*Fast* scale boat

[vvviivvv]

i kinda hijacked another thread and didn't get replied too i was just wondering about using twin feiago 8xl's on 4s in my scale boat its 1.31 meters long and is geared 2:1 or 1:2 ( sounds silly but small cog is on motor and bigger is on the shaft so that means its 1:2?)

the boat has 2x jet units 40 mm Ø impeller,

Length approx. 250mm
Length incl. reversing mechanism approx. 290mm
Width approx. 58mm
Height approx. 70mm

this is the kind of speeds i would like http://www.youtube.com/watch?v=1cClZ4FYc3E it would just be straight line because i wouldn't want to flip the boat... the boat in the video uses Engines: 2 X Robbe Brushless Innrunner 3650 (2100kv)
Baterries: 2 pcs Lippo 4800 mA / 14,8 V

are the feiago 8xl's suitable? the amp draw is suposedly 1/2ed with the gearbox?

anyone have any dobts in this set up ive had this boat for a while on graupner 700 bb turbos on 9.6v and its about 10 - 15mph max

i am also in the process of ordering two Neu 1521/1.5d or 1Y for my hpr115 which i could put in here if 8xl's are no good and run on 4s

but hey whatever just tell me what you think.

[Fluid]

To get higher speeds with the jets you will need higher Kv and adequate torque. The 8XL should have enough torque and based on the video boat's specs they should work well. The gearing is a 2:1 reduction, normal for high-Kv motors or motors which lack torque. Amp draw is based on the load, not the gear ratio - although all else equal the gear box will reduce the amp draw and reduce the output rpm.


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[vvviivvv]

I've been told the max rpm for the jet units is 15,000 does any 1 question this or do you think they will hold up to this?