Yes it will be great if you get a controler for the combined current intensity of both engines.

If you improve the refrigeration/dissipation of the controler it will handle more punishment without problems

Ricardo

OK. Understood.

So, what your telling me is that if i get a speed controller rated for the combined amperage of the 2 engines this will solve the problem?

As this will allow for more current flow. I can now add two 7.2v batteries in parallel. The bigger speed controller will handle the initial current and pass it through to both engines.

Can extra heat sinks help with the heat dissipation and prolong the life of an under-rated controller?

I agree with the parallel battery config, much better than raising the voltage in series.

Scott
Davo

Ok lets proceed by parts.

The speed controler must be a solid state (Power Transistor) controler. If it is designed for just one engine a current I (I=V/R where V is the voltage at engine terminal and R is the engine electrical resistance) will flow on it.

This current will cause the power transistor to dessipate some heat.

If you conect two engines to the same controler you will get half of the previous elec. resistance or twice the previous current. This will make the controler to dissipate more heat (and eventualy burn). Ok, but it will work, but may be just for some minutes.

If up to this you increase the voltage by a factor of two the disaster is guaranteed.

If your problem is just the power demand (the batery time) it will be better for you not to increase the voltage but to increase the Ah. If you conect two 7.2V batery pack in paralel (+ to + and - to -) you will get something like the double of the time. The aceleration and the speed can be even superior because you will get less voltage drop.

I hope it works and helps you.

Ricardo

Ok. Since im into modifying things i've been given a remote control car to play with. Its a decent size car with a 13 turn race engine. Has no speed controller or reciever.

My idea is as follows.

Hook up 2 electric engines. I have done the modification to the car itself and can sit 2 engines in side by side running onto the same cog. This cog spins the rear diff and has a shaft running up to the front diff. So, all the mechenical stuff is done.

My problem lies here.

The speed controller. Im guessing the speed controller is just a variable resistor. But getting a speed controller to handle 2 engines may prove a problem. If the speed controller is just a variable resistor, i dont see why i wont work. But, the supposedly professional hobby shop guy rekons it wont!!

Ok. Now the standard battery pack is a 7.2 volt unit. I want to run either 9.6volts or 12 volts and double the original amprage. I need this power upgrade as 2 engines will drain a 7.2 volt pack in 5 mins. So, i need a speed controller to handle this amount of power into it and out. Again, the hobby shop guy rekons it cant be done!

I beg to differ. Some model planes run up to 12v so what speed controller are they using? Obviously one that can handle 12v. If i wired up a 12v speed controller, powered by 10 1.3v nicad cells this will create enough energy to give me the desired voltage and amprage. I then take a split of the output and run them to both engines. This should provide the engines with enough power to work. Right?

This modification should make the car hoot. I will gear it all down once working to find more top speed but for now i just want to get both engines running of the same speed controller.

Any input? I know it aint Datsun related but hey, its still modifying a car!!!

Scotty
Davo