or WOT. But the real savings in the triple configuration is over all wear and maintenance. In the triple, you are using smaller power to achieve the same speed as in a twin. Thus less breakage in wear items, especially in drive wear. Oil changes and general maintenance are a few dollars more per year, but that is minor for what you will save in costs when dealing with your complete drive line.

One constant I have learned though in the last number of years, all the experts of why not to have a triple have came from those that have never had them.

I would NEVER EVER buy a boat with triples.

Insurance, no- resale, usually they are XR boats, get twin with 6's any day. You get 10% more performance for 50% more expenses. There is a reason why they are cheap. Remember you only know how much something costs once you resale it.

Which triple Boats have You owned?

+1

Everybody who HAS OWNED them, seems to make the same claims. I'm not the least bit scared of trips...

Nothing to be scard of, trips have their place.,but there all several things to consider. I had both a bravo boat and a 6 boat. My preference would be a twin 6 boat? Over either triple

None thank god...

Big surprise that was.

Did I mention?: One constant I have learned though in the last number of years, all the experts of why not to have a triple have came from those that have never had them.

Ok.....I'm in....
:food-smiley-007:

on the other hand... any twin with number 6 for sale in the 50 to 70k range? I doubt, so it might be a solution to run 80 mph without spending 100k plus...

Two engines are hard enough to work around............. 3 I think would be just a little more funner..... I think I could handle trips also........... Especially if its a 47 apache. :)

I've had a couple boats however. But your right what the f@ck do I know.

That last one was only a twin but I had five engines for it. Does that count? Actually now that I think of it I still have three of those five engines... That would make me a triple owner wouldn't it?

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http://www.youtube.com/watch?v=qWezQgnhGok

Never owned trips. Not scared of the fuel consumption at all. Already have side by side twins an they are a pia to work on. Would hate to climb over one to work on 2 more. Haha

I still think some are still missing a MAJOR point. You are using smaller engines to achieve the same speed as the LARGER displacement/HP twins. I Think everyone can agree 6's are by far the preferred choice on an open budget, but in order to turn those drives you need BIG power, which requires WAY more mechanical ability, including more in depth maintenance and of course WAY deeper pockets overall.

As far as cost of boat, here is a secret, A TRIPLE BOAT IS CHEAPER TO BEGIN WITH!!!!!

When we ordered our Baja in 07, We looked at ordering it with Twin 525's or the Triple 496's. The Twin 525 set up was $17,000 more than the triple 496's and guess what, the 525's were 6mph slower. As I stated earlier, you would have had to step up to 575's to get the same speed, ie: More original cost yet! So a triple boat may appear to cost less on resale, but that is only a relative factor, because they were less to begin with...

Just to recap: I am NOT saying, those that have added LARGE triple engines to their boats are not experiencing a higher cost, BUT even if you ran triple 575's, you need to run 1075's or better in a twin to get the same speed... The numbers change, but it is still the same ratio. Bigger is always better.... Until you have to pay to keep them running...

As far as working on a triple boat, there was plenty of room top climb around in the bilge. the only real issue was working around the exhaust from the front engine. No matter what boat you are working on, there is never enough room for us "larger" people...

Now You have posted pictures of twin engine boats in a thread based on triples,good one,and to add the picture of C4 Corvette?priceless,I see You have a 46' Azimut,which is a knock off of a Bayliner motor yacht,and I know this cause a guy I knows brothers friend owns one and he said so.:lolhit:Here is a pic of a bayliner.

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I would go triple on any of those two boats, less drag on the bravos also,looks like this is going to become a nut slinging thread I got this you got that. what happened to the days where everyone could get along . same thing at our lake guys go out and buys a huge boat thinking there the ****, guys like us wish we had the money to play, ive got a big step 42 fountain and I will park rite next to a 16ft runabout any day of the year, I don't care what they drive as long as they don't think theyre beyond everyone

Stellar display of knowledge there. Have fun selling your triple when you get there. I'm done with you lightweight.

So lot Me get this right,a Guy posts a question about triples,I Own a triple and spoke of the first had knowledge of owning one as well as owned twins in the past,You on the other hand post a picture of Yourself in short shorts standing next to a C4 vette with an overloaded jacked up 1/2 ton short wheel based truck and then post a transom video of a twin engine cat and I'm the dumb one?:lolhit:

Never had them but its obivously triple the annual maint, and I am sure insurance and resale will be tougher on you. Another thing is you hit something your talking three props, three drives that could get torn off. I went from single to twin, and I always find it PITA to have to do two oil changes, change two on this, and that. Just my thoughts.

OOOOOOOOOhhhhhhhhhh he said short shorts LOL:party-smiley-004:

Keep your eye out I think you can get a deal...

http://www.offshoreonly.com/forums/g...ip-500efi.html