[*chris*]

I have a 16' aluminum startcraft with a 40hp yamaha 2 stroke. I am currently running a 11.25" x 14 prop and run 28mph at WOT according to my GPS. I do not have a tach yet, waiting for a response in another post, but want to buy a new prop since mine is dinged up from the previous owner. If I go to the michigan wheel prop sizer it suggests a 11-1/2 X 13 for aluminum and 10-1/2 X 13 for stainless. The reason I think I need a new prop is this engine came off of a pontoon boat, which I feel would be a much larger load than my 16' aluminum boat.

Won't the suggested props, with their lower pitch, actually provide more low end grunt? Why is the recommendation between stainless and aluminum so different? Is there any advantage to a stainless prop for my boat? The boat runs fine as it is today and seems to have good top end, but I am not sure if I am missing something. Besides verifying WOT with a tach is there any other way to pick the proper prop? Any suggestions here from experience?

[Crownie2]

My advice would be to get the tach installed and then go from there.

Sounds like you are not far off what Michigan suggests...

Bob

[Rancherlee]

Just because its off a pontoon doesn't mean that they had it proped right. a 14" prop seems too high for a 40hp on a pontoom unless it was a small 16' toon'

[*chris*]

Rancherlee:

Agreed, went out this morning and by myself was hitting almost 31mph. Caught a dozen schoolie stripers as well! If this isn't the right prop, it is very close. I am going to have to get a tach before I mess around with the props. I wish some one would answer my question in the Yamaha forum about a possible converter box needed d

Chris