Joe,
Seriously? <_< Did you not read my post at all? Your shaft is going to wind-up to basically the same point every time it hits the water. With the very same testing you would use to find needle settings, the sweet spot will be found for a given shaft. Once you find it, it will always be there. Even if you change shafts, as long as you stick with the same MFR, it will be very close. I think the only gains to be found are going to be at unloaded, WOT, so varying wind-up due to changing loads will be almost negligable.
A quote from Marty Davis in the above posted linked thread:
An example of this indexing that I have stated for MANY years is a true story:
I had a Beardslee prop that was a cut down 2.8 Octura. (Back then I was doing some SAW stuff). It had rounded tips and was cut down a bunch. I used it on my 40 SAW boat (20 Crapshooter with 45 K&B on mini-pipe). I would run 80-85 mph in 1979. I let Fred McBroom run the prop one day and he ran his boat up on a big boat launch ramp. Bent the prop up. His brother, Hilton, a terrific mechanic and builder said he could bend it back and make it perfect. He did, only thing one blade was substantially different in pitch. I ran the prop and it worked just OK. Put it back in my box and one day I ran it again, and it was awesome. Ran 89.9 mph. Couldn't figure out what had just happened. Started thinking about it and running it again and again. It ran different sometimes at 80 and sometimes at 89. Decided one day that nothing had changed and MAYBE I should put it on the drive dog one way and test it and then reverse it 180 degrees. THAT WAS IT. From that day on I started working with indexing props. True story and one that amazed me in its simplicity and result.
This sure sounds like a measurable result to me.
Personally, I index my own props. Not really for any the performance gain (yet), but for repeatability. I believe it DOES have an impact, and since I haven't had a chance to do the testing, I remove the variable from my set-up by always indexing the prop to the same point everytime I assemble for testing/racing.
Rodney,
I was just turned onto this, so I haven't had time to explore it at all, but.......
Take a head button and thread a new glow plug into it. Mark the head buttom to indicate where the element is welded to the bottom of the plug. Now repeat with another glow plug. And another. And another. As I am told (by what I consider to be a very reliable source), the element will orient to basically the same point with every plug. Now with this in mind, consider the effect of the pipe on the plug. When everything is just right: Needle, pipe length, etc., the plug element will be pulled out of the body of the plug after a good hard run. I've seen mine pull all the way out and sideways toward the edge of the bowl. Wouldn't it make sense to orient the plug so that the element bent the way you want it to? As I was told, if you orient the element weld toward the exhaust port, you will get better results. I can't remember if it was better performance, easier needle, plug longevity or what, but in any case, at least IMHO, it is always better to eliminate any variable that can be eliminated.
Jeff,
That's right.
Keep others from exploring something that might make them harder for you to catch.
Thanks. Brad.
Titan Racing Components
BlackJack Hydros
