Hydro Prop

[ztarum]

Has anyone tried 17, 19, or 21 series props on sport scale hydros? I have a BBY volcanic Splash (1/16 scale) with an OS .15 and have tried x435 and y535. They run pretty good, but I think I could get more. I just can afford to order more than a couple new props to try so I hoped some of you could narrow it down for me.

[Eric Perez]

The ski on the splash will take care of all the lift this allows you to run X-series type props.

I ran Prather S215 and S220 with a Traxxas .15 Turbo and the boat loved them. Actually at those speeds the boat wanted to "FLY" off the water maybe a lifting prop and wings would have helped...

[ztarum]

I don't know anything about prather's numbering system. What is the diameter and pitch to diameter ration? Or what would be a comparable Octura?

[Eric Perez]

Prop # Diameter Pitch
215 1.60" 2.5"
220 1.72" 2.6"
225 1.84" 2.8"
230 1.90" 3.0"
235 2.00" 3.2"
240 2.12" 3.3"
245 2.25" 3.5"
250 2.30" 3.6"
255 2.40" 3.8"
260 2.52" 3.9"
265 2.61" 4.0"
270 2.74" 4.2

[ztarum]

Wow, the 215 and 220 are pretty big. The 215 converts to about 40 mm which is a lot bigger than the 35 mm I've been running, but the pitch is pretty low. Looks like around 1.5 pitch to diameter ratio. I tried a 2135 the other day which had good speed but cavitated horribly and bounced really bad even in the straights. Way too much lift. I'm trying a 1732 and 1735 next.

[Eric Perez]

I also tried the 1732 and 1735 props. A lot of roostertail, but performance was not better than the Y535. Still the best speed and control was with the prather props.

I made some modifications to my BBY BS check them out by going to my website:

http://www.nitrotouring.com (follow the link for RC boat site in the main splash page) ... or just click on the BBY BS logo you can't miss it.

Hope this helps