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 New Prop = New Speeds 
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Location: D'town, LA
Post New Prop = New Speeds
Well...nothing all that noteworthy. I have read on here several times about Prodrive stock props varying from one prop to the next. I think I just experienced that difference.

Original stock prop turned ~3950'ish RPM's and was rolling steady 26 mph, bumping 27 in deep water.

Just picked up another (used) stock tulip prop from riverrunner342 and took it out for the first time today. I would say loading was comparable with my first speed trial. I was minus one battery and the trolling motor today...but did have my "lay-yak" in the boat and a full 16 gallons of fuel. I ran steady high 27's and the occasional low 28 mph. GPS said I hit a max of 29 once...I'm going to blame the GPS for that one. :lol: RPM wise, I was turning about 4050'ish.

The Hopkins Cleaver prop still gives me a much better hole shot than either of the two Tulips....without a load. The Cleaver doesn't do loads...yet.



Sun Dec 08, 2013 12:14 am
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Post Re: New Prop = New Speeds
You look cold! lol

Nice speeds! especially for a CC.


Mon Dec 09, 2013 7:52 pm
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Post Re: New Prop = New Speeds
40 degrees and spitting mist....it was a little nipply out there, Saturday. :lol:

But still 20 degrees warmer than my house up in North MS on Saturday!!


Mon Dec 09, 2013 8:10 pm
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Post Re: New Prop = New Speeds
Your motor is starting to break in. Things will move better now.

And the cold weather helps alot with RPM's.

That might be the difference you are experiencing.

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Mon Dec 09, 2013 9:32 pm
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Post Re: New Prop = New Speeds
I questioned in my mind about the cold weather. I know back when I used to do all that crazy endurance stuff, I always seemed to bike/run faster/further in the cold. Guy told me once that it was because you are taking in more O2 in colder weather. Not quite sure I bought into that as much as I did the fact that body core temps stayed cooler...didn't overheat so to speak.

So, what would make the engine perform better in colder temps?


Mon Dec 09, 2013 9:38 pm
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Post Re: New Prop = New Speeds
Cold air is more dense so really you can pack more air into the cylinders.

my twin thumbs and today's cellular technology

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Mon Dec 09, 2013 10:16 pm
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Post Re: New Prop = New Speeds
That's pretty much how the guy I used to do triathlons with explained it. Gave the cold=contraction vs. hot=expansion thing. Said you could take in more molecules of O2 in colder weather because they became smaller/more concentrated in the air you breathed.

I always went back to a straight 6 258 I rebuilt for a Jeep I had....it had the air preheat duct that preheated air going into the carb. It had a temperature control valve in the intake that regulated the fresh air with the heat to increase (or regulate) the temperature of the air going into the engine. I was told this was done to make the engine burn more efficient/less emissions. It seemed to contradict the cold air=better thought.


Mon Dec 09, 2013 10:28 pm
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