WOT for 19" vs. 21" Pitch for 5.7L Merc

[neikrk6]

I have a 1996 Conquest Bowrider with a Merc 5.7L 260hp I/O. Last weekend I ran 55 mph (GPS) at 5500 RPM. Is this above the recomended WOT rating for this engine? I would like to upgrade from a 19" x 14 3/4" SS 3 blade prop to a 21" with same diameter. Is this ok or should I look for a larger diameter or 4 blade prop? It makes me a little nervous for a V8 engine to run at that high RPM. Please advise...

 

[Tail_Gunner]

Re: WOT for 19" vs. 21" Pitch for 5.7L Merc

Get some good advise and go see Bond-o and get his opinion on the rpm range for that engine Or Don, differnet people but very sound advice pay attention to them both.

 

[jimmbo]

Re: WOT for 19" vs. 21" Pitch for 5.7L Merc

4800 should be about the max rpm for that engine, 4600 if it is pre vortec

 

[Bondo]

Re: WOT for 19" vs. 21" Pitch for 5.7L Merc

Ayuh,..........

The 21" might get you in there,...... Or possibly a 23"......
But you Do want to shoot for 4600/ 4800rpms as your WOT rpms..........

 

[Silvertip]

Re: WOT for 19" vs. 21" Pitch for 5.7L Merc

Verify the tach before spending bucks on a prop.