djam":2yfif4hy said:
I need to do more testing, but right now I'm not getting what I expected from the boat. It comes out of the hole awesome and generally starts planing about 20-22mph. I've taken it to WOT a few times and running about 5400rpms and 43-46mph according to GPS in moderate seas. I thought the top end would be closer to 5800 or 6000.
Now for my question because I don't really run top. At cruise at 3900-4000rpms I'm doing about 25-27mph, but burning 1.6mpg or 1.9 according to the built-in gauge. The GPS speed and Yamaha speed are almost identical. At 4200rpms I get 26-29mph. Same 1.6-1.9mpg. Some of my friends are getting 2.1 to 2.4.
My load is a full tank (i'm usually doing 160-200 miles) at 137g, 4 guys with a total weight of about 800lbs, 65-gallon bait tank with 2 scoops, and probably 50/60lbs of ice plus fishing gear. I know that is a lot of weight, are my fuel numbers reasonable for this boat? MOst of the people I know don't have th 300hp engine, they are running 250s.
Boat:2017/ 2320 no bottom paint
Motor: 300hp Yamaha
running the local waters in southern California.
Different model year and different motor but here is my two cents........ Have had my 2008 2320 with a F250 for over a year and a half now, believe the new 300's may be lighter in weight than the older 250's.
I usually run a very heavy boat as you do, full gas tank, 4 guys, live well, gear, ect..... My motor came with the stock 19p black painted stainless which is a decent prop for a much lighter boat.
Boat always felt that the motor was dragging and the hole shot wasn't the best so I installed an SE Sport 300 and raised it 2 holes last year which made a good difference overall but the more load on the boat I was only seeing 5300-5400 max rpm and the boat was a dog in the mid ranges.
Worked with my local marina a new prop last week, went with an OSI 4 blade 17p and wow what a difference. Better hole shot, cruise mpg up .3/.4, boat feels like a go cart now in the mid ranges, excellent throttle response between 3500-5000 rpm. Can trim the motor more now and can turn 6100 rpm light and 5800 rpm heavy. Feels like a different boat. Did lose about 2 mph on the top end but don't need to go that fast.
Also if I'm not running offshore I usually keep the gas tank 1/2-3/4, no need to carry all that weight around.
Some numbers from this past weekend with 3/4 tank of gas, this was in the bay and a flat ocean.
1 person
Top rpm - 6100
Cruise - 4500, 2.6/2.7 mpg, 26-28 mph.
2 persons
Top rpm - 6000
Cruise - 4500 2.5/2.6 mpg, 26-28 mph.
3 persons with gear, ice, full live well, ect.....
Top rpm - 5800
Cruise - 4500 2.1/2.2 mpg, 25-27 mph.