TOPIC:

This past winter I ordered a new Merc Spitfire prop for my 150 Fourstroke. It is an aluminum prop of the latest alloy and design. I read some positive reviews on it and of course the bad ones. Seems the complaints were not on performance issues but on the painted finish on some that wore off soon after being put into service. I normally run 3 blade stainless props on my boats and I have a 17 and a 19 pitch for the 150. Both work well but neither one keeps the hull on top of waves easily. The Spitfire raised the stern, gave me a drier ride and made the boat stay on plane at a lower speed. I also noticed it trolled almost a half mile per hour slower. The holeshot was better than the 17 pitch Vengeance and 19 pitch Laser II. It almost seems to jump out of the water. The Spitfire is a 14x17 pitch.
I bought aluminum because of the price and not knowing what to expect from it. It won't last like stainless but it would be a good upgrade for someone who just runs aluminum props. I'll wind up getting a 4 blade stainless prop one day after seeing the benefits of using one.

Don - did you lose any top end speed?

I can't answer that yet Dirtyx. The water was too choppy for me to completely air it out. With the engine tilted all the way down it ran up to gps 40 mph with some throttle left. My gut feeling is that it will be as fast as the 14x17 s.s. vengeance. Because it is much lighter in weight I think it won't lose rpm even though it has the extra blade in the water. I'll also mention that I did some fast turns and zig sagging and had no blowout and the boat stuck to the water like a magnet.

Don I think my wife is going to be unhappy with you because now I want to get a 4 blade and see if I get any improvement .

It seems like alot of improvement has been made on 4 blades in relation to the geometries and dynamics. Might lose a touch of high end speed but may be great for control and larger seas.

Dirty,

I went to a 4 blade and love it for Lake Michigan. It is about 2 mph slower on my pig than a three blade at wide open. The real benefit is at cruising RPM its 4-5 mph faster that the three blade. It also does better in the rough as it stays hooked up better and the boat will plane at a lower speed. Downside is the extra blade will increase your troll speed. I have a kicker so it doesn't really matter, but at idle with the 19" 4 blade 3.3 is pretty much as slow as I can go.

Sounds good. I dont care about losing a little off the top end - I get up to about 54mph. My boat is glass, and tbh I think it should be better in big water than it is. She digs out of the hole in a hurry, but min plane speed is about 19mph. The boat also seems to slap down over waves hard - wondering if the spitfire would help keep the bow up and not slap down so hard. my prop now is a tempest plus 21P 3 blade. I am going to talk with Merc to see what they think as well. The props overall are cheap, but still I am only going to buy one if they think it will be worth it.

I am glad you started this topic - good info!

If you decide to pull the trigger and get one, a good place to get it is a Merc dealer called Jaco's Marine. I have gotten several from them over the years and have always been treated well. Prices on their props are very, very competitive. Usually free shipping also. I am quite pleased with mine so far. My boat never rode that high and dry out of the water. Like Baron said the planning speed is much slower and has to be more fuel efficient.

Thanks Don - I will check them out.
Im excited. Ive always thought my boat was propped more for performance than handling but the question of was it just the boat design was always was in the back of my mind. It will be interesting to see what the Merc engineers have to say.

Call Bblades propellars. I actually raised my motor one hole to keep the bow from raising too high. Not necessary but in my case it made a huge improvement. I'm running a 19" revolution 4 and Fays Marina here in LaPorte has them for sale at the best price I have seen.