Flightline 1600mm Corsair motor swap

[FLY BOY]

Greetings from the PNW,

I recently purchased the Flight line 1600mm Corsair. I'm very happy to say the least. I can run FLAT OUT for 7 minutes straight on the Admiral 6s 6000mah pack and land at 3.75 volts per cell, and up to 10 minutes with throttle management with ease. Now that I'm used to it, looking for a power upgrade. I HAVE THE NEED FOR SPEED!!! I'm hearing about the Flightline 1600mm Spitfire motor is the ticket. Cant find any info in the official Flightline 1600mm Corsair forum. Here are the claims ---- Plug and play direct fit --- No prop change required --- Better climbing power --- Faster straight line line speed --- Flight times are about the same --- No ESC change required. Are these claims true? I found motor specs for the Spitfire, But no listing for motor specs on the Corsair. I would like improved performance for sure, But I would really like a screaming 4 minute motor at 95mph to 100mph as well. Who's got answers?

[OV10]

Where are you hearing this claim from. I would be very scheptical and say not true.
The Spitty motor with it's 50Kv increase is certainly not going to achieve the speed gains you are looking for.
With the higher Kv along with the Corsairs 2 inch bigger prop you will certainly be over taxing the motors spec'd power rating.
There are members on this forum that are STILL waiting a year for a release of the Corsair motor spec per this 11 post thread.
(I suspect based on the ESC size on the Corair that it's stock motor power rating is about the same as the Spitfire motor)
Here is some more input for questions like yours from better than a year ago.

[FLY BOY]

Some of the info came from the Motion RC review page for the Spitfire motor. People have bought and put them in there 1600mm Corsair, and claiming a speed gain. Then giving it a 5 star review as well. I posted for the same concerns you have OV10. The math is not right. I dont believe after seeing the specs, The Corsair prop will work with out over amping the Spitty motor. I will be performing an amp, watts test on my Corsair on my next day off from work, and compare them to the Spitty motor specs listed. I realize the speed gain would be moderate if its true. Maybe not worth the money even.

[OV10]

Some of the info came from the Motion RC review page for the Spitfire motor. People have bought and put them in there 1600mm Corsair, and claiming a speed gain. Then giving it a 5 star review as well. I posted for the same concerns you have OV10. The math is not right. I dont believe after seeing the specs, The Corsair prop will work with out over amping the Spitty motor. I will be performing an amp, watts test on my Corsair on my next day off from work, and compare them to the Spitty motor specs listed. I realize the speed gain would be moderate if its true. Maybe not worth the money even.

I usually know all about those reviews but I have no idea what review you are referring to for the Spitty motor
Trust me...………...I'm like the resident power modder on this forum and you'd be wasting your money using the Spitty motor with the Corsair prop.
As you commented about the math not being right, so you must be aware/know that the power coefficients are exponential when increasing any one of the prop dia/pitch/blade count factors.
The motor will be stressed and the performance increase barely noticeable. If you really want to go fast then seriously look at putting your money at a 8S power set up.
Happy modding

[FLY BOY]

Humor me OV10, Go to Motion RC Warbirds, Click on the 1600mm Spitfire. Click on spare parts, scroll down to the Spitty motor and click, scroll down to reviews. First review header states, Perfect motor for 1600 Corsair. and then go'es on from there.

[OV10]

Humor me OV10, Go to Motion RC Warbirds, Click on the 1600mm Spitfire. Click on spare parts, scroll down to the Spitty motor and click, scroll down to reviews. First review header states, Perfect motor for 1600 Corsair. and then go'es on from there.

OHHHHHH that review section The very last one dated 03/09/2018 is by yours truly but on a different config for a ASM 93" A-26.
Guess it is gonna come down to you doing a power test with that 18 inch prop cause those reviewers didn't provide stats to back up the claim like I did for what I was doing.
Happy modding

[redbarn]

OV10,
I mounted up a Leopard 5065 380KV motor to my Hellcat with the Corsair prop on it to see what it did and it pulled like 2200 watts static. I can only assume that the motor actually is a 380KV. I was afraid of melting my watt meter. Much too much prop for the extra rpm's. I have a 120 amp esc in that thing so it was a good plane to test it out. Unreal thrust though. I even shortened the blades by a whole inch and it pulled around 90 amps. I don't think this size of motor could safely run that prop unless it is no more than a 350 KV and that's really pushing it and not worth the trouble. I think the stock 340kv motor pulled 65 amps. It works okay you just have to keep it revved up and don't fly over 5 minutes.

[FLY BOY]

A friend in our club has a pocket radar and likes to see how fast his planes are. He is saying pretty much what you are OV10. Flightline has done an excellent job at maximizing the 6s system for the 1600 Corsair. Its going to be very difficult to get more speed with out going to 8s. After I do the amp, and watt draw test, were going to break out the radar gun and see just how fast it is. The claim is 75mph, but like my friend reminded me. Because of the Corsairs size, it appears slower than it actually is. It is plenty fast for its size, and has plenty of power to perform. Im actually very happy with it, but my problem is that I'm an extremest. I have actually disintegrated RC Aircraft in flight before by taxing the air frame beyond what it can handle. I dont think I want that to happen with this warbird that I paid a shiny dime for. So until all the testing is done, I wont be modding anything. But I am looking forward to posting the test results. Its the rainy season here right now, and rain is expected all week. So its going to take some time for all the results to come in. Happy landings from the PNW

[FLY BOY]

So hears what my meters are saying on my Corsair. Stock 3 blade prop, 6s 6000mah batt fully charged. I came up with 58amps, and 1320 watt static draw. The Spitty motor specs say its only 900 watts. So in theory the Corsair 3 blade prop CANNOT work on the Spitty motor. If they say they are, I call BS. Its a fire ball waiting to happen. Pocket radar test coming next week end.

[FLY BOY]

I think I made a discovery. I cant help but ask the question, Why such a big ESC if the motor draws only 58 amps. ESC rates at 80 amps. Then it dawned on me that I've seen this pattern before. Rock Hobby P51 Strega. It has a 70amp ESC and only drew 48 amps. Remove the 10x8x4 prop and add a 11x12 single blade and the amp draw increased to 58 amps. The speed increase was 15mph making the Strega top speed at 100mph. Its a text book mod recommended in the manual. The Corsair top speed is 75mph, and so a prop mod that would draw 10 more amps in theory should make the Corsair a 90mph bird. That would be perfect!!! The problem to over come though is theres no pitch to increase. Already a 18x12, the only choice is a longer prop. Things that make you go hummmm

[OV10]

It's called a safety factor. Electrical designers will always use 20-25% margins on power calcs.
You certainly do not want a power source ( ESC) with the same rating as the load (motor)

Regarding your hypothesis on "prop mods in theory"...…….go back to my comment in post #4

"power coefficients are exponential when increasing any one of the prop dia/pitch/blade count factors".
The difference between exponential and linear is where the novice in power mods gets themselves into trouble real fast.

[FLY BOY]

Oh I agree about the safety factor. But some power systems like the Roc Hobby P51 Strega were designed for a prop mod. To my experience on most rc aircraft theres always a 12-15 amp cushion to esc rating to be safe. The strega has a 22 amp cushion before the recommended prop mod by the manufacture. After you prop mod the Strega your amp cushion is 12. I dont know where you got the 25%, and I can honestly say I've never read that. But I have read that you always want your amp draw to be no closer than a 12 amp split according the esc rating. I have experimented with this theory with great success and letting the smoke out of a few esc's along the way. Even with just a 12 amp split the esc does run warm on any air craft and thats when cooling mods and esc placement come into play. Any closer to the esc rating has always turned into a fire ball with me even with a cooling mod. For me txt book is all theory, but when you put the rubber to the road, thats when I get real performance results. If there is a 25% safety margin written in a txt book some where, its most likely a recommended safety margin. Personally, and speaking from experience, My entire hanger of RC Aircraft are running a 15 amp split to esc rating. My esc's run cool, and any closer of a gap in my opinion they run to warm for my liking. We all know heat kills electronics. I always check my esc and batt's for heat after every flight on all my air craft. Then a just accordingly. And with these facts all in mind, and with a 22 amp cushion on the 1600mm Corsair, Well I will post my results. Even if I end up letting the smoke out. ( lol ) I just dont know if I can bring my self away from the scale appearance of the 3 blade look. Thats gonna be the real issue. Your thoughts?

[OV10]

My last comments since you asked for thoughts.
If you google power coefficient SF (Safety Factors) you will get a boat load of responses that talk about the SF being on average 25%(which is what I stated earlier 20-25%)
And that 25% (since you don't know where I got it nor have never read it) is right out of the National Electric Code (NEC) as just one particular source.

The code specs the maximum continuous current should be 80% of rated capacity, so the required rated capacity (minimum) can be found by multiplying the continuous current by 1.25 (or 125%).
When you say that text books are all theory for you, that's probably because you really believe it be theoretical because it doesn't bring practicality for you due to not having knowledge of the science behind it.
Theory is a set of principles on which the practice of an activity is fact based which IS how the rubber hits the road.
Every engineering formula is based on time tested fact based theory.
SO...……... you can use the formulas to design your power systems or you can continue to haphazardly playing in the sandbox of "lets let the smoke out"
Good luck

[FLY BOY]

I think you missed the point. The code specs the maximum continuous should be 80% of rated capacity is a tested and true science I agree. BUT now dont miss this, It is a safety parameter designed that allows a electronic system to work with out over loading AND is a base line maximum, NOT an absolute maximum. The 80% rule was designed so that ANY engineer can SAFELY design and OPERATE what ever the device is intended for. So maybe ask yourself before insulting some body for playing in the sand box, How did they come up with 80% rule? By playing in the sand box and letting the smoke out. The sand box is where castles are designed and built. Pun intended. I know of 3 RC Aircraft that DO NOT used the 80% rule. Hobby King Grand Tundra draws 78 amps on 6s using a 80 amp rated ESC. You can check Youtube on that one. My FMS P40 War Hawk drew 67amps on 4s using a factory 70 amp rated ESC. I swapped it out for an 80 amp ESC to maximize the safety factor. So yes I have read what your talking about, its been a long time since I've heard anybody talk like you, and it took a minute for this old guy to remember. I worked in the auto industry for 35 years.Electrical was my favorite.

[JamesonC]

I think you missed the point. The code specs the maximum continuous should be 80% of rated capacity is a tested and true science I agree. BUT now dont miss this, It is a safety parameter designed that allows a electronic system to work with out over loading AND is a base line maximum, NOT an absolute maximum. The 80% rule was designed so that ANY engineer can SAFELY design and OPERATE what ever the device is intended for. So maybe ask yourself before insulting some body for playing in the sand box, How did they come up with 80% rule? By playing in the sand box and letting the smoke out. The sand box is where castles are designed and built. Pun intended. I know of 3 RC Aircraft that DO NOT used the 80% rule. Hobby King Grand Tundra draws 78 amps on 6s using a 80 amp rated ESC. You can check Youtube on that one. My FMS P40 War Hawk drew 67amps on 4s using a factory 70 amp rated ESC. I swapped it out for an 80 amp ESC to maximize the safety factor. So yes I have read what your talking about, its been a long time since I've heard anybody talk like you, and it took a minute for this old guy to remember. I worked in the auto industry for 35 years.Electrical was my favorite.

Let's not forget, that plane originally shipped to customers with a 60a ESC in it! So, using that is more of an example of poor safety margins and bad practices. They had to go back and send customers a free 80a ESC afterwards. Even then, it is still over propped and they burn motors up. I burned one up and decided to finally take others' advice and prop it down. Essentially, they got that power system pretty wrong.

[FLY BOY]

I totally agree JamesonC. Complete and total lack of following any engineering guide lines and principles. And whats even more disturbing, Its not really fixed. The Grand Tundra is better, But is still falling out of the sky after a hard long run on 6s. There is a 100 amp ESC available but you wont get the option of reverse. The 80 amp version is the biggest one they make with reverse that I can find.

[FLY BOY]

So I did some testing last night using My FMS P51 Mustang with the P40 upgraded motor. I scared the crap out of myself too. The purpose was prop testing a single blade in the place of the 4 blade to establish a base line for the 1600mm Corsair. The P51 has the 14x8x4 blade prop with the zip tie pitch mod. Making it in the ball park of 14x12. Because I was unable to gain any pitch and only option was longer just like the Corsair would be, The blade would half to be significantly longer for any real performance gain creating a prop ground strike condition when the tail lifts on take off. Changing the Corsair to a single blade is a bust for now. I chose to test on the P51 because I already had 15 and 16 inch single blades in the drawer. I only spent my time which was very fun to say the least. Playing in the sand box is a hell of a lot of fun.