Pursuit 32 4074 1400kv set up questions..

[jamie6662]

Hello all.Just joined the site ,im located in NSW Australia .After reading up on Pursuit threads for a few weeks and going round and round in circles on how to set up .Thught id see if my thinking is on the right track here goes..
Have upgraded flex from OSE 4.75mm, Turnigy t180 esc,extra water pick up,will carbon fibre the inner hull for strength.
I will be running in flat water sometimes but also in choppier water in the sea (bay area) im thinking of going leopard 4074 1400kv on 6s which should give me reasonable running temps and runtime with reliability.My thinking was i wont be running flat out all the time in choppy water so the torque may help and will this give me a better runtime compared to say 4074 2000kv on 4s on the same MAH batteries?
Next onto batteries,i see to get the correct CG i may need 2 packs one at each side of motor..
i thought maybe 30c batteries would be ok due to lower amp draw but not sure if i should have 2x6s 5000mah packs in parrallel or 2 x3s 2500mah packs in series.
Also wondering about max battery weight the pursuit can carry ?i know more weight will affect speed but may help in rougher water?
As far a s props go im not sure yet runtime vs speed,heat etc?
Hope this makes sense i have read lots of set ups in different ways but would like to get a bit more runtime than 4 mins out in the sea possibly not on full throttle all the time .
Reading this back think i have confused myself even more now

[pugman2]

im going for the same thing you are got a pursuit hull handles great . did esc mods going to run extra pick up to try to keep things cool for longer runs. im thinking about trying 1800kv. been trying to decide on motor an s count 5s or 6s most likely gonna be 5s

[jamie6662]

I was thinking running the 4074 1400 would give me lower amp draw and be able to turn a decent size prop on 6s without running too hot.Looked at 5s 1800kv to.I want nice bursts of speed but longish run times in the sea thinking around 7 mins not on full throttle should be achievable?

[78MaicoRider]

"4074 1400kv on 6s which should give me reasonable running temps and runtime with reliability.My thinking was i wont be running flat out all the time in choppy water so the torque may help and will this give me a better runtime compared to say 4074 2000kv on 4s on the same MAH batteries?"

6S (22.2V) 5000 mah is 50% more total power than 4S (14.8V) 5000 mah. So if the two motors are the same wattage and are loaded the same say 80% of max, the motor running 6S will run 50% longer theoretically.

"i thought maybe 30c batteries would be ok due to lower amp draw but not sure if i should have 2x6s 5000mah packs in parrallel or 2 x3s 2500mah packs in series."

2x 6S 5000 mah packs in parallel gives you 6S (22.2V) 10000 mah. 2x 3S 2500 mah in series is 6S (22.2V) 2500 mah or 1/4 the total power of the 2 6S 5000 packs in parallel.
Also 2 6S 5000 mah packs is a lot of weight for a 30 inch boat. I hope this helps you with your choices

[jamie6662]

Thanks for the info.Just realised what I wrote with batteries , I meant 2x 6s 2500 in parallel for 5000 total or 2x3s 5000packs in series.So looks like 6s should be what I'm looking for with around 5000mah total .just gotta see what props work with that motor now, maybe m645, m445 or 3 blade from what I've read

[srislash]

Did I read that you will be doing ocean runs?
That is all good, may have a few recommendations for you but you are on right track.

[lenny]

I just use a single Turnigy 4s,5s,6s, 30c to 40c 5000mah pack,
And get 5 minutes of run time at about full throttle running.
But two 4s to 6s pack at 30c 5000mah will give you better run time and handling in the choppy sea,
Also go with a three blade prop because it will help to with handling and torque roll.

Hey Shawn,
Did you get you pursuit back yet ?

[jamie6662]

Just looked at your vids on youtube Lenny,your Pursuit is running nice made me possibly have a rethink about 1400kv and maybe going a bit higher you think running 6s on 1800kv is ok long term ? how are the temps swinging the 3 bade prop after 5 mins? what would the difference in performance/speed be say between 3 blade and 2 blade of same size?
One other question did you manage to get the CG around 10`` from the transom with a single pack? i was thinking of mounting esc somewhere behind the motor towards back to offset battery further forward to save running 2 packs down the sides
I will be doing runs in lake but also in a fairly protected bay area in the ocean should be fun for bashing around

[lenny]

My temps where good on 4s and got lower on 5s and 6s,
I am not really sure about the long term on 6s yet.
Because I need to do little more testing in the summer heat and waters I think,
As for two and three blade x447 props.
I think the performance and speeds are very close,
But the three blade makes the boat run a lot smoother with less torque roll to.
My esc is on the port side of the motor to also help with torque roll and cg,
And yes cg is good at 10" setup like this.

Hears a little more info.
http://forums.offshoreelectrics.com/...-6s1p-55-8-mph

And Shawn build thread.
http://forums.offshoreelectrics.com/...ket-quot-build

[srislash]

Hey Shawn,
Did you get you pursuit back yet ?

I got the boat back Lenny. Hatch is under 10ft though and we have a new cold front in.

To the OP, I ran both 5s and 6s on a pair of 1820kv 4082 TPower's and they were fine.

[jamie6662]

Looked at Lenny and shawns build great attention to detail definately given me some ideas hopefully i will get mine running somwhere near those.Just trying to get my head people running higher kv 4s lipo or lower kv 6s lipo and getting around the same top speeds. I have seen on youtube Joker RC pursuit with a 4074 2000kv (29600rpm) 4s 447/3 prop hitting 96kph .... so if i use a 4074 1400kv on 6s (31080rpm ) with same 447/3 prop i should be able to get around the same speed? but the 2000kv is rated at 120amp and the 1400kv is rated at 80amp does that mean the 1400kv will run cooler and use less amps resulting in more runtime?And would the 1400kv have better torque to accelerate quicker ?

[lenny]

What you see on youtube is sometimes is just BS and a bad setup waiting to smoke,
That is why I like to see nice long video's posted of of anything running.
So we can see what is going on and how it is riding with temps readings on everything and gps reading help to.
I would think that going with a little higher kv than 1400kv will give better choices for volts to run in it,
Like I can with the 1800kv setup.
With the lower kv it will have more power and torque to spin a bigger prop with less amp draw,
But the hull may not handle what the motor can handle and turn as for bigger props.
If you do not over prop the lower kv setup than you should end up with lower temps and a little longer run time to.