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Navy Diver
Dec 27, 2004, 02:00 AM
| spec2
| <big> CC's Mamba Package </big>
| @913121
|> <b>Motor Size:</b> |< 0.79 dia x 1.3"
|> <b>ESC Size:</b> |< .95 x 1.72 x 0.4"
|> <b>Motor Kv (RPM/Volt):</b> |< 6800
|> <b>Motor Weight:</b> |< 1.7 oz
|> <b>ESC Current:</b> |< 25 Amps
|> <b>ESC Weight:</b> |< 0.7 oz
|> <b>Battery:</b> |< Apogee 2 Cell 1050, 3 Cell 830
|> <b>Manufacturer:</b> |< <a href=http://www.castlecreations.com>Castle Creations</a>
| <hr>
| <big>Horizon's Losi Mini-T</big>
| @913122
|> <b>Length:</b> |< 8.6"
|> <b>Width:</b> |< 7"
|> <b>Wheelbase:</b> |< 5.6"
|> <b>Height:</b> |< 3.25"
|> <b>Suspension:</b> |< Independent front and rear A-arm
|> <b>Drive Train:</b> |< Gear-driven transmission with slipper clutch
|> <b>Tire Type:</b> |< Rubber ribbed tread w/ foam inserts (front), Rubber Mini-pin tread w/ foam inserts (rear)
|> <b>Manufacturer:</b> |< <a href=http://www.teamlosi.com>Team Losi</a>
|> <b>Available From:</b> |< <a href=http://www.horizonhobby.com>Horizon Hobby</a>

!Introduction
In my original <a href=http://www.rcgroups.com/links/index.php?id=4716>review article</a> of the Team Losi Mini-T, I evaluated the Mini-T in a strictly stock configuration (with the exception of the battery pack used). This second review was all about MORE POWER. The Mamba-25 brushless power package from Castle Creations is the ultimate upgrade for any 1/18th scale car or truck. The heart of the package is the Mamba-25 brushless speed control, and when paired with one of four CM20xx brushless motors, the upgrade package is practically plug and play**.

<i><small>**Assumes Mini-T owners have previously upgraded servos, Rx and Tx from stock setup. Mini-T installations MUST have a standard receiver (NOT the integrated RX/ESC unit that ships stock with the Mini-T) to control the Mamba Speed Control.</i></small>

!Kit Contents
@913123:Here was the package as it arrived on my doorstep.

@913124:Here is a look at the contents. You’ll note that I have already soldered a Deans Ultra connector to the ESC.

The Mamba-25 Brushless Power Package comes in a small 4 ½”x 3”x 2 ½” box. Inside, well padded on the top and bottom by foam, are the brushless CM20xx motor and the Mamba-25 Speed Control. There are four choices of Kv for the CM motor. The first is the 4200Kv Sport motor; next is the 5400Kv Performance motor; third is the 6800Kv Competition motor, and last is the 8000Kv Competition “X” motor. Simply put, all other things being equal, the higher the Kv, the faster the motor will run, the higher the amp draw, and therefore, the shorter the run time. Although, speed can also be adjusted by changing the gearing as well. For this review, I used the CM2068 (6800Kv) Competition motor.

!Other Replacements to Get the Best Performance

!!Receiver/Servo Replacement
In my review of the stock Mini-T, I recommended some minimum upgrades, including ball bearings and oil filled shocks. Additionally, the stock receiver/ESC unit is not capable of controlling a brushless motor, so that meant swapping out the entire receiver/esc unit for a separate receiver to be used with the Mamba-25 ESC. I decided to go with a Novak XXL receiver for its light weight and small size. With the new receiver, the stock steering servo was no longer compatible (4-wire plug on the stock servo, only 3 wire plug acceptable with the Novak receiver), so I swapped out the stock steering servo with a Hitec HS-55 servo and the appropriate servo saver.

!!Pre-emptive Parts Upgrades
Per discussions w/ Shawn Palmer at Castle Creations, I decided that, while I had the Mini-T stripped down, I should go ahead and replace the parts that had the highest failure rates during their testing at Castle Creations. These included the pinion gear, differential, turnbuckles, C hubs and steering hubs, steering kit, suspension arms, shock towers and servo plate. If it sounds like I am trying to bullet-proof the truck, you are right. I figure it’s a lot easier to go ahead and swap out the most fragile parts up front rather than to be continually dismantling the truck to replace them one by one. I elected to use aluminum and titanium parts from GPM Racing Products. Here are some photos of the components that were changed:
@913125:Here are the titanium turnbuckles and front and rear hubs.
@913126:Oil filled and threaded adjustable shocks for the front and rear.
@913127:Ball differential and titanium drive shafts along with new ball bearings for the wheels.
@913128:Front shock tower and lower arms.
@913129:Rear shock tower and lower arms.

!Assembly
Obviously, the first thing that had to happen was the disassembly of the Mini-T to get ready for the installation of the new components.
@913130:Here was the Mini-T before I started removing components.
@913131:Here I was about half way thru the stripping process.

Once the necessary components were removed, it was just a matter of rebuilding the truck using the new components. The CM2068 brushless motor bolted right up to the stock motor plate with the included screws. I chose to go with a 13 tooth metal pinion verses the 14 tooth stock plastic pinion. With the stock 60 tooth spur gear, that gave me a gear ratio of 4.6:1 verses the stock ratio of 4.3:1. By going with a lower ratio, I increased the torque but reduced the top speed available from the combination. For a higher top end speed, I could have used a 15 tooth or higher pinion, but didn't feel it was necessary. I recommend using a little loctite on the set screw to prevent the pinion from coming loose during operation.

@913132:Here is a look at the new lower arms, steering hubs and components installed.
@913133:Here is a look at the CM 2068 next to the stock motor.
@913134:The CM2068 bolts right onto the stock motor plate.
@913135:All new components are installed, waiting for the wheels.
@913136:Wheels are installed just waiting for the electronics.
@913137:Here is a close-up of the CM 2068 after installation. Note the air gap around the motor.

The Mamba-25 ESC and the Novak XXL receiver easily fit on the battery cover plate. They were both installed using double sided tape. The switch for the ESC was mounted to the left side of the receiver. The connection between the motor and ESC were simple since the bullet connectors come pre-installed from Castle Creations, and the wiring was even color coded so there could be no issues with the motor turning in the wrong direction.

@913138:The Mamba-25 and the receiver easily fit on the battery cover.

To program the ESC, I chose to use the new Mamba Link interface software. I already had the PHX-Link USB programming kit for use with my Castle Creations Phoenix Speed Controllers, so no new hardware was required. The PHX-Link plugs into the USB port of the computer and, with the Mamba Link software, allowed me to easily set all programming options for my controller. The software has only been released in a Beta version, but I didn’t encounter any problems using it at all. The simple user interface eliminated the need to count beeps and flashes while trying to program the ESC. I was able to quickly set the Low Voltage Cutout for the lithium-polymer batteries. Also adjustable are the brake/reverse type, the reverse throttle amount/brake strength, the motor timing and the start power. Another nice feature was the ability to customize my throttle and brake curves. The Mamba Link also gave me the ability to update my software as required.

@913139:Here is a screenshot of the Mamba-Link program. Note how simple it is to adjust the settings - no more beeps and flashes.
@913140:This is a look at the throttle and brake curves as they come set from Castle.
@913141:Here is another shot of the throttle and brake curves after thay have been softened up a little bit so the trigger is not so sensitive.
@913142:Updating the Mamba-25 software is only a click away.

An Apogee Lithium-Polymer battery, available from <a href=http://www.apogeepacks.com>PFM Distribution</a>, was my battery of choice for the Mamba-25 Brushless Power Package. Their light weight, compact size and superb performance under load made the Apogee Lithium-Polymer a perfect match. I used two different batteries for this review. The first was the Apogee 2 cell 1050, which was equivalent to a 6 cell Nicad or NiMH pack but at only half the weight. The second was the Apogee 3 cell 830, equivalent to 10 Nicad or NiMH cells.

@913143:Here is a close look at the Apogee 2S 1050.
@913144:Here is the Apogee 3S 830, which now includes a voltage port that allows you to check individual cell voltage <i>(sorry for the fuzzy picture).</i>

!Performance
Once everything was installed and connected, it was time to “take it to the track.” My first runs were using the Apogee 2 cell 1050 battery. Racing up and down the hallways at work very quickly got too small. So, it was outside to the parking lot. Words are not sufficient to convey the difference in performance offered by this Motor/ESC combination. Running up and down the parking lot, the Mini-T was incredibly fast. The Mamba-25 ESC worked like a dream. There was no stuttering on startup and acceleration was smooth throughout the travel of the trigger on my controller. The brake also functioned smoothly, and, after two seconds in neutral, the ESC would allow me to accelerate in reverse according to the setting programmed into the controller. The throttle had to be applied gently to prevent standing the truck on its rear end. It was possible to do a wheelie even when accelerating from half throttle. I had a buddy running his Mini-T which has been modified with a big block conversion using a 380 brushed motor and, even with a head start, I could pass him like he was going backwards.

After getting comfortable with the throttle, it was time for some speed runs. With the use of a police radar, we clocked the Mini-T at 25mph using the 2 cell lithiums. Then it was time to replace the battery with the Apogee 3 cell 830 and see what it could do. I thought the 2 cell lithium pack made the Mini-T fast, but with the 3 cell pack, it would really scream. Once again, I had to be gentle in applying the throttle to keep all four wheels on the ground. The Mini-T ate up ground so quickly that, with the 3 cell Apogee pack, even the large parking lot got small very fast. I’ve driven larger RC cars that were fast, but the scale of the Mini-T really gives the impression of speed. Once again we checked the speed of the Mini-T using radar and consistently saw 36+ mph. That was a scale speed of almost 650 miles per hour. Needless to say, at that speed, even a small bump in the pavement sent the Mini-T tumbling, and boy was I glad that I had invested the time in upgrading the stock components to something a little more durable. Further runs have convinced me that this was a good idea. What is the point of having all of that speed at your disposal, if you don't use it?

@913145:Here is a look at the radar after a speed run on the 3 cell Apogee pack.

!!Video/Photo Gallery
@913146:All tricked out and ready to play
@913147:Here is what can happen if you hit one of those irregularities in the parking lot going just a bit too fast
@913148:A little bit of sand blown in from the beach just meant more fun
@913149:Don't take those turns too fast or you'll be sorry
@913150:The mamba would stand on it back wheels even when accelerating from half throttle
@913151:Off to the races
+913152:The upgraded Mini-T races around the lot.

!Conclusion
As covered in my earlier <a href=http://www.rcgroups.com/links/index.php?id=4716>review article</a>, the Team Losi Mini-T gives big truck performance in a little package. But when you are ready to elevate that performance to the next level, the Mamba-25 brushless power package from <a href=http://www.castlecreations.com>Castle Creations</a> is the ultimate upgrade. Whether you intend to race your Mini-T, or you just want to have the fastest truck on the block, the Mamba-25 is just the ticket.

Capgun_Slim
Dec 30, 2004, 07:56 PM
Something must be wrong here. Information from directly from castle creations says that with a 2 cell you should be hitting 40mph, and with a 3 cell 50mph. I don't understand. 36mph with a 3 cell lipo? I'm sorry but something just doesn't add up. Maybe you never had it up to full speed, possibly due to the length of the parking lot? I've seen several videos with the 6800 in other mini-t's and they are going much faster. I'm not trying to urinate on your review, I think other than the speeds you were getting out of it, it was very good. I would like some answers though before I go out and buy one, due to the fact I wanted to get the 6800. But, if 36mph is top speed then I'm going to have to go with the 8000. I really don't want to go with a 8000 though, due to how undriveable it's supposed to be.

Flyingwing
Dec 31, 2004, 11:48 PM
He changed pinion gears... "13 tooth metal pinion verses the 14 tooth stock plastic pinion" " I increased the torque but reduced the top speed "

Navy Diver
Jan 03, 2005, 04:47 PM
Capgun,
In addition to changing the pinion, the Apogee 3S 830 battery is very light. I am sure with a heavier battery and different than stock tires (ie foamies for better traction) that I could have gotten more speed. Additionally, as you could see in the video, there was a lot of sand in the parking lot and any bump at that speed would send the truck tumbling. The 6800 is a great motor for this truck - I find myself using mainly the 2S lithium packs because the speed on 3S is almost unmanagable.

Capgun_Slim
Jan 06, 2005, 02:35 AM
Ok, I must not have seen that in the review, sorry. Now it makes sense. I'm actually going to be putting this in a RC18T and not a Mini-t, so it should be interesting to say the least. I should be able to hook up better with 4 wheel drive. I decided to go with the 8000 BTW. Thanks again for the review!

Flyingwing
Jan 06, 2005, 03:51 AM
I know some one that just got there 6800 and they put it in the 18T, dont know how its working yet.

Burrabbit
Jan 16, 2005, 10:19 PM
I have a 6800 in a stock rc18t and it runs just fine. :) i just put some trinity mini-T street tires on it which are a little bigger and it runs like a banshee 25-30 mph with gp1100 batteries. I plan on 2s lipos next. I have a buddy wiht the 18t and the 8000 with 3s lipos and he cant turn at more than half throttle without spinning or dumping it over. :) But, it goes really fast in a straight line.

Flyingwing
Jan 17, 2005, 02:19 AM
I just got a 6800 to put in my 18T, im using it with a 2s 2100 getting 20 min runtime speed about 30mph.

10boner10
Mar 14, 2007, 10:16 PM
Not quite sure what gear ratios get 30-40mph but I own a Mini-T that will do ~ twice that. I have installed a venom speed meter and calibrated it conservatively ( under-rating speed by a little for positive confirmation of speed). Running a 1700mha 3 cell LiPo and Mamba 8000 competition X system. I have on a number of occasions recorded a top speed of 115km/h (72mph!). The tallest gearing I could squeeze into the Mini-T recorded a free-wheel (off the ground) speed of over 210km/h (132mph), but it was over geared and It wouldn't go faster that 115km/h (72mph) so I geared it down to get near top rpm at 115km/h. I figured it should do just over 120km/h but I've played around enough and an going for a top speed with a mamba max 7700 in a Top fuel type dragster. Going to try a 3 cell LiMn 4600mAh from Apogee and see how we go. I know this motor is only rated for 2 cell LiPo (exceeding max RPM)but what the hell- I'm not after an extended motor life. I figure it will accelerate a lot harder, as did the Mini-T. The Mini-T has so much power that hard acceleration at 70km/h (~45mph) will result in a back flip, usually ending in some form of destruction of suspension parts. This same gearing (top speed) produced a hard enough launch off the mark to destroy itself from 1 yard into something solid (Yes, I have done so unfortunately). Only downfall with this system is you basically cant use full throttle, until it has reached about 3/4 of it's top speed, even then often resulting is some form of high speed crash. Actually,I'm kinda sick of 5 minutes drive then take home again for repairs. If this hasn't got enough power for someone, nothing will satisfy.

Sam77
Aug 24, 2007, 12:17 PM
Looking to do this mod to a Mini-T with the 8000Kv motor. Which servo saver did you go with for the HS-55 (or did I miss it in the article)?

Any other suggestions that you might have now that you've had a bit of time to run the car?

Thanks,

Sam

hondaman263
Dec 01, 2007, 09:22 PM
How much do you think it would cost to make the mini-t brushless(i'm talkin bare minimum)