Having ditched the AC long ago, the first change was the AC delete heater box.
Now I'd like to swap out the vacuum assisted heater/defroster controls with those from a non AC car.
Is the swap straightforward? Do the heater ducts/air boxes/operators have to be replaced in order to work with the cable style dash controls?
Thanks in advance.

 

bump

 

As you know the 82-89 Non-AC cars used a cable set-up rather than vaccum to operate the air box doors. In order to convert from the vacuum AC system to the early cable Heater system the internal heater core box must be changed. The internal heater core box will match up to either a AC dash housing, or a non-AC dash housing ( or more accurately the dash vent boxes on it ) without a problem.

The 90-92 cars used a non-AC heater control that was vacuum operated ( unlike the early version.) This 90-92 vacuum operated non AC panel can be installed to make the conversion easier, but the control will have yellow letters and will "clash" with the white lettering on the rest of the interior. ( 90-92 non AC controllers are not cheap either ! )

The outside air vent boxes are usually omitted during this conversion because they require holes to be cut into the cowl and most do not wish to do that work.

I've got some non-AC stuff so if you decide to go ahead with your project and need anything, send me a PM.......

 

That's a fantastic bit of tech info. Thanks.
I have a donor I can strip right down to the under dash heater core box.
From what I gather from your post, that heater box and the cable operated dash controls will complete the conversion. (in an 86 Coupe w/now deleted AC)
Great stuff. Thanks again.

 

No Problem !

Since you've got access to a parts car,.... If your going in far enough to get the heater core box out than don't remove the cables that connect the heater core box to the controller. Just remove the center console and let the controller hang around till you get the heater core box out so there's little change of any little pieces breaking !

Good Luck !

 

Were there some cars that did not have the air vents in the cowls near the wipers?? Just curious.

 

How does the vacuum system work the heater? I think I might want to tear into this system next. Just doesn't heat like it used to.

 

All cars took incoming air from the cowl panel found under the wipers.

The non-AC cars had 2 outside air "vent" boxes; each was controlled by separate cable that mounted under the steering column. These air boxes were placed at each far corner of the firewall ( under the dash) and collected air from the firewall cowl, then delivered it to the passenger floor area. It was "forced" outside air and required no blower,....... just MPH ! These Vent boxes required a hole to be cut into the firewall cowl area.


Vacuum operates the AC heater system when the controller accepts engine vacuum and directs that vacuum to an air solenoid. ( There are several ) once vacuum is applied to a solenoid it would open/close a door inside the heater core box, & directing the air flow to the vents the controller is set to. ( Floor, Defrost, ect. )


Sounds like it's time for a new T-Stat !

 

T-stat on the engine or for the heater? I do have the ac on mine although it was long gone when I got it, want to go back one of these days. But I have the blower motor out right now as the old one stopped working. But even with it out the thing used to just heat like crazy with the fan on low or off but now I don't get much. Maybe I got a clog somewhere?