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Discussion Starter #1
I imagine this is fairly common.

My main question is what do you do with the fresh air vents? I like having them, but don't know if I can leave them on the car. I know the ac cars don't have them, but is that for a real reason like they interfere with something on the ac?

Thanks,
Russ
 

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Hey Russ,

My 69 had factory air but I replaced that system with an aftermarket unit from Classic Auto Air for a couple of reasons. I was going to have to replace some of my factory components (compressor, etc.), after researching the topic it appeared that those units only work so-so when converted from R12 to R134, and lastly the cam I'm running doesn't make enough vacuum to run all the doors and valves on the factory system reliably.

If you want to go the same route, you can keep your kick panel fresh air vents and have the best of both worlds.

If you go the factory unit, it has it's own mechanisms for venting in outside air without having the a/c running --- so you can have fresh air vents either way.


Bear
 

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It is fairly common to install aftermarket AC in a non AC car, and much less common to convert a non AC car to factory AC. It is a TON of work. Not only that, factory AC is heavy, bulky, intrusive on the engine compartment, and does not cool as well as the new technology aftermarket stuff, which is more compact, more efficient, and a whole lot easier to install. I spoke with an original owner of a '65 GTO with factory AC, and he said it was only good for days under 100. When he switched to Vintage Air, it cooled far better on 102-115 days, and we have a bunch of those out here each summer. If your car is non factory AC, I would install a Vintage Air type of system and be done with it. The value of the vehicle would probably be higher, too.
 

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can be done, but firewall has to be cut in several places, to add evaporator box and inside heater box. Factory system was good when it is sealed properly.
 

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Discussion Starter #5
Well, it always comes down to money.

I have a good part of the dash and firewall stuff. Already have an ac dash with controls, and the big firewall box with components that mounts on the firewall. I would prefer not to use a stock compressor, would like to go with one setup for R134. But some cooling is better than none.

If the money situation changes then I would love to go with Vintage Air or something.

Oh, not worried about the value of the car. Most people will think it is worthless when I am done. One piece fiberglass tilt front end, custom by me wiring harness with fuse box in trunk with battery, 97 Explorer bucket seats, 700R4 trans, no back seat at all, roll bar in future, etc. :)


Thanks,
Russ
 

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Hey Russ...
Having done some research on the topic, the problem with converting from R12 to R134a doesn't have anything to do with the compressor. As long as you start with a clean and dry system, the compressor doesn't know or care what kind of gas it's squeezing. The problem is with the part that allows the compressed gas (liguid) to evaporate into a gass and get cold. This was usually something called a POA valve on the factory systems. That's where the calibration is that "cares" about what kind of refrigerant it's dealing with. Problem is, you can't get them anymore - for R12 or R134a - or if you do find one it's hideously expensive and will need to be recalibrated for R134a. There are things called "POA elimination kits" that replace that component with the more modern orifice tube setup, but I've heard that they really don't work very well (despite being promoted by lots of sites that sell them).

If you're going to run that system, it's best to just go ahead and run it with R12 the way it was originally designed - assuming your POA valve and all the other components that "see" gas are in good working order, don't leak, haven't rusted, etc. It's still possible to purchase R12 and deal with it yourself, but you do have to be "licensed" to do so. When I was looking into doing that myself I found several internet sites where one could take the necessary training and get certified for the license. It didn't look too bad to do.

I still had 100% of all my original factory air components (and still do), but when I started looking at what it was going to cost for a new compressor (mine's bad), all the other components that needed replacing (including the POA valve if I could find one) it turned out it was going to be more expensive than just replacing the whole system --- and I'd still have the vacuum problem due to the cam.

Your situation might be different though and I don't want to talk you into something that's not a good idea for you - I'm just encouraging you to do your homework and figure out what it's really going to cost you to get the factory system going.

Timely topic :) I just got done a few minutes ago evacuating and charging my new Classic Auto Air system for the first time, and it's working great. I've got a "cool" car now :) I went through quite a lot to adapt the Chevelle kit (no one makes a turn key kit yet for the 69 GTO - 67 and earlier yes, but not the 69) to my car and retain as much as possible all the original factory controls - but I did it. Holler if I can help in some way.

Bear
 

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Discussion Starter #7
Thanks.
I read your posts on that conversion. Good stuff.
I am thinking that I will be piecing this thing together for the most part. Out of the big bucks to go buy things like a whole ac, or engine, or etc.
Don't know what shape the ac stuff I have is in. Only paid like $20 or was it $40 for the firewall stuff at Norwalk. Not thrilled about the size either, my 70 GTO had non working air (this was when I lived in Phoenix and it was my dd) so I know what to expect there. Speaking of which, good timing on getting the ac working. :rofl:

Might be moot. Haven't had good luck finishing a project lately. Hoping this one goes better, not going to be moving in the middle of it since we bought the current place.

Russ
 

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Discussion Starter #8
Oh, speaking of that conversion, would it have been easier if you didn't want to keep the factory controls?
As many changes as I am making that isn't an issue for me. One thing I am doing is going to be filling in all the holes in the dash. Will be moving the switches, most likely to an overhead console. Something I have always wanted to do with a car. :)
Obviously I am not worried about keeping it stock looking.
Thanks,
Russ
 

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Yes, if I hadn't been so anal about wanting to make it look and work as close to "original" as possible it would have been MUCH easier. Even with all that work I still had to give some things up, most notably any modes that use outside air. Everything about the aftermarket unit always runs in re-circulate mode, processing the air that's already inside the car regardless of whether it's heating or cooling. That's the one trait I'm not so thrilled about. There might be some hope though. I bought some replacement kick panels with stereo speakers built in, and not being sure how everything would fit I took a chance and ordered the ones designed for cars without a/c. Turns out they have manually operated doors that, if I remove the block off plates and install them, will allow an outside vent capability - as long as you don't mind reaching down, opening the latch, and opening the door. :)


As far as the pieces you have -- I've been told a lot depends on climate, but if the components that "see" gas (compressor, condenser, evaporator, hoses, receiver/dryer/accumulator, etc.) have been open to the atmosphere for any length of time they're probably toast. The more humid the climate, the more likely that is - or so I've been told.
 

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Bear, as usual, a great condensed explanation on the AC system, and yes, receiver-dryers /accumulators are a throw-away item (like an oil filter) and there may be some issues with other components that have been open to atmosphere, like compressors. Hoses, evaporators, and condensers can sometimes be flushed out, blown out with air and installed successfully if not too grungy....and if the system is evacuated for a long enough time. Here in dry CA, with humidity very low, parts tend not to get corroded and can be "made to work" often. I've been back to the mid-west, south, and east coast, and I noticed a lot more corrosion on all things old and metal.
 
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