more speed AGAIN, blow out?

glen76 · 01-03-2010, 01:42 AM

getting 46knots with 500kg of fuel onboard, on 200 opti at 5100rpm with 21 laser2 prop, above 1.5 on smartcraft trim the prop does what i think is blow out, it surges by 100rpm at WOT and makes a deeper noise and looses a knot or two.... quite a bit of slip on the prop with any sort of hard turn too. Desperatly want 50knots. whats max rpm on 200 opti and how close can i run it safely.

I was thinking of a similar or slightly smaller 4 blade maybe??

Hydrostream · 01-03-2010, 02:11 AM

Smaller blade will blow out easier in turns.

Are you using much trim when it blows out? try something with more bow lift if you are, a mirage maybe. Or some setback

glen76 · 01-03-2010, 09:45 AM

Quote:

Originally Posted by Hydrostream

Smaller blade will blow out easier in turns.

Are you using much trim when it blows out? try something with more bow lift if you are, a mirage maybe. Or some setback

difficult to say how much trim, its about 1/3 of the engines range. mercury details says a laser is for 15-18ft boats, is there some reason it cant cope with the added weight as boats not a lightweight for its size.