Should I bother with a stock a/c system (converted to 134a) in Texas?

[Dakota]

My Challenger was originally equipped with air conditioning.  The relatively mild summers in the Buffalo, NY area had reduced the urgency of getting the system running.  It was going to be one of my focus areas this spring, but now my wife and I have decided to move to Texas to be closer to family so the a/c work (and just about everything else in my life) has been put on hold until the relocation is behind us. The heater box, fan motor and RV-2 compressor have been repaired/restored and installed with provisions for using 134a refrigerant where changes were needed.  The remaining work primarily involves connecting all the lines and then doing the fun stuff like drying out and leak testing the system before charging it.   I believe I have all the parts and tools needed to finish the work with the stock system (yeah, I'm laughing at that "I don't have to buy anything else" fantasy too).

I'm curious what experience folks have had running the stock a/c system converted to 134a service in hot climates like Texas.   I know there are lighter, more efficient a/c compressors available from vendors like Bouchillon.   I have no heartburn moving away from stock components... I'd just rather not spend the money if it's not really necessary,  plus I've got a fair bit of sweat equity already invested in what I have.   

I'm too far down the road with the stock interior components to rip them out for something like a complete Vintage Air installation, so this is mostly a question around the compressor.

Care to share?  Thanks.

[Rich G.]

I converted the 73 to 134a with everything else original. Works ok but won't freeze you out. Stock blower motor isn't the most powerful thing.

[anlauto]

I was going to say the same thing...The stock stuff will work, but don't expect it to be as efficient as the system in your newer daily driver. 

[Dmod1974]

I don't think the Vintage Air blower motor is that strong either.  It makes a lot of noise and nowhere near the volume of air that you'd get from anything made since the 80's.  I recently replaced most of my crappy flexible duct that come with the aftermarket kits with some 90's and straight sections of rigid duct to increase flow.  The flex duct is corrugated and bulky which makes it very hard to route without getting crushed in spots or having really tight bends that kill flow.  It also doesn't secure very well to the vents or HVAC box either...  It helped for sure, but I think the blower motor and housing are still the limiting factor.

If the stock stuff works and gets cold enough, I think your money would be better spent elsewhere unless there is some other reason you need to change it out.

[Duodec]

Its been a long time since I researched this for my '71.   There were two issues I recall (presuming new components so its not a basic conversion): 

first, be very careful with the charge you install.  You cannot just use the same charge level as R12; I think its somewhat less.  You can't trust the sight glass; if it shows no bubbles then your system is probably overcharged. 

And systems designed for R134 had larger condenser capacity or efficiency for a given evaporator capacity.  So your stock condenser with stock airflow/fannage, etc is not releasing as much heat to the atmosphere with R134 (or else what it is releasing isn't enough for best R134 efficiency, don't recall).  So optionally try to increase condenser heat transfer via airflow, fannage, whatever... or use a more efficient condenser (heh! like to find that as a reproduction part!) which is a non-trivial exercise on an existing car and can impact engine cooling as well, depending on what you do. 

In any case you may never get the same reduction in air temperature that R12 provided.

And OBTW, a more powerful or efficient blower might very well reduce the effective interior air cooling as more air is pumped through the evaporator more quickly and doesn't give up as much heat; same concept as using a restrictor plate or thermostat in an engine so coolant doesn't flow through the radiator too quickly to give off enough of its heat.

I'm leaning towards keeping my car R-12 because I tucked away some back when it was available. Though I'm still considering a Sanden-style compressor since my RV2 needs to be replaced anyway.

[70vert]

Speaking of R12, I recently ran across 2 cans (from wayyyyy back, maybe 30 years ago). I no longer own an A/C car and wondering what the legalities are regarding them. Is it legal to sell, to ship, or even to own/use? I know home A/C required conversion and don't think its refrigerant is legal at all but maybe auto R12 has different rules.

Anyway, just 2 cans so not even sure why I've kept them. Hmm, maybe because I also don't know how to dispose of them   

[Dakota]

Is it legal to sell, to ship, or even to own/use? I know home A/C required conversion and don't think its refrigerant is legal at all but maybe auto R12 has different rules.

@70vert R12 is legal to use.   It was removed from new car systems between 1992-1994.  Production of new material stopped around 1996.   In the U.S., it can still be sold commercially to people and companies that have the proper EPA certification.   

There is a company called referigertfinders.com which purchases R12 inventories.   I have no experience with them... they're just someone that showed up in a Google search.

[Barracuda1]

You might want to look into HC12 if it is still available.  Another equivalent is R290.  It is compatible with the old R12 systems.  The difference is it is propane based.  I used this in a 1986 Dodge van I had and it worked great.
Years ago, it was frowned on being used in an automobile because in a crash, it could become flammable.  Yet today, they are using 1234yf, which operates at a higher pressure, and yes, it is flammable.

[Mopar5]

You can still get R-12 like it originally had its just expensive.

[Duodec]

I was prowling around to see if any of the auto parts places running 20% off & free shipping for Fathers Day had Challenger A/C condensers or evaporators available.  I didn't find any but ran across a site called original air (originalair.com) that has both reproduction and a higher efficiency unit available that they recommend for R-134a conversions:

"High performance parallel-flow a/c condenser for all 71 B-Body and 70-71 E-Body cars with factory air-conditioning. Installs exactly the same as the factory original."

I'm not familiar with the vendor, but a higher efficiency condenser is what you want to make up for at least part of the loss in efficiency incurred by converting to R-134a. 

[7212Mopar]

The original AC compressor that came with the car is a reciprocating piston type that use R12 refrigerant. Modern day AC compressor is mostly rotary scroll or vane type which are more efficient and use R134a refrigerant. R12 is very high in ozone depletion potential so it had been phased out since the 90. What is available to purchase is reclaimed stock as it is no longer manufactured. The original setup likely leak and R12 is not good for the environment. Not worth it as R12 is expensive to buy now. R134a has a very high global warming potential. It is phased out already in Europe and in progress here in the States but will be available for a long time. Retrofit market uses R134a compressor to stay legal to sell the equipment.