Adding a/c to a non-a/c Hornet

I am interested in adding a/c to a '77 6 cyl Hornet. Can anyone who has been through this give me some advise? Thought about buying an aftermarket setup or buying parts and pieces from a doner car. The later would keep it more "original" but function over appearence is what counts. The car does have a non a/c package tray.

Rather than use an original type compressor I suggest you get the original bracket then get an adapter for a Sanden compressor. They are much smaller and take much less power than the old York compressors. Any AC shop or aftermarket AC vendor (such as Vintage Air) will have them.

If you can find everything you need locally in a donor car you're doing good! Most of the stuff from an Eagle or Concord will work as well... ducting in the dash may be slightly different but the main HVAC box will interchange. If you don't have a local donor I'd consider something from Vintage Air or Southern Air. The universal hot-rod units aren't too hard to install.

Yall are so right regarding York  vs Sanden.  I love the York for its sump oiling and tuffness, but dangit , it is a hp buzzkill.  One thing worth noting, AMC was the only company I know of that, in the day, cycled their compressors instead of having them run all the time and using a blending of air to control temp. 

I've got a 4.0L Sanden compressor, Chrysler LS parallel flow condenser, stock 63 AMC evaporator and housing (including the original expansion valve), and a generic drier. Had to have hoses made to mate the o-ring compressor and condenser to the flare fitting evaporator, but that wasn't any more expensive than replacing the old original hoses would have been. I managed to salvage the original flare ends and reused them, just had to have new collars on them. Be careful cutting the old collar and hose off and the ends on any of the hoses can be reused, but I wouldn't unless new aren't available or are hard to find.

I have blending problems using the old evap housing. The flaps and such don't seal good and are a bit stiff, and the 63 version doesn't distribute heat very well. I'm thinking about spending the $250-300 for a new style aftermarket evap/heat unit. Then I can just seal the hole in the cowl floor where the heater was. The aftermarket systems all recirculate inside air and don't draw in fresh air. I've got the kick panel vents for fresh air anyway, can blend a bit if I need to. Those old cars will never be as tightly sealed as new ones though!

I might just seal part of the heat outlet -- 70% or so gets dumped on the passenger so in the winter the passenger is toasty or hot while the driver is a bit on the cool side.  The only problem with this idea is the big heat outlet becomes the big AC inlet when AC is on! Recirculates AC all the time, only brings in fresh air for heating. The Hornet and later systems work better. I've even considered see if I could mount a Hornet or newer big AMC box in the 63, but I think the vent locations might be an issue.


Edited by farna - Jan/10/2012 at 11:08am

I totally agree! You will need to pull the old heater housing out to do a good aftermarket system. I don't think the dash needs to come out, just pull the glove box door and the glove box itself and you should be able to get to everything. Cover the hole in the cowl floor where the original heat intake was. A piece of sheet metal with about a 1/2" overlap all around will work fine. Silicone around the opening then push the sheet metal up and screw it on. I suggest you drill the screw holes (or use self-drilling screws) and fit the panel THEN pull it off, add silicone sealer, and put back in place.

Vintage Air is a good place to go, but Southern Air (http://www.southernrods.com/categories/a-c-and-heat-units-and-kits-southern-air-1.html) has good units as well. Their Maxi Cooler I/II/IIIkits are good, and run $800-$830 for everything. You don't need a compressor bracket though. The Superfrost Pro is the best deal, $700 for a kit. Call and ask if they will provide a York to Sanden compressor adapter instead of a bracket, then use a factory AMC engine bracket. That won't be too hard to find Do the same if ordering a Vintage Air kit. 

You might be able to get by with retaining the heater and using something like the Southern Air Trimline or Econo Cooler under dash kit by removing the package shelf. Those run $650 with everything.

Now you could get some junkyard parts and just the inside unit. Inside units run just a bit more than half the kit price. They include everything but the compressor, bracket, and condenser. You can score a good condenser from a salvage yard easy enough. You could also save a bit on a compressor, but get the newest one you can find. My 88 compressor gave up a few years ago -- would hold a charge for a couple months if used much over the summer starting about three years ago. I'm going to replace it with a 99 model I just happened to pick up with some other parts. Won't know if it's good until installed and the system is charged though. That just a risk with a used compressor! New compressor alone is around $300, so if you want a new compressor get the kit and use the new condenser too -- even if they don't swap the bracket for an adapter or give you a credit for not taking the bracket. You can find York to Sanden adapters on the 'net for $39.99 all day.


Edited by farna - Jan/11/2012 at 12:04pm