more motor ?????

[hammertime]

is there much difference between the 12L and 8XL........ if so what will i see in performance..... i know the difference in size and kv but other than that will i see a difference at the prop in my catamaran.... or speed heat etc

[saleens7]

the XL will have more tourque....so you could run a larger prop...

[Fluid]

The XL will also run smoother and cooler. I have ditched all my smaller 2-pole motors and gone with XL sizes exclusively. I was suprised how well the 8XL ran on 8 cells with an x645, but it is very fast on 12/4S with an m440 or x637. Like Saleens said you will be able to spin more prop at the same rpm, which means more acceleration and more speed. The 3-ounce weight difference is so minor - especially with a 12/4S setup - that you'll never notice.


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[hammertime]

will i see a huge difference in speed from an 8xl from my quannum im running now....in the cat..... on 14 cells..... its a 6 pole motor at 1350 kv.... i was also thinkin about running twins in it as well..... winter project or end of summer...... or do you think i should stick with a single..... i think 2 motors and 24 cells wouldnt be much different cuz of the weight.... or am i wrong..... my major issue is lack of room.... its the bandit cat and it is a very shallow hull..... i have seen videos of this boat with twins and it screamed at 124 kph....dont know what that is in mph... but they were also from germany and im guessing they had some redic power in it and money.... im just gettin board with the speed its at right now i want more more more

[Fluid]

Hammer, IIRC the fast Bandit S in Germany ran twin motors/ESCs/drives on 18 cells; 124 kmh = 77 mph. It is neat, but I would stick with a single motor unless you just like the idea of twins.

You will see much higher speeds with the 8XL versus your Quannum - the main reason will be the higher Kv of the 8XL. The 8XL will run okay on 14 cells, but personally I'd stick to 12. You will not need the extra voltage to get high speeds; I know from the experience of a club member's Bandit S that you can get close to 50 mph with the 8XL and 12 cells in oval trim. Set up for SAW you can top 55 with the right setup.


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[hammertime]

thats what im lookin for...... what would be a good prop and esc..... i want to run this as a saw boat

[hammertime]

will my 70a esc be ok or do i need more muscle

[part time]

if u are going for a saw boat get the hydra 120 . 70 amps and 14 cells only gats u 1176 watts max. and the 8xl is rated for 84 amps so u would be able to make 235 more watts or about 1/3hp with room to spare to push the motor.

[hammertime]

ok see i dont know how all that stuff works..... i didnt realize i could get more power like that.... sounds good

[part time]

volts x amps=watts u can run the feigaos up to 50000 rpms. so if we divide that by 2084 we get 23.99. so that means 20 cells or 24v unloaded. 24vx84amps=2016watts so almost twice the power thats not factoring in the rmp drop when u load the motor or pushing the amp rating. these number are at 100% efficiency

[Jeepers]

DEFINATLY use a bigger esc, if you over prop you can kill a 70 amp esc quickly, I found that out the hard way today, I was testing my dads 70 hacker on my 8xl(he said he couldnt get it set up properly) so i stuck it in my hydro and ran 45 second s smoked it, actually burned a hole in my boat I even proped down from what I normaly run! I usually use a cc125 in my hydro. dang now I owe my dad 200 bucks

[Fluid]

Most folks do not realize that if they want a true SAW boat, they cannot run for more than about 30 seconds before bringing the boat in. Actually, most record-holders only make two passes and bring the boat in - or it may thermal on the third pass.

With the 8XL you can make a semi-SAW boat. In other words, you can prop it so that it will hit a relatively high speed but you won't run it for more than 30-60 seconds. Believe me, you do not want a true SAW boat if you are on a budget, because you WILL burn stuff up! Been there, done that, got the magic smoke stink.

You can use your 70 amp controller to carefully work up your speed, but you will probably not be able to top 50 with it. Actually, right now a very good but inexpensive ESC is sold by United Hobbies - the OEMRC Sentilon100A HV 2-12S Speed Controller is in reality a Hacker 99 that was made by the manufacturer in China on a "third shift". Let your conscience be your guide when buying Chinese electronics, but at under $100 this is a good controller. A couple guys in the club have them and they have worked well so far. I would put a small computer fan on the heat sink, but otherwsise they are ready to go.

Prop-wise with the 8XL and 12 good cells, start with an x440 or x442 and get the cat trimmed, then step up to an x640 or x642. Be careful as you test, use a stop watch and time your runs, keeping them under 45 seconds total and checking heat and speed each time. You may find that as you go up in prop size the speed will rise, then fall. Go back to the prop that gave the highest speed and trim the boat. The fastest attitude is with the bow high, running on the last 3-6" of the sponsons - but this risks a blowover. But, that's what SAW-type running is all about - pushing the envelope.

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[hammertime]

well what i do is just fast passes back and forth.... im not going to be acctually running saws..... i dont run an oval..... just fast passes back and forth..... thanks for all the info..... what about running a brass pipe over the heat sink.... thats what i do in my hammer on the proboat esc..... works good.... and i already have a s/b 440/3 perfect for my first try with the 8xl

[part time]

then what u might want to do is get a tranny. then u can do your fast passes or run it normal all with the same boat. just with a quick gear change.

[hammertime]

im not sure i want to mess with gears..... not a bad idea though.....