I just rebuilt the 305 in my car I'm going from TBI to a 650 holley with vs and HEI distributor. I know how to wire it to get it running properly but I want to do this right. My concern is removing the wrong thing and losing my gages. Will removing the ecm affect them? Which coolant sensor needs to stay the one in the head or in the intake? Can I just remove all of the harness to the ecm? Any help or suggestions would be greatly appreciated.

 

Ok so I should have done a search before I asked any questions. sorry. But I still have a few questions even with all sensors disconected and wires removed will it hurt any thing to leave in the ecm? Will it still control the convertor lock-up and fuel pump?

 

Now don't everyone answer me at once. I know from the looks of things that this topic has been beat to death. But my problem is when I did a search the info I found was not consistent. One person said you don't need the ecm to control fuel pump and the next said you do need it. I would really be thankful for any clarity you can provide.

 

Your ECM will not control the lockup torque converter. Without the signals coming from the sensors and dizzy, it has no clue where your foot is and at what rpm the engine is at.

You'll need to get a vacuum controlled torque converter lockup switch kit - they range from $70 to $200 - they consist of a new 4th gear solenoid that gets installed in the tranny, a new wiring harness that gets installed in the tranny, a vacuum switch that gets connected to your carb, and optionally new wiring routed to the interior for toggle switches to lock T/C always or to unlock T/C always. You do not have to drop the tranny, but you do have to remove the pan, and thus lose all your fluid, for this procedure.

Good time to install the tranny pan drain plug, so this would be the last time you lose all the fluid on the driveway. Also a good time for a new tranny filter and o-ring, and a shift kit if you so desire.