As a rule of thumb with the 330 and twin 300's, assume .85nm/G - 1.1nm/G depending on load.
26-28knwhat speed are you using for rule of thumb?
Which brand motors and what size props are you running?Mine is running about .6 a kn with a top speed or about 30. Starting to think props are wrong
I forgot the most important question - what are your RPMs at WOT?Which brand motors and what size props are you running?
Actually, I can’t even believe that’s right, even with wrong size props and they are definitely wrong. Are the motors trimmed all the way out at WOT a the stated 5000?Prop size?
You are WAY out of operating range for those motors. I believe you need to be at 5800-6000 with those motors.
As soon as Hurricane blows out of Fla, going for my 3rd set of props since March 2019, boat came with 15 inch SDS, changed to 17s good numbers,4200 RPMs 25.4 knts 4300 RPM 26.5 knts- 4700 RPM 30.5 knts, Had a 34 Pursuit and went to 4 blades big difference in rough water also on plane at lower RPM, trying 16 inch POWER TECH -4 BLADE THIS Friday ,will let you know the outcome, my 17 inch averaged about 1 MPG up to 5000 RPM turning 5500RPM TOP ,just under 40 knts, Looking for more bite and better control with the 4 blades.Dont know why my profile saids Express 265- mine is 2006 33 EXPRESS -F300 YAMs
I spoke with Marcus at PowerTech a little while ago. He confirmed what I thought. Keep the 16’s. He was blown away by the picture above. It represents 88% propeller efficiency. It looks like the 330 Express gets better mileage with 250’s then 300’s or 350’s. It is phenomenal fuel mileage at 1.41 mpg at 28.8 mph. I’ll give up the couple mph for the fuel efficiency since we are planning long range cruising. My top speed at 6000 is 36.6 mph . The 300’s hit over 40 and The 350’s will push the boat over 50 so there’s a huge difference at the top end but only a few mph at 4500 rpm.How did you make out? I just put Powertech 4 blade 16x16’s on my Suzuki DF250AP motors on my 2002 330 Express. I’m hitting 6000 rpm WOT trimmed all the way down with 150 gal of fuel and 15 gal of water and one 120lb passenger and no gear. If I trim up more then 5% I hit the rev limiter at 6100. I sent an email to Powertech to see what he thinks? I figure with full load heading off shore or cruising she should be just right. View attachment 9593