Chris Craft concept 197 bow rider with a cobra 302 5.0.

ohhenry

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Feb 28, 2015
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3
Hello everyone I purchased a 1990 Chris Craft concept 197 Installed a new deck and a freshly rebuilt cobra 302 5.0 with a new 2 barrel carb ,outdrive was also gone thru. last season was my first season taking it out it never failed starts like a new car with no effort at all very happy with build. Right away I noticed that my top out speed was very slow I am not sure about my pitch because I reused the original Prop, I topped out at around 30 knots 26 to 31MPH what size prop and pitch would be recommended and also I am thinking of stepping up to a 4 barrel carb anyone can suggest sizes and ideas?
 
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Bondo

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Apr 17, 2002
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70,464
What propeller do I need to get more speed? My boat tops off at 31 knots.

Ayuh,..... Welcome Aboard,..... At What rpms, at Wot,..??

What's the size/ pitch of the prop on there showin' those numbers,..??

With an average load,..?? 'bout 1/2 tank of fuel,..??

Cleanly trimmed,..??
 

ohhenry

Recruit
Joined
Feb 28, 2015
Messages
3
Thanks for having me, happy to be on! I usually run at about half a tank if I fill its usually slower and it shuts off so I i have to remove fuel line so that it sucks in air then start right up and goes no problem I am going to replace breather hose soon I replace all in fuel lines so far well back to the point the only writing on the Prop is 9898 on one stamp and AF12 on another and this is playing with the trim to maxim hydro
 

steelespike

Supreme Mariner
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Apr 26, 2002
Messages
19,069
We still need your wot rpm with the 31 mph. I'm guessing your gear ratio is 1.66.
 

Tail_Gunner

Admiral
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Jan 13, 2006
Messages
6,237
freshly rebuilt cobra 302 5.0

What year is this cobra engine, does it have gt 40 heads? Or is this a OMC cobra engine aka is it a roller cam and if you could find the gearing on you leg it would really help.
 

Bondo

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Apr 17, 2002
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On average my RPM full throttle is around 3K It is an OMC Cobra 1992

Ayuh,.... On average don't matter,....

Ya Gotta know the Rpms at Wot, average load, trimmed smartly, 1/2 tank of fuel, just gettin' All she's got,...

To decide what yer prop is doin', 'n what to change it too,......

Necessary Numbers,.....
 
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