Mods to my SV

[Fruity]

Here's a couple of pics of my SV27, Still standard motor, upgraded speedie and custom cooling plate, temps stay nice, had a play with a few prop's on the weekend, got 62.4km/h (38.7mp/h)out of it with the X642 in very stable trim, felt like it could even handle a little bit more prop.

I am also trying to dream up some graphics, something with the Aussie flag, if it comes outok, I will post a couple of pics.

I would like to upgrade the motor eventually, but I don't know what to as yet, but I am enjoying this boat.

I also visited the local club on the weekend and found a few FE guys, I am keen to get the SV down and run it around with them, the Club is the Racing Model Boat Club of Victoria - in Australia. If any of the crew I spoke to is on this forum, please say g'day, It was good to meet and chat with you.

Thanks....Tim.

[scoota]

Very neat set up :thumbup1..As for a motor up grade a cheap option is a feigio 8xl
with x445 or x645 will give you 45-48 mph & i have gps 52.4 mph with a prather s230 which is a 49mm prop would not go any bigger than that .. or if you have cash to splash Neu motors are the go for power out put .. andrew at fastelectrics.com.au is very helpful with set ups...

What part of Victoria are you from Tim ?, im always looking for new guys to run with, im in Altona ,melbourne.... jason

[Fruity]

SV

Jason,
I'm in Upper Beaconsfield, other side of the city. I was wondering about the 8XL, it seems a popular choice for an upgrade. The neu's are too pricey.


Cheers...Tim.

[785boats]

Hi Tim.
I Think the first mod should be to move those batteries back a long way.
If I'm not mistaken the hull must be running very wet, robbing you of speed & placing a lot of load on the motor ESC & batteries. I wouldn't put a bigger prop on it in that trim.
Just an observation.
Paul.

[Fruity]

Centre of Gravity

Paul,
It probably looks worse than it is, the batteries ar quite light, my COG is at about 8 1/2 inches from the transom, I have the trim tabs set a wisker low at the moment to keep the nose down, I can get a couple of extra mph out of it just by trimming it out a little, but I am trying to get a set up that can handle other boat wakes etc at a reasonable speed.

Cheers...Tim.

[Fruity]

Paul,
in the attached pic I moved the lipo's back to give a 7 1/2 in COG from the transom. The SV will run very light like this, I will test run tommorow, I raised the tabs a tiny bit as well, we'll see what the GPS says. Last week 62.4kph trimmed in.

[785boats]

Hi Tim.
I guess it was a bit presumptuous of me, but it just looked a bit nose heavy.
As far as an upgrade motor. an Ammo 2300 is good on the original ESC with an X637 or X640.
An 8XL would be a good motor but you would probably need to upgrade the ESC.
Cheers.
Paul.

[scoota]

hi guys , ive been running an etti 150 amp speedie with the 8xl & 49mm prop with no problems , the only thing i dont like about it is the programing thats why for 50 bucks more i upgraded to n 120 Hydra easy to program with the USB link !! with the Aussie dollar the way it is i found the 120 Hydra cheeper to buy in australia from Fast/Electrics.com for $270 or the Etti from RCBOAT BITZ for $220 . tim what speedie are you running how many AMPs ?

[Fruity]

Jason,
I am running an esc meant for a Heli, 100 amp, I made my own cooling plate for it, worked well.

http://www.modelflight.com.au/dualsky/dualsky_esc_xc10018ba.htm

It may be right on the edge as far as amps go with the 8XL, I purchased it from a Heli Forum, a guy purchased it but hadn't used it yet, then I added the bec from the local hobby shop. It came up quite well.

At the moment I have X642 on it, I am interested to see if the standard motor would run ok with a X645 or X646, I might order them and see.

[scoota]

tim ,

I ran a CF45 prop with the standard SV set up and never cooked the 45 amp speedie, i think u should be right with a 100amp speedie & a X645 to start with , run your boat for a few mins bring it back in & check your motor , esc & battery temps if everything cool keep running that prop..

[scoota]

And you will find the best you will do with SV motor & prop testing is 2-3 mph more than your already doing as i did a few years ago when i first got my SV .. i think the sv motors are poorly built ,thats just my thoughts . my boat ran better when i swapped my Black jack motor & esc into it & that motor is only 1500KV ...work that out ? but i have found the 8XL to be the best motor upgrade so far . and yes i think your esc will be on the edge just depends on how well your custom cooling works cause that esc can take 130 amp peaks.... my mate cooked his 100 amp esc with an Ammo 2300 kv motor the other day ....the 8xl will draw 84amps..what it peeks at i cant tell you till i invest in a eagle tree data recorder ....

Jason

[Fluid]

The Feigao motors are no better-built than the SV motors, but they are very different in design. The SV motors BTW have delivered speeds into the high 50s in different hulls. Comparing the potential power of an SV motor to an XL motor is pretty apples and oranges.

The biggest problem with the SV27 and high speeds is - the model is really too small to handle high speeds (over 45/50 mph) and rough water. No matter how much power you put into it, the boat will still be speed-limited if you actually want to drive it rather than launch it into the air every few seconds. Adding large diameter props can upset the boat further - boaters might be better off using smaller diameter props with higher pitch.

Really, this obsession with GPS speeds is pretty ridiculous, and it leads to outright BS being posted - some modelers read about the speeds others post and think that they should be going faster, so to avoid embarassment they 'make up' a bragging speed. The fact is that some models will never be as fast as another seemingly identical boat because of the normal differences in manufacturing and in setup. And it is well known that different water can effect speeds by 2-5 mph or more with the same boat. Battery pack quality becomes a major factor in speed as you increase amp draw - when I read of someone running in the 50s in an SV with the stock motor and $30 packs I have to wonder.....

IMO the "best" mods for a stock SV - if the boater actually wants to run the boat rather than just become a keyboard hero - are these recommendations from Brian Buaas:

- GrimRacer/ABC 42x55 prop
- SV27 specific adjustable trim tabs from www.offshoreelectrics.com
- Port side turn fin
- 6 oz of lead taped in under the motor.

Depending on the components and setup the above will give speeds in the low/mid-40s with good LiPos. Additional voltage or hotter motors may give higher speeds, but the above-set-up boat will lilkely win the race because it will actually finish.....


.

[Darin Jordan]

The Feigao motors are no better-built than the SV motors,

With one caviat... The wire in the SV27 motors is more brittle and doesn't seem to hold solder as well... When really pushing them, they have a tendancy to desolder the contacts unless you take a LOT of time getting the wires prepped and getting the contacts soldered securely...

BUT the SV27 motor is QUITE potent... It has a GOB of torgue and decent RPM for a 4S setup...

[scoota]

well any one who owns a SV knows how bad the handle at speeds over 40 mph , but its been a fun getting it to run 52 mph ( in a straight line only & on glass!!!)& i will say with the 8xl ,120 hydra & good battery packs i wont buy cheep lipos the boat has been bullet proof!!! As for runing big dia props that is only to see what top straight line speeds i can achive ...Thats why im in the middle of building a 38 inch cat with a 1521 1.5y Neu on 10cells something that will handle a bit of chop & other boats wakes & 60plus mph. This is a video of the set up im basing my build on

http://www.youtube.com/watch?v=yMs0ghSzBIc

Lets face it the poor finsh of the sv hull has a lot to be desired just run a straight edge along the bottom of the hull & all the edges need sharpening!!!! they need a lot of work to get them right ..that also has a lot to do with the handling....

[Fruity]

Fluid,
your points on the mods are valid, I have all of these on my SV already. Also on the 8XL, the reason I have not purchased one already is the fact that it is a 2 pole motor, vs the SV's 6 pole (I think). If the 8XL was 4 or 6 and the size of the XL then I think it would be a powerhouse.

On the subject of GPS readings, it is one of the best ways to see if your set up changes are making a positive differnce - imediatly, as soon as you return to shore, there's your data.

You must also appreciate that everyone is in this hobby for different reasons and enjoy different challenges. So please give from your experience freely, but keep it positive, comments like "keyboard Heroes" don't help anyone, and may take the shine off the other very valid points you make.

Thanks...Tim.