Are you referring to the boat on plane or idling? Idling with 350 mag's and fuel flow meters the boat loves to be in the 1700 to 1900 rpm range on plane mine likes 3600 rpm's. The 6.2's it is my understanding like 3500 to 3600 rpm's. Idling would be similiar.

 

Strictly an educated guess, but I would think that boat with V drives and the high reving engines would dictate a cruise in the neighborhood of 3800 rpms.

Doug

 

I cruise at 3500-3600 RPM at 23-25 mph (GPS) depending on wind and current. I initially get up on plane around 4000 and begin reducing thrust as the boat speeds up. I look at instantaneous fuel flow and attempt to lean out to 23-24 GPH depending on conditions. I boat on the St. Croix river. The boat does love about 3800 RPM but that is at the expense of about 2-3 GPH.

 

On Sunday morning at 7:00am, I left Bimini for Ft. Lauderdale with wind 4-8 knots; and following seas 2' or less. From the marina at Big Game, to Port Everglades, I averaged around 3650 rpm's and approx 26mph (max speed was 29mph). It took just about 2hours and 15 minutes, traveled 59 miles and used 64 gallons. Going to Bimini the Thursday morning before, we had choppy 3-5' seas, it took about 3-1/2 hours and I burned about 100 gallons....The conditions you run in sure make a difference.


Barry

 

I run 3600-3700 but the sweet spot does seem to be qt 3800rpm. When I swtiched to 4 blade props I noticed the performance at lower rpm and hole shot really increased.

 

What made you switch to 4blade, where did you get them, how much and what are the differences, not only positive, but negative in the 4blade vs 3blade.

Thanks

Barry

 

I'm getting to know mine as well. Ran today at around 3670RPM making 21-22MPH and burning 0.7-0.8MPG. I follow the same approach as Jimdavi. Starting off with 4000 to get out of the hole, then backing off to 3600 or so and adjusting the tabs. The best economical RPMs I found 1000-11000RPMs burning 1.5-1.7MPG running at 5MPH. Without a doubth, wind direction and sea conditions will change the numbers.

Alex.