Official FMS 1400mm P-51D V8 Thread

[Shirty]

Managed to get flight no 2 today with BBD. A stunning morning here with next to no wind. Had another fantastic flight and avoided the left hand torque roll on take off this time. Greased the landing again so all in all a happy Chappy. 2 flights with no broken bits is not a bad start. Also i feel like she may need a bit more oomph so will be looking at the zip tie mod to see how that helps. She definitely makes the C182 feel a bit sluggish though. Amazing how I've flown that for over 2 years and felt like it had plenty of go and now after 2 flights with the stang I just want more power!

Stang heads, stang heads, stang heads...

Grats rod. That's awesome, sounds like you are doing well with the 51. :)

[KiwiRod]

I'll have to take a peek inside and see what it is running, I've not bothered to look so will let you know. I did however have a spitfire and a mustang fly low over my house yesterday which was a bit of a thrill. They were returning north from the warbirds weekend down south at Easter. What a sight and sound. You just don't see that every day!

[olwarbirds]

I caught a new Airborne disease, FWS .. Flight Withdrawal Syndrome......

[KiwiRod]

I've just had a look inside BBD and is running 540 kv motor and 70a esc. Does that explain the ok but not awesome power?

[Mizer67]

I've just had a look inside BBD and is running 540 kv motor and 70a esc. Does that explain the ok but not awesome power?

I think the official term for the 540kv motor in the P-51D is, "slow as molasses".

I pulled mine straight away and put in the 550kv motor running on 6S. She'll move along pretty good and full bore, but this big, draggy airframe will never be extremely fast running scale 4-blade 8 or 9 pitch props. I had a buddy of mine clock mine at 115 kph/72 mph, recently in level flight, which still isn't what I'd call "fast".

If you have access to one, I'd try the 650kv motor if you're sticking with 4S power. You'll probably need an 85+ amp ESC with the 4-blade prop. but I've been pretty impressed with that motor on 4S in my P-40B.

[Shirty]

I've just had a look inside BBD and is running 540 kv motor and 70a esc. Does that explain the ok but not awesome power?

Yep. I also run the 550kv upgrade in mine, mixture of 5s n 6s. On 4s the 650kv is the go. :)

I get around the same as mizer on top speed tests with a radar gun. About 116km/hr average with the 4 blade stock prop.

[KiwiRod]

Sweet, I'll give my man a call and see what he's got. Are you using an FMS motor or something else?

[wrongroad]

G'day Rod,
The 650 kv is the FMS motor in the new P40 and the 550kv is out of the FMS Olympus. [both 1400mm series]
Both are a near perfect fit with the motor mount and prop adaptor to suit the P40 or Olympus.
I think there is a little bit of surgery needed to fit the 550 and motor mount in the Mustangs but it is minor to fit the motor mount.
If you have a heap of 4S batteries and do not want to go 6S batts, then the 650 is the go. If you have 6sS batts the 550 is the donk to change to.
I like the performance of the Mustang on 4S and the 580kv but I will be going to the 650 soon [as I can save the $$$$] just for a little more.
I do not want a rocket ship but I think the power gain can not go astray either.
I would advise to upgrade your ESC as well just to be on the safe side.
Regards and respect
Daryl

PS, RC Castle is my preferred supplier of spare parts. Reliable and relatively quick service. Not many complaints on any forum about this company...in fact I do not recall any.

[KiwiRod]

Cheers Daryl

I'll have a look online tonight and check out costs etc.

[Grossman56]

Yeah, I agree with the 650kv, although you have to makes sure that you get the motor mount as well, found that out the hard way. I'll probably stick to the 580kv in my FMS Mustangs for now, but I put a 650kv in my FW with an 85A ESC. After seeing the P40B fly with the 650, I expect great things from this plane. It should help compensate for the extra weight of the sound system.

[xviper]

Yeah, I agree with the 650kv, although you have to makes sure that you get the motor mount as well, found that out the hard way. I'll probably stick to the 580kv in my FMS Mustangs for now, but I put a 650kv in my FW with an 85A ESC. After seeing the P40B fly with the 650, I expect great things from this plane. It should help compensate for the extra weight of the sound system.

I just ordered the 650kv motor myself. I wish to go back to 4s. I did not order any motor mount. Are you talking about the X-mount? I've got both the stock P-51 X-mount and the Olympus 550kv motor X-mount. Is the "motor mount" for the P-40 motor different from these two?

[Grossman56]

The bolt pattern on the motor is different, I can exchange 580 FW's and FMS's, but the motor mount doesn't fit on the 650 motor. I had to order one as well.

Grossman56

[xviper]

The bolt pattern on the motor is different, I can exchange 580 FW's and FMS's, but the motor mount doesn't fit on the 650 motor. I had to order one as well.

Grossman56

Crap! Why can't FMS standardize these things. All these motors are very close in overall size.

[wrongroad]

G'day viper,
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$$ is the answer my friend but you already knew this:D

The good thing with the 550/650 upgrade is that it will allow those with a heap of 4S batteries to go with the 650 and those with plenty of 5S/6S batteries can go the 550.
I believe that either combination gives about the same performance as the other. [standing corrected if needed:p]
A number of my club pilots want to know why I am looking at going for the 650. I really can not give them any other reason then 'I want to!' ;)
I have always been happy with the way my Mustangs have flown. I am worried that I might spend the dollars to find out that the performance gain was not as good as I thought it would be.
When I go the 650, I will be getting five motors to do the Mustangs and the two T-28's that I have as well. Then I will look at the F4U [V3] and others.
There is no substitute for cubic inches. What would that be in electrickery talk??? [no substitute for more windings ????]
Regards and respect
Daryl

[OV10]

What would that be in electrickery talk??? [no substitute for more windings ????]

Tim the tool man(Tool Time TV show in US) would say MORE WATTAGE

[xviper]

G'day viper,
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$$ is the answer my friend but you already knew this:D

The good thing with the 550/650 upgrade is that it will allow those with a heap of 4S batteries to go with the 650 and those with plenty of 5S/6S batteries can go the 550.
I believe that either combination gives about the same performance as the other. [standing corrected if needed:p]

Yes, but I was hoping for a more altruistic reason. The little red guy with the horns sitting on my left shoulder said just this, but the little guy with the halo sitting on my right shoulder said to give them a chance. :angel:
My reason for going with the 650kv motor is partially due to getting more use out of my 4s batteries. My 6s planes are increasing in number. The other part is that this flying season, I've noticed that with the 550/6s set-up and the stock 4-blade prop, something was cutting out near the end of the flight. I don't know if it's the motor overheating or the ESC hitting some sort of cut-off. This necessitates a dead stick landing. Luckily, I have a back-up RX battery but it's still an unnerving time. When I land and use the throttle again, all is well. When I go to the 2-blade prop from the Olympus, none of this ever happens. I prefer the looks and sound of the stock 4-blade. FYI .............. I'm using a 125A ESC so that should provide plenty of leeway.

[Mizer67]

The good thing with the 550/650 upgrade is that it will allow those with a heap of 4S batteries to go with the 650 and those with plenty of 5S/6S batteries can go the 550.
I believe that either combination gives about the same performance as the other. [standing corrected if needed:p]

I don't believe that's the case. They're closer when you compare 5S to 4S using the motor best suited for each, but 5S is still noticeably faster and has more thrust.

On 6S, there's really no comparison. A Mustang on 6S (using the 4258 550kv motor) has unlimited vertical and significantly faster top speeds in level flight. Nothing I've seen from the 650kv motor on 4S compares to 6S. It would be close if you ran the 4258 650kv motor on 5S vs on 6S for the 550kv, but your amp draw would be considerably higher using the 650kv.

The 650kv motor is the ticket for 4S though. Nothing else that I know of that's a (relatively) bolt-on replacement (from FMS) compares at the moment when you limit your voltage to ~16.8 max.

[olwarbirds]

Page 1 look at the links for each motor.... X that for sure sounds like a thermal shutdown, have you changed the timing on your esc ? even with 125 amp esc, if the timings off you will get amp spikes and overheating...

[xviper]

Page 1 look at the links for each motor.... X that for sure sounds like a thermal shutdown, have you changed the timing on your esc ? even with 125 amp esc, if the timings off you will get amp spikes and overheating...

That was one of the first things I checked. I have one of those ZTW programming cards where all the parameters are set with jumpers. I put all the settings to what I believe to be "normal" for this sort of application. I recall the timing was set on "auto" but I can certainly try "low" or "high" just to see. For the time being, it flies great with the 2-blade.

Looking at those links for motor mounts, it's hard to say without measurements how different they are. The P-40 X-mount looks kinda like the stock P-51 X-mount but with the holes closer to the center hole. I have the F3A mount and I know it's a bit bigger than the stock P-51. Maybe I can drill out the F3A mount to fit.

[wrongroad]

G'day Mizer,

I am not trying to compare the performance of a 650 on 4S v 6S.
I am looking at what package suits individual pilots who have heaps of one type of battery or another.
My very rough and quick calculations come up with similar results between 550/5S/6S combinations as it does to a 650/4S set up. Similar but not the same and anyone who has a stack of 4S would be better off going to the 650. If, on the other hand, you do have plenty of 5S/6S batteries, then the 550 set up is more logical.
If you want to make a screamer, then the 650/6S gives the rocket ship performance.
I am also basing my packages around the cost of doing such conversions.
As I have a lot of 4S batteries, it is logical for me to go with the 650 to get more grunt and speed.
To go with a 550 and 4S, would be a backward step as you would realize.
Here in Australia 5S and 6S batteries are getting too expensive and the freight is appalling to add insult to injury. For me to convert from 580/4S to 650/4S is the cheapest way for me to get more bang for the buck. It is also the only logical way as I have plenty of 4S but no 5S or 6S packs.
Hope this clears up what I am getting at.
Regards and respect
Daryl