super vee 27

[NAMBA860]

im going to upgrade my sons boat. we have been running two 6 cell packs 4200mah i was told that i need to go to 2 lipos the one i picked due to price are the 2 cell 2100 mah. is this ok to run in that boats stock configuration?

 

[AlanN]

If you only want a minute run time they would be ok.

You would not be paralleling them so you do not double the mah's.

Most preferable would be something in the 4500mah range. (2) 2S1P packs to make a 4S1P total.

Be careful with lipos. The stock speed controller on an SV does not have a low voltage shut off. If you run the boat until it slows you may damage the cells.

 

[NAMBA860]

If you only want a minute run time they would be ok.
You would not be paralleling them so you do not double the mah's.

Most preferable would be something in the 4500mah range. (2) 2S1P packs to make a 4S1P total.

Be careful with lipos. The stock speed controller on an SV does not have a low voltage shut off. If you run the boat until it slows you may damage the cells.

wouldnt these last longer then the two 6 cell packs i have in thers now?

 

[AlanN]

No. You are decreasing the mah's which is the size of the fuel tank.

 

[NAMBA860]

No. You are decreasing the mah's which is the size of the fuel tank.

so your saying i need 2 / 2 cell lipo packs around the 4200-4400 mah range. is that correct? how long will the boat run with those?

 

[Bill-SOCAL]

I run my SV using two 2S 3700 mAh 20C packs in series. Running a 440/3 I can go for a full mile race plus mill with no issues. I can also run the 4 minute offshore with that prop, no worries.

But large packs would not hurt, because frankly with the smaller packs the boat is too light. I'd recommend at least 4,350 to 4,500 cells. RC Lipos has some on sale for the holiday

http://www.rclipos.com/PolyRC25C.htm

Scroll down to here: Poly RC PQ-4350XP-2S Li-Poly Battery

 

[TRUCKPULL]

You are now running 2 - 4200mah packs in series

Giving you a total of 12 cells (or 4S) at 4200mah total

So to be equal in Lipo you need 2 -2S packs(4200mah) in Series.

As Alan said, with Lipos you never want to run below the 20% of capacity.(damage cells)

I would go with the 4500's or the 5000's

Also you can buy a Low Voltage cutoff, It connects between the ESC and the receiver.

When it sees the voltage down around 12 Volts it will slow you down, but let you drive

it back to the dock.

The Lipos will be faster because they will maintain a higher voltage under load.

Larry

 

[NAMBA860]

my son is only 8 years old im not worried how fast it goes just a good enexpensive set up so he can learn to drive before i turn him loose with his nitro boat.

 

[AlanN]

Just keep the prop on the light side. 440 dia or smaller and he will get some good run time and practice. 3-5 mins depending on setup. With 4500 or higher cells.

Bill, remember just becouse your setup will do 4 mins another strut angle or depth may not. And as you know the trim tab settings can rob you of power and runtime. Don't know how he has his set up.

 

[BB Mods's]

Guys, The SV27 ESC DOES have a lipo LV cutoff.

We have confirmed, and Grim agreed that the ElectriFly SS-45D IS the ESC used in the SV27, The thing to remember is the LV cutoff only works properly if your lipo packs are fully charged at the time you put them into the boat.

This is the ESC thats inside the anodized case.

http://www.electrifly.com/escs/gpmm1841-2.jpg