Advice on AC

[azmoparboy]

Hi everyone, lm a self taught car mechanic, but have been a aircraft mechanic for 40 plus years. What I do to my cars makes me happy. I have 2 Chryslers, 71 challenger and a 73 Charger. The 71 challenger has 134 in it while te 73 Charger has the old R12 system restored to factory. I live in Arizona and it gets hot here. Both systems work very well. The Charger looks just like factory and the Challenger I designed myself with sanden compressor. Everything under the hood is new, in the dash is restored old system. Now the Charger has real R12 that I purchased off of ebay and yes it is pricey. The compressor was completely restored, form crank to rod and pistons and oil pump with all new seals. This system works very nice. So do lots of homework, see what will work for you and build it. If you build it without a kit it will be cheaper, for me I love making from scratch. Here are some pictures of the Challenger just before I charged it with 134. I hope this encourages you.

Azmoparboy

 

[moparlee]

Hi everyone, lm a self taught car mechanic, but have been a aircraft mechanic for 40 plus years. What I do to my cars makes me happy. I have 2 Chryslers, 71 challenger and a 73 Charger. The 71 challenger has 134 in it while te 73 Charger has the old R12 system restored to factory. I live in Arizona and it gets hot here. Both systems work very well. The Charger looks just like factory and the Challenger I designed myself with sanden compressor. Everything under the hood is new, in the dash is restored old system. Now the Charger has real R12 that I purchased off of ebay and yes it is pricey. The compressor was completely restored, form crank to rod and pistons and oil pump with all new seals. This system works very nice. So do lots of homework, see what will work for you and build it. If you build it without a kit it will be cheaper, for me I love making from scratch. Here are some pictures of the Challenger just before I charged it with 134. I hope this encourages you.

Azmoparboy

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Nice work.

 

[ChallngeAccpted]

That's sort of backward of what you are thinking for some of the parts. Most parts stores do not have parts for 50 years old cars in stock, and need to go to specialty warehouses to get the parts if they will even make that effort for you. The Vintage Air, and other places use the Sanden compressor, which is used in many newer cars. Most condensers are by size, so fairly easy to get. Now the under dash parts would be specific the their manufacturers.

good point, I was referring to YearOne and classic industries for parts, but ideally a napa would be better. I have heard something about using an evaporator out of a new vehicle for our e bodies.

 

[ChallngeAccpted]

got ALL parts from NAPA except hoses--had original and sent to Vintage Auto Air for rebuild

Exactly what I wanted to do! thats awesome.

 

[ChallngeAccpted]

I do like the sound of that, but I just bought a brand new heater core. Cost $100 from rockauto. I definitely do not want to replace that lol

 

[ChallngeAccpted]

I do like the sound of that, but I just bought a brand new heater core. Cost $100 from rockauto. I definitely do not want to replace that lol

 

[ChallngeAccpted]

Hi everyone, lm a self taught car mechanic, but have been a aircraft mechanic for 40 plus years. What I do to my cars makes me happy. I have 2 Chryslers, 71 challenger and a 73 Charger. The 71 challenger has 134 in it while te 73 Charger has the old R12 system restored to factory. I live in Arizona and it gets hot here. Both systems work very well. The Charger looks just like factory and the Challenger I designed myself with sanden compressor. Everything under the hood is new, in the dash is restored old system. Now the Charger has real R12 that I purchased off of ebay and yes it is pricey. The compressor was completely restored, form crank to rod and pistons and oil pump with all new seals. This system works very nice. So do lots of homework, see what will work for you and build it. If you build it without a kit it will be cheaper, for me I love making from scratch. Here are some pictures of the Challenger just before I charged it with 134. I hope this encourages you.

Azmoparboy

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That looks nice! do you happen to have a parts list from when you did it?

 

[azmoparboy]

Scratch Build Auto AC System

However chooses to build their own AC system can alter as many things as you wish, I came up with mine this way.

I extracted the hard piece of tubing from the suction hose just off of the expansion coils at the firewall. To me this only made sense to use this piece to install the expansion valve. Use a expansion valve # 38844. I used an adapter to reduce that piece of tubing from a size 10 to a size 8 that will connect to the compressor. This piece of tubing is where I installed the system cycling switch. You can also install it inside the heater/AC box inside the car just aft of the expansion coils. Your system will need this switch, believe me, this system will work so good it will freeze the expansion coils up and no air will flow into the cabin of your car. There are different types of cycling switches with adjustable settings as well as per set temperatures. I’ve posted pictures, see pics.

I purchased a hose kit off of eBay that had all 3 sizes of hose that would be needed to construct the system. It came with o-rings, Binary switch, and drier. If you choose, you can use all hose for the system but I chose to use some hard lines on my system, I just like the likes of hard lines. Hard lines can also be purchased from eBay, summit racing, or jeg’s in different sizes and end combinations to install to you liking. Now if you’ve never formed hard lines this may not be a choice for your system.

Again I used eBay to acquire the condenser, CNFP16 x 24. I attached it to the radiator from support with small “L” brackets, use your creative ability to make it look good to you.

Now for the compressor. You can use any brand you wish. I’ve chosen to purchase a Genuine Sanden compressor # 508. The prices very a lot so this is one of the ways to really cut down on the expense of the system. Also take into consideration your belt drive system of your engine, either V-belt or serpentine belt, that makes a big difference but not on the price.

There are many different styles of compressor mounts that fit on small block, big block, relocating the compressor to a lower position to hide it from view, you will be designing your system the way you would like it to look. I used the existing single wire that comes off of the bulkhead to make a complete lope through the cycling switch to the Binary switch and then connect to the compressor, this will power the compressor clutch and energize the system.

Here are some pictures of my system up close so you can see what I’ve created. Ask questions if you need.

 

[ChallngeAccpted]

Great write up! that is a damn nice looking system! what did you use for your evaporator? I am planning on pulling my dash out so I can knock everything out at once, I plan to rebuild my heater and AC boxes, replace my heater core and evaporator, and my dash pad. And if we have the original hard lines, can we use them?

 

[lemondana]

Keep in mind, that R134a is being phased out as of right now. R12 is still legal to use. There is always some around somewhere-swap meets, garage sales, house auctions. So many people have been brainwashed into thinking that R134a is their only alternative. It is not! Find and use R12, you won't be sorry. Back in 1977 I had a 67 Coronet with factory AC, It was the coldest AC that I have ever encountered. It would blow frost off of the metal vents in the dash. People in the backseat would ask me to turn it down-it was too cold!
There was a guy over on FABO a couple weeks ago that talking about the Mopar V type compressor, it is, in reality very efficient, it is 10.something cubic inches and the Sanden is only 8 cubic inches. After reading his write-up, I'll be keeping my big ole V type.

 

[NoCar340]

The RV2 compressor is effective, but it is not efficient. It imparts a much larger parasitic drag on the engine than an axial compressor like a Sanden. It also sounds like your upstairs neighbor is listening to German industrial dance music... it wasn't widely known as "The Thumper" without good reason. It does work exceptionally well, though. My '79 300's AC was definitely sufficient, but my '77 Cordoba would freeze you out of the car. Same basic system; the only real difference was the compressor: The '79 was axial, '77 was an RV2. 'Course, the T-tops were out of the 300 most nice days anyhow.

Fun side note: A friend and former co-worker disconnected the factory AC in his '76 Power Wagon but left the compressor in place. He ran an intake pipe to a filter, the outlet pipe to a tank in the bed, and used a Hobbs switch to engage/disengage the clutch. Manually engage the fast-idle cam, switch the factory heater control to AC, and boom--air compressor. He had an off-road race truck at the time and that was their pit compressor, built right into their tow rig. Not as effective as a shop compressor, but much better than any Craftsman oil-less portable unit.

R12 is a better refrigerant than R134, without question. That being said, the OE E-body evaporator core is freakin' huge. There's a ton of surface area there, so I would expect the AC to work well with R12, R134, R1234YF, propane, unicorn farts or any other compressible gas with reasonable thermal properties to work just fine. Of course, if your replacement evaporator is aluminum instead of copper/brass, you'll give up some performance there as well. Aluminum is a much worse thermal conductor than copper/brass. I think I got my replacement copper/brass unit from Original Air Group. They still show it available. I bought a heater core from RockAuto around the same time, and was pleasantly surprised to receive a copper/brass unit there, too. Rock has nothing available but non-AC now; I suspect the AC one may have finally gone dodo in the replacement world. If they come back, they'll probably be either aluminum... or very expensive.

 

[ChallngeAccpted]

The RV2 compressor is effective, but it is not efficient. It imparts a much larger parasitic drag on the engine than an axial compressor like a Sanden. It also sounds like your upstairs neighbor is listening to German industrial dance music... it wasn't widely known as "The Thumper" without good reason. It does work exceptionally well, though. My '79 300's AC was definitely sufficient, but my '77 Cordoba would freeze you out of the car. Same basic system; the only real difference was the compressor: The '79 was axial, '77 was an RV2. 'Course, the T-tops were out of the 300 most nice days anyhow.

Fun side note: A friend and former co-worker disconnected the factory AC in his '76 Power Wagon but left the compressor in place. He ran an intake pipe to a filter, the outlet pipe to a tank in the bed, and used a Hobbs switch to engage/disengage the clutch. Manually engage the fast-idle cam, switch the factory heater control to AC, and boom--air compressor. He had an off-road race truck at the time and that was their pit compressor, built right into their tow rig. Not as effective as a shop compressor, but much better than any Craftsman oil-less portable unit.

R12 is a better refrigerant than R134, without question. That being said, the OE E-body evaporator core is freakin' huge. There's a ton of surface area there, so I would expect the AC to work well with R12, R134, R1234YF, propane, unicorn farts or any other compressible gas with reasonable thermal properties to work just fine. Of course, if your replacement evaporator is aluminum instead of copper/brass, you'll give up some performance there as well. Aluminum is a much worse thermal conductor than copper/brass. I think I got my replacement copper/brass unit from Original Air Group. They still show it available. I bought a heater core from RockAuto around the same time, and was pleasantly surprised to receive a copper/brass unit there, too. Rock has nothing available but non-AC now; I suspect the AC one may have finally gone dodo in the replacement world. If they come back, they'll probably be either aluminum... or very expensive.

I ordered my heater core from rock auto and mine is brass. I was waiting to tear the dash apart until I find what evaporator to use. ANyone get their original one re cored?

 

[NoCar340]

I'm no HVAC/radiator guy, but I don't think it actually can be re-cored:

 

[azmoparboy]

Hi Evan, I used the old evaporator, and coolants go, R12 is sill around and I don’t think that the 134 will disappear any time soon. Do a search on eBay for real R12, it’s out there, I just bought a case of real R12 and if your really want a lot of R 12 there are 35lbs bottles out there as well. This photo is off eBay.