Setup for Whiplash GV or Backlash

[Brushless55]

I'll give it a try next time I go testing. I reset mine at Voodoo since there were 30mph winds and didn't set it back.

Looking forward to your results....

[oscarel]

Jay, two interesting things to me. One is I went from a propworks 6719/3 blade 554 which has 5.54 inches of pitch to a ABC3016/ 2 blade and 4.8 inches of pitch(but a much bigger diameter) and I still have the equivalent top end speed, 74mph. These are two radically different props to say the least and yet they yielded the same top end? Interesting. I can only surmise that I can unload the motor a bit more, reduce the amps a bit, since I have yet to see the top end decline. I am going try some ABC props 2716/2 blade 4.32 pitch (smaller diameter prop, less pitch), and also I think I got a 2518/2 with 4.5 inches a pitch to try out.

The second thing that I find interesting is I see the heat climbing on my Castle HV ESC yet the amp pull is within the specifications of the ESC? I do know the general rule of thumb is to stay well below the max amp reading, but I do seem to be moving within the range of the esc yet there is a steady heat build up on the esc? The math tells me what you are saying Jay, I "think" I could get my six laps in as I went .88 miles and had only used 50% of my batteries. We will see how these new props work out.

Jim, just an fyi on the PWW props. I book marked this page to assist with reading their numbers.

"The 6719's have a staggered pitch and Bob and I have created numbers for them.
554 is 4.45,4.50 and 4.55 inches of pitch If you look at the second # on each blade it comes to 554 (read it backwards
654 is 4.45, 4.55.4.65
776 is 4.65,4.70and 4.70

[oscarel]

Looking forward to your results....

Soooooo....... Moved strut down to 3/4 and it made a BIG difference!! Thanks a bunch Brushless for the tip! I originally had mine set at 1" which is where Brian suggested. My spikes are down 40-50 amps and averages look more in line as to where you are Jim. But look at the temps, gotta love MGM's! No speed readings, I need to get a Geko.

strut down to 3-4.jpg

[electric]

Soooooo....... Moved strut down to 3/4 and it made a BIG difference!! Thanks a bunch Brushless for the tip! I originally had mine set at 1" which is where Brian suggested. My spikes are down 40-50 amps and averages look more in line as to where you are Jim. But look at the temps, gotta love MGM's! No speed readings, I need to get a Geko.

[ATTACH=CONFIG]112440[/ATTACH]

Seriously? Am I reading that right? It shows your temps at about 85 degrees F? If that is true, that is crazy good. Where is this controller you are using?

[oscarel]

Seriously? Am I reading that right? It shows your temps at about 85 degrees F? If that is true, that is crazy good. Where is this controller you are using?

Yep, that's true numbers. Last recording I had at Voodoo was just a little warmer at 97. Now, the esc's aren't cheap.

http://www.mgm-controllers.com/race-boats/speed-controllers-escs-1/tmm-25063-3-for-race-boats-x2-series.html

[Brushless55]

Awesome !

[electric]

Yep, that's true numbers. Last recording I had at Voodoo was just a little warmer at 97. Now, the esc's aren't cheap.
http://www.mgm-controllers.com/race-...x2-series.html

Wow. Yes, those are expensive. Another example of getting what you pay for though. I mean that esc you are running appears to be just coasting along at that amp range you have and could go days without overheating. Very impressive piece of gear. I will stick with my Castle HV until it gives out, but will definitely be looking at your esc when the time comes. I still have not measured my strut, but I will tell you it is up quite a bit(probably closer to 5/8 or so) because I keep pushing it up to get more AOA and "air out" the hull a bit. So far it is handling well and showing no signs of taking flight. You are right that the amp range is looking about the same for both boats at this time. It would be hard for it to given all the weight in batteries we have in there. I am going out to tomorrow to do some more testing with a new prop and will let you know how it goes Oscar.

[oscarel]

Jim, sorry you didn't make the race. I ended up taking 3rd! It was a windy day, I started off with the 7016/2 375 and strut at 3/4 and had a hard time keeping off the 3rd place boat. Second heat ended up blowing over, so I moved the strut back to 7/8 and put on 6719/3 554. 3rd heat lost radio and all the boats in the heat ended up DNF within 2nd lap!! 4th heat was a 2 boat race and I ended up taking 1st the last 1/4 of the track. Shootout I got a really good start and led the whole race. When I got home and checked lipos, I put back in 4200ma and that heat took about 70 secs not including mill of course. ESC hit 140 degrees towards end of run. Here's the graph, I parked at launch pad at end of race so this was for 6 complete laps.

1st heat http://youtu.be/gLX0tUvfMRw

houston shootout round.jpg

[electric]

I am switching my Backlash over to 10s as the Castle 2028 seems to work for me better in my mono(10s), so why not this hydro(lower amps, less heat).

I bought two 6s and two 4s batteries. The problem is the wiring. No matter how I look at it, I am going to end up with about 12" of wire from the battery to the esc. for at least one wire on each side of the boat(pos/neg). This will be the longest run I have ever done. I do have castle capacitors installed right before the ESC. Think it will work?

My only other option is to buy four 5s batteries which will probably have height issues in the front of the boat.

[electric]

Nevermind, thought about it this morning and I can build my y adapters to balance out the length enough from the front to the back. Still might also check to see if I can get fit some slightly smaller 5s batteries in there.

[oscarel]

Jim, what mah lipos did you get?

[electric]

3700mah. So, I will have 7400mah in a 10s2p set up. Using two 4s batts, and two 6s batts. The 4s batts are in the front, 6s behind the motor.

[Brushless55]

Looking forward to your runs on 10s

[electric]

Looking forward to your runs on 10s

Just about have it all together, going to finish it up this weekend and then take it out for test runs, because in two weeks it has to ready to race.

[Brushless55]

Just about have it all together, going to finish it up this weekend and then take it out for test runs, because in two weeks it has to ready to race.

Awesome man!
I am packing up right now for this weekends finals in D20