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4 Blade Prop Question

Posted: Feb 11th, '11, 09:31
by gmelvin
I found a set of Michigan Dyna Quad 17x17's, new for $300 ea. Anybody know if they could be used on a B31 Sedan with Mercruiser MPI 340hp's?

Glenn 76 B31 577695

Posted: Feb 12th, '11, 12:57
by Pete Fallon
Glenn,
I am running 17x19 3 blades on my 1961 31 express with 310 7.4 L with 1:5:1 8 degree down angle hurth trannies, cruise high 20's Wot 41.8@4400 on GPS they work for me. Most of the fly bridge gas boats I surveyed have 17x19 3 blades, the diesel boats are running 20x23 or 20-24 4 blades.
Pete

Posted: Feb 12th, '11, 14:22
by John F.
My ex-69 FBC w/454s and 1.5/1 gears ran 17x15 4-blades with #5 cup--that was as a I remember what I was told they were anyway. Sounds like 17x17 would be fine. $600 set sounds really good.

Posted: Feb 12th, '11, 22:56
by gmelvin
thanks guys,

I talked to the guy selling the props and he measured the bore at 1"to 1.25". I think they would need re-boring to fit the 1 3/8" shaft size, not sure but I think that can be done. They are located about 30 minutes from where I live so it makes sense to go take a look.

Pete, is your express heavier than the sedan versions? I like the 41.8 at 4400! That sounds perfect.

John, it's good to hear from you. I am still working on getting my 31 in the water. The economy slowed me down but I am starting to pull ahead a little now. The boat is still in Deltaville and the engines are here in GA. I am going to tow the boat here next month. I found a good engine guy here at Lake Lanier that is a real 454 expert and we are going to put her on the lake and see a little fresh water for a while. Not too long I hope. I really want to get her back out on the bay. We had a great fall striper run. We never had to run more than 6 or 7 miles out of Herring Creek at Tall Timbers MD. I hope the spring season is as good.

I was realy surprised when you let your 31 go but I am real sure the buyer got a GREAT boat. The pictures you posted a few months ago were great, what a beauty. Think you would get another somewhere down the road?

Thanks again! Glenn