well call me a puss but its hot! i want to install the factory air from a 72 elk into my 70 SS coupe. will the engine bay harness need to be modified? or replaced with the 72 harness? also what about the underdash harness? thanks

I did this a long time ago. All you need is the complete harnesses from the A/C system. They are totally separate from the cars wiring. As lng as ALL the A/C stuff is from the same year car you should be OK. There are differences within the various year A/C systems so using a 72 A/C wiring harness with a 71 A/C system can be a bit of a PIA. Transplanting the entire 72 A/C system into a 70 should not be hard. Make sure you have the correct compressor. Some where along the line they added something called a superheat switch to the compressor. One little wire is required to plug into the Super Heat Switch and that wire is only on the harness for the year they offered the Super Heat. If i recall it was a mid year addition so some cars had it some did not. Can't recall what year but as I said stay with a complete A/C system for any given year and it should go right in.

Also when I say "complete system" you gotta make sure you get the kick panels from the donor car they are different on A/C and Non Ac cars.

thanks oman! i have a 72 elk i traded for and cant get a title so the air complete will be used from it. there are a couple at the salvage yards for a 70 malibu would they be better to install? again thanks !

I dont think there is much differrence but if I had a chice I would go with the later systems there are little changes and I guess they represent changes that The General decided were worthwhile.

The sysrems with the Super Heat Switch are better ...if the compressor head pressure gets too high the switch signals the A/C clutch to take a "time out" till things calm down. Not sure what would cause the head pressure to be too high but the "Safety valve " provided by that little switch is a good thing to have.

The Super heat switch is in the back of the compressor back where the hoses attach. It is a tiny little thing about the diameter of a dime, might be smaller even. It has a single pin terminal and one wire that plugs onto the pin.

Another consideration, not reason to change from one year to another as far as what you select for a donor system. Take all the ducting you can lay your hands on. Everything every last piece INCLUDING the back sides of the dash outlets. I am not sure what year astro ventilation showed up...it was in a non A/C 72 that I have. You might find some inconsistencies in the recipient car IF you are crossing parts from a non astro vent car to an astro vent car or vice versa. Keep all the ducts and dont let the wreckin yard sell what they have till you are done with you install.

Last tip get the valve / flapper door that sits up in the cowl in front of the windshield. It is easy to overlook and without it you ducting will not be right when you select MAX Air. That door closes to allow the sys. to recirculate inside air and opens to allow inside and outside air to mix.

well call me a puss but its hot! i want to install the factory air from a 72 elk into my 70 SS coupe. will the engine bay harness need to be modified? or replaced with the 72 harness? also what about the underdash harness? thanks Is the 70 SS originally a non A/C car?
There is a difference in the firewalls between an A/C car and a non A/C car.
One 4" hole through on each side difference.

Is the 70 SS originally a non A/C car?
There is a difference in the firewalls between an A/C car and a non A/C car.
One 4" hole through on each side difference.

The firewall is VERY easy to adjust if the recipient car was not an A/C car. For those that are interested look in the archives for some of my posts. If you are actually doing one of these I could take the time to draw up a template that will tell ya exactly What you need to do And exactly where you need to do it to accomodate the differences. The fix can be done WITHOUT any welding and the repair is nearly invisible if you are handy at shaping sheet metal.