The Black Pearl P Sport Hydro 2017

[T.S.Davis]

Oh, Boat does not like big prop/lower kv setup.... It will start to porpoise if I hit any rough water. Little prop/high kv and the boat just hops up, flies level, then sets back down.

The last Pearl I built didn't like the big props either. It was happier with the 1515 and a smaller prop. My old heavy whip liked a 447/3. Go figure. This next Pearl that is on the bench will be a tank so all bets are off on the setup. Might go back to the 1950 and try fat props again.

[CraigP]

For me, you’re right at the best part of RC boating... The wondering, the figuring, the building, the anticipation of the first run. Is the weight right, did I hit the turn fin adjust right out of the box! I really enjoy that part!

Got a crazy idea I’m working on. (YeH, even more out-of-the-box than usual, lol!) I’m going to get another Vortex 34, because there’s so much bloody room in there, and set up a dual motor, dual prop setup. Been kicking around a couple of 2860’s with a center rudder and running a full dual motor mixer on it. I know no class for it, but just have to try it out! I want to try spinning the port side prop CW and the starboard side CCW. I’m wondering if it will cancel out most of the prop torque. Would turn the shafts pretty fast 35,000rpm and use small props, like 42-43mm.

[Moonie]

Antonio

The hull that runs 70mph is one of the old 5.7 kits
This build and hull is a lot heaver then the new light weight kits.
It also has some of my own mods built in.

It is a full "P" setup
NEU 1515 - 1Y - 2200KV
Two 4S - 5000's 65-130C
Castle Hydra 240amp
Timing set to 15 Degrees
ABC - 1815 -17 -45

Build thread:
https://forums.offshoreelectrics.com...10-Black-pearl

Pictures
https://forums.offshoreelectrics.com...p?albumid=1364

I have since changed the turn fin, to make the hull more steady and run true without pulling to the right.
Also had to replace my drive tube, due to a dent in it that I did not notice, - lost two shafts at the last race.

Larry

Thanks Larry. I'll have to grad one of them props.

[Moonie]

2310 is pretty hot. Which motor is that? 4070? It could work with a small prop. The 1515 runs warm too at 2200kv.

For me, I prefer a few less kv with more blade in the water but results vary depending on which boat you're running. Some boats don't like a big blade. The Pearls do pretty well on 45mm props. A 45mm on a TP2310 will likely come in hot on the oval. Zip zip playing around it will work fine though.

Your right spot on with tha one T. I try it and the 4050 2310kv is a hot setup on a 45mm.

[Shooter]

I haven’t even tried turning full throttle, just feels like a suicide mission, lol.

Hey Craig, what fin are you running? We usually keep the throttle pegged the whole race, even on the small radius turns on the practice pond. Keeping speed in the turns is a challenge. Best sport boat I've seen is Mike Ball's PT spec boat. It used to literally whip itself around the turns like a rigger with very little speed loss. We are getting closer to that with the recent changes (packaging most of the weight directly on the CG), but it's still a challenge with full P power.

[CraigP]

Hey Pete, I’ve had 3 fins on the boat. First, a UL-1 fin with a side brace. That still deflected badly causing understeer at the apex. I got rid of that and put on a Speedmaster bent fin for a 1/8 scale boat. I cut the fin down to proper size for my 34” boat, it worked very well. It turns very well, just never got the nerve to turn full speed. Note, I run the rudder on the left. Then Oscar Love gave me a curved fin, again made for a 48” boat. Cut it down and it just tagged the right side down too hard. Even turning the fin out CCW didn’t get rid of the problem completely. I went back to the bent fin, shown below. I’ve never hooked or flipped the boat, so I guess I just need to turn it one day and see what happens. Pic below on the current fin...

[CraigP]

I have a course set up that’s pretty close to 1/6 mile. Should I just prop down until I feel secure about full throttle turns, then try working it back up?

[Shooter]

Oh Geesh....I'm sorry....I thought you had one of my boats. What boat is that? Sounds like you've tried quite a few things. I've done the same. Straight fins, angled fins, you name it. I always end up going back to a curved fin, thin as possible.

[CraigP]

I’ve got a DF Vortex34... After reading all of this good advice, it seems that I’m running too much prop! Maybe that’s why it feels too fast running an oval. I’ve got an ABC 1815 coming in, that’s about 43mm. I know I’m turning the prop fast, so propping down seems the right direction. I have an 8s setup that turns the prop at 37,000rpm and the 4s setup is just a touch slower, 36,400rpm. I may end up selling my larger prop collection!

[TRUCKPULL]

Craig

An 1815 prop is 45.7mm NOT 43mm

Larry

[CraigP]

I typed that wrong, it’s a 1715

[RayR]

Richard Templeman recently purchased the Pearl built by Sandy (Catboi) Squiteiri, here is his maiden run.

https://www.facebook.com/100011123701036/videos/544167519297367/

[Shooter]

Thanks for sharing Ray! Is he going to bring it to Michigan this year?

[T.S.Davis]

Hey Pete, if you think about it......the Pearl set the two fastest P sport two lap times in IMPBA. Pretty sweet.

Wait until you see Ty's new one. Hope to have paint on it before the winter meeting.

[Shooter]

Hey Pete, if you think about it......the Pearl set the two fastest P sport two lap times in IMPBA. Pretty sweet.

Wait until you see Ty's new one. Hope to have paint on it before the winter meeting.

Very cool.....and those are the older hulls that set the records, without the better turning features and weight distribution changes! can't wait to see Ty's!!