1/8th mrx-4 brushless conversion

[ToolJeff]

I just bought a mugen mrx-4 on Ebay. I am wanting to convert with little effort and money yet remain reliable. Is it a good idea to have a pinion gear made to resemble a two speed clutchbell that slips on a motor shaft and secure with a longer setscrew? it would be a two speed electric, I know this isnt ideal bercause electrics make most torque @ 0 rpm's. aside frome the motor plate wich I have already designed and am making soon at work on my lunch brake. does anyone have any suggestions for my prodject? motor/esc/batt

[Mr. Constructor]

The esc should be able to go up to 6S Lipo (NiMh: 18 Cells) and should have a switched BEC to eliminate the needs of a receiver battery. The Amp readings for a 4WD 1:8 Buggy shall not less than 100A. The Batteries should be NiMh selected (as a minimum) or best choice: 4-6S Lipo setup. The Batteries themselve shal be able to withstand loads of up to 130A (for 20 sec or less) and should offer a Hardcase protection (if Lipos are used).

As for the Motor, this depends greatly on the gearing and Voltage you System should run on. Use the Nitro RPM as a standard Value: 30.000 RPM/Min. and then divide it by the Voltage of the Batteries you want to use. Now add 10-20% and then you have the Ideal RPM/V reading for a BL Motor choice.

[ToolJeff]

Ok i'll try that. right now im having alot of fun with this thing on nitro so in about a week ill start posting pics of the build up im not sure cause this car is CRAMPED for space so some engineering is needed just for battery location alone. are there any airplane lipo's with the same dischrge rate as the bigger hard cased 7.4 car batteries? Thanks Mr constuctor. that helped!

[Mr. Constructor]

No Problems, have Fun with it.

As for the Bettery choice (and the special "treatment for them) i would go for Kokams and us the 3200 mAh ones (or even bigger Capacity).
Others will work very well too, check out the dimensions as you might want to re-use these packs on normal 1:10 Cars too: 140x45x23 mm should not be exceeded as these sizes will also fit into many 1:10 Cars.

Check out the Major brands in your Hobby Shop for these Sizes, almost any Lipo Battery with minimum of 20C is able to deliver the needed power, therefore you will have plenty of power available AND have a wide choice of opportunities too.

I will start a new thread this day to show the people how to cover their normal Flight Lipos (any Lipo without a hardcase) with a easy and chep self-made housing. I will edit this answer to give you the direct link when i´m done.

Here it is:

http://forums.radiocontrolzone.com/showthread.php?p=2330882&posted=1#post2330882

[party_wagon]

Here is the absolute cheapest way to go.
***the right way to go***
esc-mamba max(remove the heat sink & mount a fan on top & bellow it)
***mamba monster max when it comes out***
motor-feigo 9XL(do a little research on how to keep these togather)
***neu 1512 series motor pick your d wind***
battery-4s2p a123 pack. A dewalt 36volt pack has 10 of the cells in it & can be purchased for like $120 on ebay.