Help $250 bet

[Johnc]

Ok guys,
I have a $250 bet for this summer that my Zonda 41" can beat his hydro (gas: not nitro) in basically a couple of saw runs.
So, here's what I have: twins of course: 120a esc's, sss 2075kv motors.
Last fall (before the water got hard) I ran it with x442 b/s and it ran great (12s (6s each side, 5200Mah 50c)) then it slowed down tremendously, so upon inspection one of the wires from the esc to the motor just fell out of the esc (no heat, no burns, no smoke) Not sure what happened there.
But anyways, suggestion's to beat this guy? He says he gets 85mph (yea, good luck with that, he never had a gps in it)
Don't want to go over board on $ but willing to go as far as I need within reason too just to beat him (pride thing I guess)

Oh: in setting this up I would like to be able to just do fun runs (not just saw runs) around the pond with max amount of run times as well.

John

PS: did some searching on this and there is so many (who's to believe the internet though) on this. Need all of your expert advice data.

[fweasel]

6S on 2075 motors in a 41" twin cat can get you into the high 80's, but you'll need better ESC's, 180A minimum, and I would run external cap banks. Those speeds mean harder crashes. Look into reinforcing the hull seams from the inside at a minimum and making sure your pool noodle game is strong.

[Johnc]

thanks,
plan on upgrading to the 180's and yes did the reinforcing as stated. Instead of pool noodles I use "pipe insulation" basically same stuff (cheaper) but available in different diameter's, and has a slut (sorry slit) down it with adhesive that can be used if needed.

[Bp9145]

6S on 2075 motors in a 41" twin cat can get you into the high 80's, but you'll need better ESC's, 180A minimum, and I would run external cap banks. Those speeds mean harder crashes. Look into reinforcing the hull seams from the inside at a minimum and making sure your pool noodle game is strong.

Thinking the same thing with Ryan with at least 180A escs and reinforcement of the hull. But here's another option that can give you another edge is get in touch w/ Chris Hoffmann, aka Dasboata, he might have a better option for you besides those X442s. . . if you really want to win that $250. But, ask fweasel I think he had a Zonda at one time or might still have it and if he did he'll know more about props for it. . .Good luck and I hope you beat your friend.

[Fluid]

X442s may not get the OP where he wants to go, not enough thrust cone and not enough pitch. He doesn’t tell us the motors he has, I assume 3675 which is a little small. It would also be helpful if he told us the speed he got with his setup. I assume well under 85 mph.....

If he limits his running to two (2) passes he can get away with a higher amp draw than what is normally safe. It isn’t amp draw which hurts, it’s the heat buildup. Serious SAW setups only get two passes....


.

[Johnc]

Hello Mr. fluid,
In your response, they are the sss3675, and no I do not have a gps speed (lovely son stepped on it and broke it, what the hell is that, waiting for him to replace it out of his pocket)
2 passes and maybe 3 or 4 with cool down is ok with me. Just want to beat his a** lol

John

[Revolt Flash]

Do what Ryan said with 180 esc's or better and get some props from Chris also. Our Zonda went 72 with just a CNC pair of 3 blade 48's with same motors and 120 esc's on Garmin GPS

[Nevs]

can see on youtube that a lot of records are set with ABC 1915 and 1815. A 3674/2075 kv/6s is probably better of with a ABC 1715.

https://www.modellbaucenterlorenz.de/de/propeller.html?ajaxcatalog=true&manufacturer=6&p=2

The nominel teoretic speed would be:
2075 x 22,2 = 46065 rpm x 43 x 1,5 =297..... = 2,97 x 60 = 178 kmh/111,4 MPH
With 80% effectivety you would have a speed of 89 mph, (some cats can get in the 90-95% range).
The problem with the 3674 motors could be that they drop a lot of rpm under load.

[dasboata]

Ok guys,
I have a $250 bet for this summer that my Zonda 41" can beat his hydro (gas: not nitro) in basically a couple of saw runs.
So, here's what I have: twins of course: 120a esc's, sss 2075kv motors.
Last fall (before the water got hard) I ran it with x442 b/s and it ran great (12s (6s each side, 5200Mah 50c)) then it slowed down tremendously, so upon inspection one of the wires from the esc to the motor just fell out of the esc (no heat, no burns, no smoke) Not sure what happened there.
But anyways, suggestion's to beat this guy? He says he gets 85mph (yea, good luck with that, he never had a gps in it)
Don't want to go over board on $ but willing to go as far as I need within reason too just to beat him (pride thing I guess)

Oh: in setting this up I would like to be able to just do fun runs (not just saw runs) around the pond with max amount of run times as well.

John

PS: did some searching on this and there is so many (who's to believe the internet though) on this. Need all of your expert advice data.

sure put a set of my props on it !!!!

[complacent_one]

Also, keep in mind, depending on the type of pipe insulation (much of it is neoprene) it can be as much as triple the weight as the same diameter pool noodle.

[Johnc]

Understand about the pipe insulation, what we have here weighs like nothing, held it under water for about an hour and really never absorbed any water either.
Ordered my props from Chris (dashbota) today (went with ABC17165's) Want to beat this guy's butt, he's so into himself

[Bp9145]

Understand about the pipe insulation, what we have here weighs like nothing, held it under water for about an hour and really never absorbed any water either.
Ordered my props from Chris (dashbota) today (went with ABC17165's) Want to beat this guy's butt, he's so into himself

Well, when you win the $250 you'll have your props and escs and motors almost covered. . .but the bragging rights. .priceless. .

[rol243]

you will need to keep the Zonda on the water without it blowing over. what type of hydro does you mate have. sport or rigger, be carefull Johnc, he might take your money. lol

[Speed3]

Octura x447 counter rotating, some negative trim on the drives, swordfish x220 or x300. Hope you are using upgraded shafts.

And strong batteries like turnigy heavy duty 5000 60c 6s. Make sure every connector is properly soldered.

I would not use any 42mm prop not efficient enough. I like the octura over the ABC 17 45 rake because the ABC creates a lot of bow light and increase your risk of blowing over. The octura don't create anywhere near the bow lift making staying on the water easier.

By the way I have seen these kind of races gas versus electric. Where electric was just as fast or faster than twin engine gas boats.

And a twin engine gas boat does be a lot faster than a single engine gas boat.

[fweasel]

For clarification, the Octura props create lift at the back of the boat, forcing the bow down. The ABC 17*45's do not create the lift at the rear, and require more negative trim than an Octura prop on an identical setup. This isn't a problem, in my eyes. Like anything else, you have to tune for a specific set of parts installed on a boat. The ABC props are faster, but create more load, which means more heat and shorter run times, all things equal. Likely not an issue since this particular thread is all about GPS racing.