alright somebody tell me!!!! i want to know tow things!!

[scorpien boats]

what is better (top speed wise) a three blade prop or two


and what is better (top speed) the os .15 cv-rx or the traxxas 2.5?? the traxxas 2.5 has 50000 max rpm......

[hydromania]

to your prop question,2 blades are pushing props.These are good for speed with no lift.Balance is not as good as the three blade but are popular with any surface drive gear.

Three Blades are good if lift is needed to obtain better speeds,balancing of these are a bit more difficult.On surface drives they can cause cavitation in corners since the pitch per blade is not as much generally becuse it is devided between three instead of two.I believe that I am correct.if not someone will reply promply to that affect.

Also I am sure some one running the same type of set up will let you know what works best for them.

[Ron Olson]

Good! My posting this morning didn't get entered. I wasn't too awake when I typed it. PLEASE proofread your posting before hitting enter. I do this all the time, you ought to see how bad mine look before posting! I'm a great speller but can't type worth a hoot.
OK, 2 and 3 blade props both have the same diameter and pitch, i.e., an Octura X440 and X440/3 are the same except for the extra blade.
A Traxxas turning 50,000 RPM? Yeah, right, suuuuuuuuuuuuuuuure it does! The best .12-.18 motors are only cranking out an advertised 38-43,000 RPM and that is advertised. Note that RCCA has stopped putting in RPM and HP numbers in their new Buyers Guide, not too many Manufacturers can back up their outrageous claims!
Out of those two (not tow :) ), I'd go with the O.S..

[scorpien boats]

yeah i know i was at school when i posted this thread and i realized it misspelled two......but it was too late cause the teacher was coming...

yeah i know it does sound a little crazy 50000 so the os would be best??

[Hydro Junkie]

I agree with Ron. The 50K RPM that Traxxas claimed was most likely on the test stand with no load and IDEAL CONDITIONS. I don't even trust O S and K&B claiming 25K on their big .67 inboards. Real world is probably more like 18 to 20K. I'd go with O S on this one. As both are the same size, I'm looking at how dependable the O S line has been in scale hydros. Don't think I've ever seen one break :)

[Chris LaPanse]

I'd go with the Traxxas. In the T-Maxx, it turns 46000 rpm at top speed (friend's T-Maxx's radar tested top speed used to find RPM's) Also, it puts out a dyno tested (RC Nitro) 1.4 hp.

[scorpien boats]

im sure the 2.5 is a pretty good engine but i dont think it will last as long or be able to keep up with the os .15 cvrx, if i were to bet i would have it on os

the only reson i was thinking about the 2.5 is because i could give them my .15pro and the 2.5 would only be half the price.... but now that i called traxxas and asked them if they had the water cooled head in stock, they said they dont and they are not going to get it for a long time......

so that puts out the traxxas.... o and plus slide carbs dont intrest me very much..

[Ron Olson]

.......and they're a pain to set up in a boat. It's doable but a hassle.