I have eliminated the AC from my 72 El Camino but would still enjoy heat and defrost as winter is rapidly approaching. I am using the factory harness and notice that there is no direct hot lead from the blower motor to the switch in the dash. I realize that I could bipass the blower motor relay and wire directly to the fuse panel, but I would like to have more than one motor speeed for circulating air. Any clever ideas?

Let me check my info and get back to you...I think it's quite possible indeed.

<BLOCKQUOTE>quote:</font><HR>Originally posted by RobtW:
I have eliminated the AC from my 72 El Camino but would still enjoy heat and defrost as winter is rapidly approaching. I am using the factory harness and notice that there is no direct hot lead from the blower motor to the switch in the dash. I realize that I could bipass the blower motor relay and wire directly to the fuse panel, but I would like to have more than one motor speeed for circulating air. Any clever ideas?<HR></BLOCKQUOTE>

Okay I've been thinking about this, now not so sure http://www.chevelles.com/forum/frown.gif

Did you completely remove the evaporator box from under the hood? If so, there's no mounting place for the lo-speed resistor array. It originally bolted to the evap box. The non-a/c cars have their's mounted INSIDE the car, in the actual heating duct assembly. The air rushing past the wire-wound resistors aids in their cooling.

I don't have my car here to look at, (70 w/ A/C) so I'm not sure if the A/C cars also have provisions for non-a/c design, i.e. there's mounting place inside for the resistors and an un-used "heat only" harness that plugs into the resistors.

Don't try to wire anything into the fuse box without use of relays! That A/C blower motor draws more current than a non-A/C one, besides, it's a big load that shouldn't be "tapped" into the fusebox anyway.

<BLOCKQUOTE>quote:</font><HR>Originally posted by Coppertop:
Okay I've been thinking about this, now not so sure http://www.chevelles.com/forum/frown.gif

Did you completely remove the evaporator box from under the hood? If so, there's no mounting place for the lo-speed resistor array. It originally bolted to the evap box. The non-a/c cars have their's mounted INSIDE the car, in the actual heating duct assembly. The air rushing past the wire-wound resistors aids in their cooling.

I don't have my car here to look at, (70 w/ A/C) so I'm not sure if the A/C cars also have provisions for non-a/c design, i.e. there's mounting place inside for the resistors and an un-used "heat only" harness that plugs into the resistors.

Don't try to wire anything into the fuse box without use of relays! That A/C blower motor draws more current than a non-A/C one, besides, it's a big load that shouldn't be "tapped" into the fusebox anyway.<HR></BLOCKQUOTE>

I have removed the evaporator box and refabricated the profile of the AC unit. I wondered about the resistor you mentioned, but didn't know what it was called. I could see that the resistor is needed to complete the circuit becuase all of the leads from the switch itself gain their power from the blower motor relay. Without the resistor there is no circuit. I could salvage the resistor and relocate them into my fabricated unit, I guess. Since I am not using AC they would simply complete the circuit and otherwise be non-functional. This is probably the easiest solution since it just means drilling a half-dozen holes and plugging everything in. Thanks for your help, I'll give it a whirl.

RobtW, If you unplug the blower motor resistors you will still have 'HI' speed blower operation but only 'HI' speed. If you want the other lower speeds to operate it gets more complicated.

Louie Hammel

Robtw basically if you can mount the resistor package in the blower airstream of whatever you come up with in refabricating your heating system you will be fine. That way you will have all of your original blower speeds.