Can a prop give bow lift???

[gnarley]

Hermosa, does Stingray have that info available for the general public to see?

[steve@kps]

Are there any "prop" guys on here?
props, are like engines, there are too many combinations to just say "this is what you need".
There are props w/ certain blade designs and # of blades to get close to a good setup for a customer. Then the fine "tuning" is done to really bring a prop into specs and get the most out of the horsepower from the engine,outdrive,hull type, etc. Forget the old theory, 3 blades are faster than 4 blades, that is just NOT TRUE in all cases!
This is certain to be long thread and hopefully some really good reading for all to enjoy.
an easy way to describe "rake" .
Pitch is the actual angle of the blade from the leading to the trailing edge. Rake is the opposite angle, from the tip to the barrell, being the heighth of the tip in relationship to where the blade attaches to the barrell. (lay your hand flat on the table, then pull up your fingers towards the palm, and twist the hand, that's what rake is.) eek!
[ January 15, 2003, 10:36 AM: Message edited by: steve@kps ]

[rivercrazy]

I've gone to OSO a few times and there seems to be some prop guru's over there from time to time.
www.offshoreonly.com
Maybe we can encourage some of those peeps to come over and post here. It usually pretty quiet in the outdrive section here on hot boat

[Infomaniac]

steve@kps:
Are there any "prop" guys on here?
Yea You

[steve@kps]

LOL, i just don't want to step on any toes. know what i mean. I hate to interfere in others territory. I respect anyone w/ enough balls to get into the prop business, it's very tough, and very expensive.

[spectras only]

[QUOTE]Originally posted by gnarley:
Hermosa, does Stingray have that info available for the general public to see?, Gnarley, I remember the article mentioned by Hermosa. I think it was in HB .I'll try to go through my mags this weekend and will post it if I find it.

[gnarley]

Attila, that would be great if you find it. Stingray made some hulls very similar to mine so I could get some useful info from that. I'm just about to start the winter work, pull the drive & transom adapter off & re-gel from the rub rail down, after I can do some serious prop testing. I might even install a nose cone while its apart to help reduce the drag. The current prop 14 ½ X 28 3 blade Raker produces to much bow lift and porpoises & is a bit slow to plane so I think a 4 blade cleaver would do the trick but I didn't want to waste money on a prop before I do all the work & then spend it again.

[steve@kps]

gnarley,
You have the right idea in switching props. Too much "rake" creates too much bow lift and will seriously effect the holeshot. too much rake will also cause a boat to turn to the left and scare the crap out of ya at higher speeds.
pitch at the correct rpm's to create horsepower is where the speed is at!

[twistedpair]

There was a pretty good thread on this @ HavasuBarney, you might want to check out this link:
web page

[gnarley]

Steve since you are one of the resident experts would you mind if I sent you some questions by email? Or if everyone wants to learn & you answer them here I can do that also, or even a concensus from others who have been-there-&-done that.