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wppracing
04-04-2011, 05:24 AM
Here are the results I have gotten when using different batteries with different C ratings. When I test batteries are in the same location and GPS secured in front of motor. Fresh charged batteries are installed each time.
(the proboat prop was straight out of the package)
Test boat - Miss Geico - no adjustments were made to prop height or rudder- just how it was set up new.

7.4v 25c 5300mah lipo battery using stock prop 31.4mph
7.4v 25c 5300mah lipo battery using ProBoat SS prop 30.9mph

7.4v 35c 5800mah lipo battery using stock prop 32.9mph
7.4v 35c 5800mah lipo battery using ProBoat SS prop 31.5
7.4v 35c 5800mah lipo battery using Octura X642 balanced/sharpened 35.9mph

7.4v 40c 5000mah lipo battery using GrimRacer 42/55 casting marks removed
36.6mph
7.4v 40c 5000mah lipo battery using GrimRacer 42/55 balanced/sharpened
37.3mph
7.4v 40c 5000mah lipo battery using Octura X642 balanced/sharpened
38.1mph

PDR447
04-04-2011, 12:04 PM
what brand batteries?

wppracing
04-04-2011, 12:51 PM
7.4v 25c 5300mah - Dynamite Lipo

7.4v 35c 5800mah - KyPOM K6 Series

7.4v 40c 5000mah - FastRcBatteries.com

lectriglide
04-04-2011, 01:04 PM
Interesting. Thanks for the effort and documenting the results. Just curious, were these taken in similiar water conditions?

wppracing
04-04-2011, 01:15 PM
The water conditions were very close for testing. Each battery type was tested the same day. The 40c were tested on Sunday.

I did some more work on the GrimRacer prop and hope to test it again this evening.

wppracing
04-04-2011, 08:16 PM
Got done testing the prop with the 7.4v 40c 5000mah lipo and used the X642 first . There was a strong wind blowing today but still had to try it. The X642 was slower today at 37.3mph compaired to yesterdays 38.1mph. Ran it 4 runs then switched to the GrimRacer I reworked today. The results were very good - 39.1mph compaired to 37.3mph from yesterday.
Going to get some 45c lipos next and try again.

dirty
04-05-2011, 07:31 AM
fastrcbatteries.com has some good batteries.little pricey,but good.I love mine.I now have 5 sets from him.John is a good guy to deal with

wppracing
04-15-2011, 05:28 AM
Finally received some props from a forum member abd tested the GrimRacer 42/55
Set is 4s 7.4v 40c 5000mah best it did was 40.3mph.

Changed the connectors over to 5.5bullets and will test a M445, maybe this weekend.

ron1950
04-15-2011, 08:56 AM
i am thinking u will get more speed out of the m445....but watch temps

Brushless55
04-15-2011, 11:58 AM
yeah, the higher C rating helps the packs maintain higher volts = more power and rpms out of any system :thumbup:

jac4412
04-15-2011, 12:17 PM
Yes the m445 will give you more speed but you should consider throwing in a 120 or 180amp esc... you're going to start seeing some heat. Good move on the connectors.

Brushless55
04-15-2011, 01:48 PM
I hear that stock esc is a beast?

JackBlack26
04-15-2011, 01:53 PM
200A for these setups is where it's at! I highly doubt it draws anywhere near that but its nice to have that much available for the dreaded spikes from then the boat catches a bit of air and the prop unloads, then drops back in to the water.

Brushless55
04-15-2011, 01:58 PM
I've seen guys run this esc on much bigger hulls and pulling some big amps without issues:thumbup1:

wppracing
04-15-2011, 07:12 PM
What would be the BEST esc to run 120 or 180 and what brand ?
I want to get the most out of a 4S set up.