I want to purchase a back up ECM for my 1985. I have a 4+3 do I need to find one that is specifically programmed for a MT? Are the numbers on the ECU different for a MT vs AT.

Thanks

 

you have a 1226870 ECM. The ECM no.
It is the Prom Carrier. Inside. That is Specific. Auto VS Manual. Along with many other tables.

 

Thank you that is what I figured. I know many people upgrade to an 86+ ECM, is that a wiring nightmare?

 

Not so much a nightmare. you can easily get the wiring schematic & pull and re-pin the wire differences. I was going to mention this. But it appears you were already aware / consider this option. A few more tables to tune. If you have a moded engine. Plus this ECM is more available. Also more bins available.
It's actually fun. I have a 94 parts car. I upgraded my fuel pump wire gauge from OE 18g to 14g & 14g to 12g at the fuse block. Gained over 1 volt. experimented on the parts harness 1st. The funny thing is GM had larger connectors to accommodate this gauge wire. But used $$$ saving thin gauge wire.

 

Skinnier wire is also lighter in weight. There is more than one factor to be considered here.

 

This is true. Very minimal weight savings in 1 car. I could see the savings in production.

OTOH. The drop in voltage using the Skinnier "wire" is not so good on the brush motor FP. In this case more Voltage is better!!!! and actually adds more volume to your GPH & pressure. Resulting in a small HP gain. And much less stress on the FP.

 

I think you mean is more current, amperage, which does the work in those devices. Small point, yes.

 

All of the above. Applies. A lil more detail. FWIW.

DC Motors are generally used in lower voltage applications where portability is the primary goal. Most DC Motors have brushes to switch the magnetic alignment to cause rotation. DC Motors operate over a wide range of voltages. A 12V DC Motor will operate down below 6V or up to over 15 or more. What is lost at low voltage is speed & torque. At a lower voltage, both friction and load will drop motor speed. Thus a DC Motor rated 1200RPM at 12V at no load will drop to near ½ Speed at 6V and torque will be much lower. At a high voltage the speed & torque will be higher but the DC Motor upper voltage range is limited by rotational force & heat. The best way to lower a DC Motor speed is through the use of Pulse Width Modulation (PWM) where full voltage is applied (therefore full torque available) but only for a adjustable period of time. The load will cause the DC Motor to slow to an average lower speed. Without increasing voltage above rated; the max speed & torque with PWM is the rated value. A DC Motor with Gearhead is another method to increase or decrease speed range and resultant torque.