I dont either unless you need that reverse..I don't see any advantage to a high thrust prop at all.
So how fast will it push it into a 40 mph headwind against a 2 knot current? There are times when you need to make sure that every last bit of HP is put into moving the boat forward. Under normal conditions, I hit hull speed at about half throttle. But last time out, I was at full throttle, the engine was turning about half speed, and the boat was only moving about 1-2 knots. I was running with the swing keel part way up for less drag. Straight down wind was lined with large rocks.wow. A lot of techy stuff for a boat that with the stock, factory prop on the Honda BF8 would push it to hull speed at 2/3 throttle all day. I don't see any advantage to a high thrust prop at all.
exactly 2 knots slower than 40 mph headwind with no current. Oh no.. current discussion again..how fast will it push it into a 40 mph headwind against a 2 knot current?
So what happened that other 0.00001% of the time ? Musta been a real wing-dinger !we had a 26c with a stock 8 hp Honda for 15 years, and 99.99999% of the time it was just fine.
No, the Mac weighs twice what my boat does, with considerably more freeboard. Looking at worst case scenario. Some lakes storms can develop rather quickly.exactly 2 knots slower than 40 mph headwind with no current. Oh no.. current discussion again..
Pointing out that you have a 4 hp with a boat that is about the same size. All this discussion is with closer to 10 hp on these fairly light boats.
I think one of walt's main points in his detailed analysis was that it's of some value to make sure you're able to get up to full engine speed. The motor, be it a 4 HP or a 9.9, only makes that rated HP when somewhere very close to full RPMs. If your motor was turning only half speed at full throttle, then your prop is too big. (Just like mine is.) I may only be getting the benefit of about 5 HP out of the available 9.9 HP because I can't get the engine up to the speed where it is producing full rated HP. So I want to find a prop, call it high thrust, that could consume full engine HP while turning at full speed.So how fast will it push it into a 40 mph headwind against a 2 knot current? There are times when you need to make sure that every last bit of HP is put into moving the boat forward. Under normal conditions, I hit hull speed at about half throttle. But last time out, I was at full throttle, the engine was turning about half speed, and the boat was only moving about 1-2 knots. I was running with the swing keel part way up for less drag. Straight down wind was lined with large rocks.
No, but that came to mind also. I'll have to look and see if there is a way to tell what it is. If not, i may remove the spark plugs and turn it over (with the cord) while in gear to see what it is...You have to take into account gear ratio also. All the my experience in this this thread is with 2.08. RPM in the range of 5000 to 6000 for full HP seems to be common with most of these outboards but the gear ratio varies. Slip calcs also take into account gear ratio. Do you know what yours is?
8.7 inches...Sumner, your 4-blade, 7-pitch is what diameter?...
I never responded to all of this, but thanks to everyone for letting me know what size props you are running!8.7 inches
Sumner