The Voracity tuning thread

[kfxguy]

So far this is the fastest that I have run but I only have 6 or 8 props currently. I'm having fun trying different things. What's amazing to me is that the 4S speed with this prop was 21mph slower than 6S.

The reason is on 4s it doesn't have enough nuts to turn that prop efficiently.

[kfxguy]

Sorry guys, I can no longer hold out on keeping this thing bone stock. I feel that it really needs a good set of trim tabs so I'll be putting a set of speed master ones on probably tonight.

[arrover]

Sorry guys, I can no longer hold out on keeping this thing bone stock. I feel that it really needs a good set of trim tabs so I'll be putting a set of speed master ones on probably tonight.

No problem! We just need pictures that's all.

[Darin Jordan]

So far this is the fastest that I have run but I only have 6 or 8 props currently. I'm having fun trying different things. What's amazing to me is that the 4S speed with this prop was 21mph slower than 6S.

The reason is on 4s it doesn't have enough nuts to turn that prop efficiently.

That's not the reason...

The motor has the same "nuts" regardless, but you have lowered the RPM down considerably on 4S.

If we are being honest here, a 1650KV motor is really NOT a 6S motor. That's a 36,630RPM setup, which are RPMs generally reserved for Hydros and sometimes Sport Hydros.

Monos that are setup correctly run in the 25,000 to 30,000 RPM range. A 35,000RPM+ Mono is usually reserved for SAW or 2-Lap Time-Trial stuff...

SOOOO... INORDER for you to run a 36000RPM setup in a 36" boat, you have to prop DOWN to a prop that won't burn up the motor.

On 4S, you can get away with considerably more prop. You shouldn't expect the much smaller prop needed to safely run 6S to work well at all given 4S RPMs (24,420 or so @3.7V/cell).

However, if you know what you are doing, I see no reason why you can't get reasonably close to 6S speeds on 4S, if you know how to choose the right prop.

[arrover]

Thanks Darin. I wasn't upset or put off by the 4S performance. I like to run the same prop on 6s and 4s just to see the difference. This is only my second boat so I'm enjoying learning about how the prop/motor/esc/batteries work together.

[Darin Jordan]

Has anyone put a real data recorder on one of these setups to see what the LOADED RPM is?

I'd be curious to know. I think I may have that data at home somewhere (when I tested these, I put in an ICE200 so I could see what was really going on), but I did almost all my running with the stock prop, so I'd be curious as to what your data is saying.

[kfxguy]

That's not the reason...

The motor has the same "nuts" regardless, but you have lowered the RPM down considerably on 4S.

If we are being honest here, a 1650KV motor is really NOT a 6S motor. That's a 36,630RPM setup, which are RPMs generally reserved for Hydros and sometimes Sport Hydros.

Monos that are setup correctly run in the 25,000 to 30,000 RPM range. A 35,000RPM+ Mono is usually reserved for SAW or 2-Lap Time-Trial stuff...

SOOOO... INORDER for you to run a 36000RPM setup in a 36" boat, you have to prop DOWN to a prop that won't burn up the motor.

On 4S, you can get away with considerably more prop. You shouldn't expect the much smaller prop needed to safely run 6S to work well at all given 4S RPMs (24,420 or so @3.7V/cell).

However, if you know what you are doing, I see no reason why you can't get reasonably close to 6S speeds on 4S, if you know how to choose the right prop.

I'm going to apologize ahead of time for being blunt, but it is what it is. First off, not any one person knows everything, including you. Secondly, I'll stand by what I said and I have proof. How you say? Well with a 1915 on 4s it runs around 34-35 mph. Went 58 on 6s. Then on 4s with less prop it went 39. Same less prop it went 52. Maybe I don't know what I'm talking about either but it seems to me that with an aggressive prop on 4s the motor has a harder time turning it but use 6s and it has the power to turn it. Prop down on 4s and it goes faster but the same prop goes slower on 6s. I also learned this on my 91mph mono.

Sorry but 35-36k rpm is not "saw" rpm anymore. Maybe 10 or even 5 years ago when motors weren't built as well. But today's quality is much better. I've yet to have a boat motor failure due to high rpm. I'm really tired of people thinking this way. It gets old. No, it's gotten old. I suggest you get with the times. :)


Guys, 6s with 1650kv is perfectly fine ALL DAY LONG. don't be fooled.

[kfxguy]

Has anyone put a real data recorder on one of these setups to see what the LOADED RPM is?

I'd be curious to know. I think I may have that data at home somewhere (when I tested these, I put in an ICE200 so I could see what was really going on), but I did almost all my running with the stock prop, so I'd be curious as to what your data is saying.

I have a data logging mgm Esc in mine. Haven't pulled the logs yet. Pull them tonight. They won't be an accurate representation however. The boat was ran in some nasty seaweed water and only had a top speed of 44mph on 6s.

[Darin Jordan]

I suggest you get with the times. :).

Yeah... OK... I'll keep that in mind.


I think I should just stop testing/designing/developing and racing boats because I'm a little too behind the times.

Not sure how my 1500KV powered IM31 can outrun a 2030 powered Revolt... maybe I just imagined that.

Newsflash... We were running Neu Motors 10-Years ago.... They were MORE powerful and MORE robust back then, and the same RPM principles applied.

The ONLY reason you are getting away with it now is because the ESCs have gotten MORE robust, and will handle more abuse. The motors haven't really changed, and these RTR motors can't really be considered the prime example of "quality" motors. Better than previous RTR motors, but not a Lehner or Neu.

But, hey, what do I know.

Just because YOU can't do it, doesn't mean it isn't done.

[Darin Jordan]

I have a data logging mgm Esc in mine. Haven't pulled the logs yet. Pull them tonight. They won't be an accurate representation however. The boat was ran in some nasty seaweed water and only had a top speed of 44mph on 6s.

OK, well when you get some clean data, let us know.

I'll have a look at mine tonight.

I just want to see how the RPMs are under a given load.

[kfxguy]

Yeah... OK... I'll keep that in mind.


I think I should just stop testing/designing/developing and racing boats because I'm a little too behind the times.

Not sure how my 1500KV powered IM31 can outrun a 2030 powered Revolt... maybe I just imagined that.

Newsflash... We were running Neu Motors 10-Years ago.... They were MORE powerful and MORE robust back then, and the same RPM principles applied.

The ONLY reason you are getting away with it now is because the ESCs have gotten MORE robust, and will handle more abuse. The motors haven't really changed, and these RTR motors can't really be considered the prime example of "quality" motors. Better than previous RTR motors, but not a Lehner or Neu.

But, hey, what do I know.

Just because YOU can't do it, doesn't mean it isn't done.

Id be impressed if you can make this hull do 60 on 4s reliably with all stock components. It sounds to me that's what your saying you can do, so let's see it.

[Darin Jordan]

Id be impressed if you can make this hull do 60 on 4s reliably with all stock components. It sounds to me that's what your saying you can do, so let's see it.

I'll give it a try, but I need to see the RPMs under load first. I also want to see the amp draw of your setups at those speeds.


And I didn't exactly say that... I said "reasonably close". There are efficiency of the prop issues that come into play as well that RPMs do make up for. The solution isn't always just a "bigger prop" (whatever the heck that actually means).

[kfxguy]

Pulled data log. Glad I did. Was only getting about 83% throttle. Need to recalibrate I guess.

Max amps seen was 123a and it was more around 115 when levels off.

Just realized I had it set to 4 pole also. Not sure it that makes a difference in power or heat but I know it does in the data log. Just ran another after fixing the throttle and it's getting 100% now.


I changed the trim tabs tonight and since I had to remove the rudder to do it I went ahead and put a different rudder on it with a kick back feature. Last lake I ran it made me nervous that I was going to break the rudder off because it has no break away. So now I feel better about it. Kintec sells these rudders so it's nothing special. Same exact length as the sticker and the same width. I think the trim tabs are going to allow me to dial it in much easier. I'll report back after I run it.

[Tamelesstgr]

Excuse my ignorance, but how do you set the throttle position? Assuming you are using the standard surface radio that is included?

[montymike]

Pulled data log. Glad I did. Was only getting about 83% throttle. Need to recalibrate I guess.

Max amps seen was 123a and it was more around 115 when levels off.

Just realized I had it set to 4 pole also. Not sure it that makes a difference in power or heat but I know it does in the data log. Just ran another after fixing the throttle and it's getting 100% now.


I changed the trim tabs tonight and since I had to remove the rudder to do it I went ahead and put a different rudder on it with a kick back feature. Last lake I ran it made me nervous that I was going to break the rudder off because it has no break away. So now I feel better about it. Kintec sells these rudders so it's nothing special. Same exact length as the sticker and the same width. I think the trim tabs are going to allow me to dial it in much easier. I'll report back after I run it.

Hey, can I get part# for the mods,knowing you had to drill and refill holes.