OUTBOARD PROP SELECTION

[Everclear]

I have a 2001 mercury 75hp on a 16' Alumacraft. The max hp. rating for the boat is 80hp. I am currently running the stock prop. I want to gain top end speed, low end is not a concern. What prop do you guys recommend?

Thanks for any input.

[DTro]

The prop should be matched for the boat. It's different for each situation/boat. Your biggest concern should be your RPM range at WOT (wide open throttle). You don't want to be over or under RPM. Choose the prop that matches the recommended RPM of the manufacturer. Now, if you don't have a tach that could be easier said than done. If you don't have a way to measure the RPM I would probably stick with what you have.

[ewirz]

I have a '98 75hp merc. on a 18' Alumacraft (80hp max). I had to replace the prop when I bought the boat. I went to the mercury web site and used their prop selector. It said max rpm was 5200, should use a 19 pitch prop in 13". That's what I put on it. Runs right about 5100-5200 rpm. Top speed (with just me and full tank of gas) around 36-37 gps. With three guys and fishing gear, about 32. I would imagine with a 16' boat (being lighter) would be a bit faster, though might have to watch rpm's. Hope this helps.

ERW

[hitthebricks]

Try a SS prop, it is a world of difference and worth the money HTB

[Deitz Dittrich]

A stainless as mentioned will outperform a alum. Finding the right pitch will help too, as stated do not go over your suggested RPM.

Try to take as much out of your boat as you can, and put all the heavy stuff you do keep in the furthest back of your boat. Believe it or not, this is huge for top end speed.!!! HUGE!!!!

[Everclear]

Thanks guys! I was able to find a stamping on the prop... it is a 13" 19 pitch so my only choice maybe a stainless in the same size. Do stainless props realy give you enough performance increase to justify the cost? I too am running around 37 mph gps and would like to get over 40 mph

[VMS]

Depending on what prop you choose, you may see an improvement, or you may not.... In a general sense, going to a steel prop in the same pitch and diameter will drop your RPM's a fair amount...something like 200 or so...could be more if the prop is more of a performance prop.

What I have found on the stainless prop I chose was the same RPM, but much better bite. I have a yamaha 90hp which I run a 13-1/2 x 17 Michigan Wheel Ballistic. When I switched from my stock 13-1/4 x 17 aluminum, I did not lose any RPM after moving the motor up a hole. Faster too...

My 90hp now breaks 40, but there are other contributing factors to that as well, like a manual jackplate and raising the motor higher.

Lots of variables...but if you want more speed, you will compromise your hole shot to an extent. At a minimum, get a more aggressive prop than the stock steel replacement, raise your motor a hole or two on the transom, and you might be able to tick 40mph... Pretty tough to do though...

Steve

[HARPOON-OR-BUST]

I would also recommend going to Mercury's HSOforum and using their prop selector, works pretty good. They will give you the options you have. The performance is going to be quite noticable with the SS. What another few hundred on several thousand!