Props 3 blade vs 2 blade

[H&MWill]

I am running an Octura x645 right now and it is the best i have found yet. I like it better than the Prather 220 and the x642. My question is would I get more or less speed out of a 3 blade Grim prop? If you think it would be more which one would you suggest? Thanks guys

[Flying Scotsman]

I am running an Octura x645 right now and it is the best i have found yet. I like it better than the Prather 220 and the x642. My question is would I get more or less speed out of a 3 blade Grim prop? If you think it would be more which one would you suggest? Thanks guys

An X645 is a very aggresive prop, what is your set up? How does your boat run and turn. What are the temps with your present set up?

[H&MWill]

Hi, I am using OSE trim tabs 12 cell 3600's. Octura water pick up. The boat runs very well turns nicely. The Prather was the one that seemed to make it handle the worse. Didnt like the turns at all. With the current setup everything is cool. The motor barely gets warm to the touch. The packs get the hottest like 120. The esc is around 90. Thanks

[Flying Scotsman]

Will, my suggestion would be 4S1P or 3S1P and an X440/3. Look at some other threads as far as props are concerned, bigger is not always the answer for more speed

[H&MWill]

Ok cool thanks. I will have to wait a little while wifey has cut my boat budget since the holidays are coming. LOL

[Ctonez]

I prefer 3 blade. I'm not too sure of the theory behind it, I think more blade in the water at all times is good for this boat's stability...that's the case in my experience.

I ran a detounged 440/3 with Nimhs/Lipos (otherwise stock) and a 437/3 with Lipos & the Ammo.

[H&MWill]

Yeah, I wasnt sure of theory either. The only three blade I ran was the stock one which is horrible since its plastic. I would like to try lipos just been puttin it off since I know nothing at all about them. I am afraid I'll just spend my money and do something to screw em up. The only other person I have been running with is my dad and he runs the same setup.

[Flying Scotsman]

Will, I trust that props such as X645 have been ballanced and sharpenned??

If, not you will have numerous problems.

[H&MWill]

Yes sir all of the props I mentioned are. Oh yeah if I switch to the lipos that you mentioned do I need 2 packs or 1? Also how would I wire them up to the stock ESC?

[Flying Scotsman]

Will. review Jay Turners article in a recent RRC Boat Modelling to answer your questions. As parallel and series make a huge difference, but the end result is voltage and amperage capability

[H&MWill]

Sounds good I'll pick it up 2nite. Thanks again.

[Bill-SOCAL]

GrimRacer 42x55 2-blade. Made a huge difference over the stock prop. Boat gets up on plane faster and runs faster. Batteries and motor warm, but not hot, at end of 7 minute run.

[Avanti]

I have one and I would not recomend the 3 blade grim prop as it is total weak sauce. the 42x55grim works well out of the few I have tried so far.

[Avanti]

I was wrong about the 40x52/3 (41.6mph) with the right batteries (trinity 7.2v 4200mah) this prop is faster than the 42x55 (37.1mph) because it is a bit more stable.

the proboat 1.6x2.5 is a decent prop for a box stock sv, as it will give you the stern lift you need with the batteries in their factory location.

[zero9046]

More food for thought...

Yesterday I was out at the pond and got some "record" numbers (at least for myself).

Wind 20-25 (the pond was fairly protected though)
Slight Chop

SV27 with:
Ammo 2300kv
14.4v cheapo 3300's
BSP Octura 440/3
38.8mph

14.4v IB4200's (that have seen better days)
440/3
45.1mph


Personally, I like the 3 blade octura better. I have ran with the stock prop, Graupner CF 45's and 48's, and the x642, but this has been the best all around prop.

Keep in mind, my top speed runs were downwind, so I'm not sure how much it "helped" my speed. (btw, anyone know if that kind of wind would give my boat 5mph more that without? i was really excited yesterday because I have been dying to break 40 for quiet a while)

Finally got a clear picture of the GPS, so I thought I'd throw that in.

http://i11.photobucket.com/albums/a160/zero9046/DSC00320.jpg