|Fireball V8 in '65 21ft Lyman/prop ch...
Post Number: 1
|Posted on Saturday, September 18, 2004 - 07:40 pm: ||
I have a 1965 21 foot Lyman with a Gray Marine Fireball 327 V8 w/195 hp. At present it has a 13 X 13 prop, and I can get 26 mph at 3100 RPM. What is the hp operating range for this engine? What prop would give me more speed and hopefully more economy? Anyone have experince with this boat/engine combination?
Post Number: 3
|Posted on Thursday, May 28, 2009 - 06:05 pm: ||
I ran a 13"X"13 on my similar Lyman 22' 1963.
The engine should reach 4400 RPM at full throttle if prop is the correct dia. and pitch.
If you cannot reach 4400 RPM you may have too much prop pitch. This would overload the engine. If you can run more than 4400RPM you might need more pitch.
Always select a prop pitch that will allow engine to reach 4400 max RPM. This is where the Fireball V8 makes it's maximum horsepower.
The 13" diameter is pretty much standard on most Lymans of this era & size.
I really like the new four blade OJ brand NiBral props!
They seem to have great acceleration and no vibration!
Hope this helps!
You may be able to use up to a 13"X 16" pitch prop on your boat.
My Fireball V8-C with four barrel carb had 238 HP,