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View Full Version : Article Castle Creations Mamba Competition X Motor and ESC 1/18th Scale Car Mini-T Upgrade Review


Jim McPherson
Dec 01, 2004, 02:00 AM
!Ready to burn some rubber

| spec2
| @911319
|> <b>Motor Diameter:</b> |< 0.79"
|> <b>Motor Length:</b> |< 1.3"
|> <b>Motor RPM/Volt:</b> |< 8000
|> <b>ESC current:</b> |< 25 amps
|> <b>Weight:</b> |<Motor= 1.7oz, ESC 0.7oz.
|> <b>Battery:</b> |< 3 Cell Apogee 830 / IRate 2200 LiPoly
|> <b>Manufacturer:</b> |< <a href=http://www.castlecreations.com>Castle Creations</a>

I've had my Mini-T for quite a while. From the moment that I ran it for the first time I've wanted more speed. I tried everything. First I upgraded the battery to a 3 cell Lithium Polymer pack. The stock motor didn't last long on the extra voltage. So next I installed a GWS 350C motor and got a good increase in top end speed over the stock 280 motor, but not enough. Still wanting more, I went brushless and installed a HiMaxx 2025-4200, then a MPJet 2535-20. In order to run these brushless motors I had to use an ESC designed for an airplane. This made operation of the car difficult and a lot of hassle. Despite the difficulties, the added speed of the brushless motors was addicting. After racing and easily defeating many large, nitrous powered cars, I was feeling pretty good about how my Mini-T was performing... if only I had a nice lightweight ESC made for a car.

Enter the Castle Creations Mamba. Designed from the ground-up to be a car ESC, the Mamba was seemingly exactly what I had been longing for. But would it live up to its promises? Would it be plagued by bugs that often accompany a new product? I had to know the answer to these questions. So thanks to Castle Creations I got a hold of the Mamba Competition X package. It included the Mamba controller as well as Castle's new line of brushless motors built specifically to make small RC cars speed.

!Meet the Mamba ESC

@911320: The top side of the Mamba ESC.
@911321: Underneath the Mamba.

The Mamba ESC is a small package, about the same size as a Castle Creations Phoenix 25. Like most CC products, it performs very well and has an amazing amount of configurable options. One great feature of the Mamba ESC is its performance at slow speeds. I've never seen an ESC perform so well while starting up and at slow speed. I've read many debates on the "advantages" of sensored motors and how much better they start up and perform at slow speed. The Mamba eliminates that advantage and makes sensorless motors perform just as well as sensored. This is a huge achievement in ESC technology, and I was thrilled that Castle was able to bring this feature to their ESC's. In addition the Mamba link software (shown below) allows modification of the throttle and brake curves. The variable curves allowed setting the response of the ESC to an individual driving style and the performance of the car. The flexibility of this controller was astonishing.

!Mamba Link Software

One great product offered by Castle Creations is their USB-Computer interface. It gives the user the ability to control every aspect of the ESC's configuration from a nice graphical user interfaced on their PC. The Mamba worked with this interface via the MambaLink software. MambaLink gave me the ability to upgrade my Mamba firmware, change the throttle and brake curves, throttle types, cutoff voltage, reverse percentage, motor timing, and start power. It was a very nice feature that made ESC setup simple and much less confusing than counting beeps as most controllers do. I plan to use one ESC in multiple vehicles/motors and the USB interface is an absolute necessity.

@911322: Basic setup of the ESC in MambaLink.
@911323: Setting the throttle and brake curves in MambaLink.
@911324: Upgrade the firmware of the Mamba from here.

!Mamba Competition X Motor

@911325: The Mamba Competition X motor.

The motor was a nice little brushless motor. It looked similar to the Himax brand motor but seemed better made. It had a neodymium rotor and a VERY high RPM/V. The 8000 RPM/V was higher than any other hobby brushless motor that I've used. That was great for high speeds but could still deliver high torque when geared high. It was interesting to note that the motor shaft had been turned down from 3mm to 2mm. The only reason I could think of for this was to allow 3mm bearings which might be a bit more robust than smaller versions.

!Installing the Combo

@911319:The complete combo contents, including motor, ESC, switch, mounting screws, and instructions.

!!Installing the motor:

@911326:The tiny brushless motor was very easy to mount. Castle put a variety of different mounting configurations on the Mamba so that it would easily fit in almost any car and motor mount.

Before the review I had hacked up my stock Mini-T motor mount plate to fit the previous motors into it. For the review I ordered another mounting plate with stock bolt placement. The Mamba motor fit in perfectly and required no modification to mount with the included screws (a nice touch).

@911327:The new stock spaced motor mount.
@911328:Mamba Competition X Motor mounted, super simple!

!!Installing the ESC

Installing the ESC was (of course) super simple. I fed the connectors from the ESC through the supports of the frame and connected them to the motor. Red to red, white to white, etc. Thanks to Castle Creations for making the motor rotate correctly when identical colored wires are connected. With a little double stick tape on the tray above the battery, the ESC mounting was finished. Piece of cake.

@911329: Installing the ESC with a little double stick tape.
@911330: Next the ESC switch needed a home.

I wanted to install it so that I could access the switch with the body of the Mini-T on. I decided to put it on the front of the car behind the right front wheel.While this position did allow me to turn the ESC on and off with the body on, its location was not ideal. When driving through rough ground the switch often got flipped by debris on the ground. So if you plan to use the Mamba mainly off road, I'd suggest a different mounting position (or perhaps leave the switch off).


!Too much speed?

When I first ran the motor up I was in awe. The rear wheels spun so fast that they narrowed and almost doubled their diameter from the centrifugal force. That was cool, I started laughing... literally! At this time I was running the stock pinion that came off the original speed 280 motor.
With that kind of RPM I was worried about the slow speed characteristics of the motor. On the MPJet 2535/Hacker 18P combo, the Mini-T was fairly fast but really suffered at slow speed and stuttered each time it started moving. The slowest speed of the 2535/Hacker 18P was about 10MPH. That was pretty fast for the Mini-T and it was annoying to be forced into such a high minimum speed. I swapped down to the slower Himax 4200/ Castle Creations Phoenix 25 and while it started more smoothly, it still had a high minimum speed and didn't go as fast as the MPJet combo. After seeing the HUGE top end speed of the Mamba, I was really worried about the startup and minimum speed of the motor in the Mini-T. Would it be "too much speed"?

!Too much speed? Yea right! Driving the BEAST.

I was pretty excited to take the Mamba out for the first time. I started off by testing the slow speed characteristics of the combo. I was pleasantly surprised to find that the Mini-T/Mamba Competition X was able to start very smoothly with none of the rough jittering I experienced with the MPjet/Hacker combo. The Mamba was also able to putt around very slowly. The video below starts out showing just how slow the Mamba Competition X could go. Remember that the Comp. X is the highest RPM/V motor of the family of Mamba motors, which means it should have the most difficulty moving slowly. I could attest that it has no slow speed problems at all.

After I tested it out at slow speed, I hit the throttle to see what would happen. The car quickly flipped over. So I flipped it upright and tried again... a little slower this time. Slowly applying the throttle and making sure I had a good amount of straight away, I ran the throttle up. I got better results and the little Mamba had instantly made my Mini-T the fastest RC car I've seen. This car was fast. There really wasn't any other way to describe it.

About half way through that first good high speed run, the car flipped over again. That happened quite often. In fact, I had to be very careful with the throttle. The overwhelming power of the Mamba combination had enough power to flip the Mini-T from the torque of the back wheels alone, at any speed. Compare this to the speed 300 motor that could only achieve a wheelstand from standing still. The video shows the ability of the Mamba to flip the Mini-T over quite easily.

!!Weighing Down the Mini-T to Keep it From Flying!
Another issue that arose from the speed of the Mamba was that at high speed, airflow under the car would flip it over. At what I estimated to be 45-55mph the Mini-T flipped over due to the air pressure underneath it. In order to stop the flipping I installed heavier batteries. I went from a 3 cell 830mah lithium pack to a 2200mah lithium pack. I had to modify the battery compartment to get the larger cells to fit. But a little time with the dremel tool and the battery fit perfectly. This helped the flipping issue and allowed a few more mph before the Mini-T would flip. I estimated about 60mph before it lifted off the ground and flipped.

The Mamba Competition X motivates the Mini-T beyond the physical capibilities of the chassis. While this sounded like a bad thing, it was the opposite. The Mamba powered the Mini-T to the limit of the car; this meant that in a Mini-T race my ability to win the race was solely based on my driving skills and not on the speed of my motor. With the Mamba there was no need for more speed, as it already was capable of more speed than the Mini-T could handle. The ultimate upgrade.

!!Suggestions to the Mamba/Mini-T Driver

I quickly learned that I needed to increase my driving skills. The first 2 weeks that I had the Mamba in the Mini-T I broke more parts than I would care to admit. I also wore out the stubby, off road tires that the Mini-T came with. I'd suggest keeping an ample amount of spare parts (front end particularly) and upgrading to street tires when you put the Mamba in the Mini-T. That way you won't be down long when starting your way up the high speed driving learning curve. Another side effect of the high speed is that the Mamba will eat gears almost instantly if the gears are not perfectly aligned. For this reason I suggest putting a little blue locktite on the screws that hold the Mamba to the motor mount. If those screws get loose while driving and the Mamba moves even a millimeter you'll instantly strip gears. Everything on the Mini-T has to be in top condition when you put in such power. Another example is the nuts that hold the tires on. While driving around a nut got loose and my left rear tire came off. Below is a picture of where and how the tire stopped.

@911331: Good thing that leaf stopped the rolling tire!

I suggest upgrading to the oil filled shocks as well. High speed turning becomes much easier and rolling the car almost stops completely with the oil filled shocks. I'd consider them almost mandatory if upgrading to the Mamba Compition X.

+911332:The Mamba power Mini-T. Note how slow and how fast it can go on the same pinion.

!Conclusion

The Mamba ESC from Castle Creations is a fantastic speed control for the 1/18th scale cars. It offers amazing performance, excellent configurability, and superb slow speed performance. The Mamba Competition X motor will accelerate a Mini-T faster than the Mini-T can handle. After the Mamba upgrade there is no physical way (limited by the chassis) to further increase the motor speed. I highly suggest the Mamba to anyone with a 1/18th scale car. Your friends will be amazed at the unbridled speed the Mamba offers. You'll be amazed at how much better a driver you become after tearing it up with the Mamba. It is strangely exciting to see a little rocket flying along at 60mph+. It is the ultimate upgrade and is well worth the money.

Fred Bronk
Dec 01, 2004, 03:24 AM
Jim, I know how you feel! :D

I have the 6800KV, I figured 50mph was enough :o

A 8000kv does have an aero problem, we just need wings!!

FB

j_z_123
Dec 03, 2004, 11:58 PM
Any more pics of the Modified Battery tray?

Also, did you upgrade your TX, RX, and Servo Like Castle Recommends? What are you using??

Jon

Jim McPherson
Dec 04, 2004, 03:35 PM
Yes, you must swap out the Tx/Rx/Servo if you want to use the Mamba since the stock Mini-T uses an all in one brushed ESC/Rx and the servo has a funny 4 pin connector. I pulled out that mess as soon as I got the Mini-T about a 8 months ago.
I used a bluebird 9 gram micro servo and a HPI RX-2 micro Rx/Tx.
I don't currently have any pics of the battery tray, but can snap some this evening. All I did was cut out the sides of the tray to allow for the big 2200mah pack to fit in.

-Jim