4 blade vs 3 blade

minnesota

Anyone running a 280 with 496 cid ,bravo III and 22" pitch 4 blade set up? I'd like to know if you like them,  what kind of performance are you getting?

Michael T

To all guys thinking of swapping props: I made this comment a few years ago on this forum so to those who have already read it, my apologies. I do not know if the following applies to twin props as in Mercury B3s or Volvo Duoprops but when I was trying different props years ago for Alpha and bravo drives I found a number of marinas who would let me test props either for a flat fee or no fee if I actually bought a prop. the only condition was if you dinged it you bought it. This was a great feature for me as I got to try-out all kinds of 3 blades with varied rakes and pitches as well as 4 and five blades. one thing I learned for sure the right prop can take your boat from good to amazing in a heartbeat. Another thing I learned was to make sure the "new" prop I was trying did not over rev as few conditions hurt a stern drive or an engine's internal components  than a wildly spinning prop that is over revving and breaks free of the water. If I was thinking of re-propping I ask around at marinas and prop shops to see if they still have that loaner plan.

pepmyster

I was also thinking about using 22 pitch for our 280 also with the 496 , love to know also if someone tried this.

MarkB

I have a 260 with 22P.  I think it is a great match.  With 2 people on board, full fuel, full water, plane time is probably 8 seconds or less. I can plane with 10 people on board, full gas, full water in about 18 seconds. Trim tabs down obviously.

I am at 30 mph, 4200 rpm. Gas economy is 2 mpg at this speed/rpm.

Michael T

I'm going to run some numbers now that the weather is hotter and more humid but when I ran rpm versus mph in the spring with colder denser air the numbers were staggering (as in good) and reinforce what Al has said and I have always believed - get the biggest block (within reason) that will fit into your boat as it will not only plane faster and last longer but will give better all round performance and mileage. This spring my twin 502s powered the EC 360 with normal loads (for us) at 3300 rpm 32-33 mph, at 3500 rpm 34-35 mph. That's pretty amazing imo. At those speeds I was getting 1mpg or better. I have been in and talked with owners of 350s and 360s with 350 magnums ( imo ridiculously small engines for a 360) and 377s which performed better but still ran way up their engine rpms to stay on plane with a load and took a week to get there. On top of this the 350 with the 377s drank 10 gallons of gas more per hour than my 360 with twin 8.2s. Of course I paid a lot more for the 8.2s but that's because I didn't want to grow old getting onto plane. My point is that you can only do so much with a propeller or trim tabs. If a boat is underpowered you're still scr*wed. Get a big engine!

jme097

Twins 8's? Jesus LOL. I get your point. 

MarkB - Are you running a 6.2 in your 260?