Fine Design Racing

[red6]

You might want to wait and see how it will run setup as 10s2p. There will not be as much voltage sag under load in 2p. Which will give you more speed as well as the run time. On the castle site it recommends running a 2p setup.

T Mono

10S2P

10k-12k mah

2230/1Y

Hydra HV-240

Octura X457

http://www.castlecreations.com/products/neumotors/nm_boat_apps.html

[midwestboat]

For the record, the scale boats he's referring to are most likely not going the speeds you are talking about. But I could be wrong.

I there anybody here going 65+ with electric? What is your runtime? How big of boat? Thanks

Matt

[D. Newland]

I'm in Az now. Left Bloomington in 1988 to head off to college in San Diego.

Ok-good info. You've got a number of runs under your belt, like the handling but don't like the speed.

On 1P cells, 2 minutes runtime is completely normal and expected. That only equates to an amp draw average of 120 amps. Your cells should have drained 4000 mah's during a 2 minute run and got to 130 degrees...? Cell temperature is important to monitor. Keep them no more than 130 degrees +/- after a run and you'll get good life from them.

57 MPH isn't too bad. I know it's not what Chris said, but it's in the ballpark for the power you're thowing at it and you also have to take into consideration the reliability of one's speed guesses.

Going to 10S 2P will get you closer to 4 minutes with the same prop, or allow you to go a bit bigger on the prop (at the expense of runtime).

[midwestboat]

You might want to wait and see how it will run setup as 10s2p. There will not be as much voltage sag under load in 2p. Which will give you more speed as well as the run time. On the castle site it recommends running a 2p setup.

T Mono

10S2P

10k-12k mah

2230/1Y

Hydra HV-240

Octura X457

http://www.castlecreations.com/produ...boat_apps.html

Thanks

[midwestboat]

I'm in Az now. Left Bloomington in 1988 to head off to college in San Diego.

Ok-good info. You've got a number of runs under your belt, like the handling but don't like the speed.

On 1P cells, 2 minutes runtime is completely normal and expected. That only equates to an amp draw average of 120 amps. Your cells should have drained 4000 mah's during a 2 minute run and got to 130 degrees...? Cell temperature is important to monitor. Keep them no more than 130 degrees +/- after a run and you'll get good life from them.

57 MPH isn't too bad. I know it's not what Chris said, but it's in the ballpark for the power you're thowing at it and you also have to take into consideration the reliability of one's speed guesses.

Going to 10S 2P will get you closer to 4 minutes with the same prop, or allow you to go a bit bigger on the prop (at the expense of runtime).

Dumb question, How do you check cell temp? Chris has never told me about this.

[Meniscus]

Temperature gun is one way to do it.

[midwestboat]

Temperature gun is one way to do it.

Another dumb question, I have a temp gun for my Nitro Savage X, Will this be the same? I would think it would but not sure.

[Meniscus]

I would think so. It sends out an infrared light and measures surface temperature correct?

[midwestboat]

I would think so. It sends out an infrared light and measures surface temperature correct?

Correct, just wasn't sure if "battery temp" was measured different.

[egneg]

In this video 2 x 2215 on 10S2P were used to get over 80 mph.

http://www.youtube.com/watch?v=i59znIXWmKw

[midwestboat]

Awesome.

[Eodman]

There are alot of guys running over 65 ... that said I'm 99% sure that with the present battery technology and most of our pockets not being extremely deep we will not see 15 minute runtimes at full tilt boogie!

Just my 1/2 cents but "CATS ARE WHERE IT'S AT" and you got 2 nice ones!

[Fluid]

I there anybody here going 65+ with electric? What is your runtime? How big of boat? Thanks

I race a 41" Stryker cat with 10S and a similar Kv motor. First, you need to run 10S2P both for performance and for ESC reliability. Fine sold a similar build to one of our club members with a 1P setup, and he had poor performance until he added another 1P to the packs.

Second, you don't have enough prop to go 65 mph. I need an x465 minimum to see that speed and have GPS'd mid 60s in an oval race. The x457/3 I ran didn't do better than mid-50s.

Setup is next. Set the CG at 33%. The strut angle looks too extreme but it is tough to tell for sure. Place the model on a flat surface and put the strut from parallel to 2 degrees up at the prop end. I run the bottom of my strut about 3/4" above the sponson bottoms, but you may need more or less depending on the hull.

The ESC is probably fine, although you will pick up some performance by advancing the timing a bit, perhaps between 5 and 10 degrees. Don't try that unless you are running 10S2P however.

I don't know much about total run time, but in a ~2 minute race heat I use up about 4000 mAh. That's full bore plus mill lap for 6 laps. You can figure the run time for 10,000 mAh from that.

There are not a "lot" of guys" running over 65 mph reliably with an oval cat setup. Lots of GPS claims, but when push comes to shove......

.

[Tony]

Dumb question, How do you check cell temp? Chris has never told me about this.

You can get this little gadget to check the cell temp.

https://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=8297

[midwestboat]

I race a 41" Stryker cat with 10S and a similar Kv motor. First, you need to run 10S2P both for performance and for ESC reliability. Fine sold a similar build to one of our club members with a 1P setup, and he had poor performance until he added another 1P to the packs.

Second, you don't have enough prop to go 65 mph. I need an x465 minimum to see that speed and have GPS'd mid 60s in an oval race. The x457/3 I ran didn't do better than mid-50s.

Setup is next. Set the CG at 33%. The strut angle looks too extreme but it is tough to tell for sure. Place the model on a flat surface and put the strut from parallel to 2 degrees up at the prop end. I run the bottom of my strut about 3/4" above the sponson bottoms, but you may need more or less depending on the hull.

The ESC is probably fine, although you will pick up some performance by advancing the timing a bit, perhaps between 5 and 10 degrees. Don't try that unless you are running 10S2P however.

I don't know much about total run time, but in a ~2 minute race heat I use up about 4000 mAh. That's full bore plus mill lap for 6 laps. You can figure the run time for 10,000 mAh from that.

There are not a "lot" of guys" running over 65 mph reliably with an oval cat setup. Lots of GPS claims, but when push comes to shove......

.

Thanks for the info, I will work on this and get back with you.