Which AC compressor for r134 AC?

[Awann99]

I bought all the factory stuff I need to convert my heater truck to AC. I was going to go with vintage air but wanted to be able to pull in fresh air because the south is very humid.
Anyway. I think I have figured out most of the stuff I need to do a r134 conversion when I install everything. The only thing I am still up in the air about is the compressor. I was looking at an AC delco A6 compressor from rock auto. Would that work without pulling too much HP away from my engine? Is the sanden a better option? Any more options? I want to be able to stay the coolest and use as little HP as possible. I’m pulling 16.5 mpg at 70 with my 350/sm465 307 rear right now and would I like to not take it down too much by adding AC.
I also will usually drive the truck at 1300-1500 rpm in town. It just putts. I drive it like an old man (no offense to any old men). Would the A6 even work well at idle or low rpms?
Thank you.

[body bolt]

I drive like you do. I used a 4seasons aluminum A6 which works fine. Since I bought that thing I've heard some have had them fail. If I were to do it again I'd get a rebuilt GM/Delco/Harrison/Frigidaire. I used this condenser with the Vintage Air mount. I don't notice the HP loss and it gets plenty cold.

Originally Posted by Awann99

I bought[ all the factory stuff I need to convert my heater truck to AC. I was going to go with vintage air but wanted to be able to pull in fresh air because the south is very humid.
Anyway. I think I have figured out most of the stuff I need to do a r134 conversion when I install everything. The only thing I am still up in the air about is the compressor. I was looking at an AC delco A6 compressor from rock auto. Would that work without pulling too much HP away from my engine? Is the sanden a better option? Any more options? I want to be able to stay the coolest and use as little HP as possible. I’m pulling 16.5 mpg at 70 with my 350/sm465 307 rear right now and would I like to not take it down too much by adding AC.
I also will usually drive the truck at 1300-1500 rpm in town. It just putts. I drive it like an old man (no offense to any old men). Would the A6 even work well at idle or low rpms?
Thank you.

[Steeveedee]

I'd use the stock type A-6 compressor if the conversion uses a POA valve adjusted for 134. If you are going to a switch to cycle the compressor, use the R-4 compressor, because the A-6s don't suffer cycling gladly and fail fairly quickly, based on what I've seen over the years, here. You probably already know, but the oil for a 134 system is different.

[weq92f]

.

I run the A6. Next time it fails...I'm replacing it with a Sanden.

-klb

[Davidf]

Originally Posted by Steeveedee

I'd use the stock type A-6 compressor if the conversion uses a POA valve adjusted for 134. If you are going to a switch to cycle the compressor, use the R-4 compressor, because the A-6s don't suffer cycling gladly and fail fairly quickly, based on what I've seen over the years, here. You probably already know, but the oil for a 134 system is different.

+1 Factory a/c system, use the A6, otherwise go with Sanden.

[body bolt]

Yep, the clutches don't have the surface area to by cycled on and off.

Originally Posted by Steeveedee

I'd use the stock type A-6 compressor if the conversion uses a POA valve adjusted for 134. If you are going to a switch to cycle the compressor, use the R-4 compressor, because the A-6s don't suffer cycling gladly and fail fairly quickly, based on what I've seen over the years, here. You probably already know, but the oil for a 134 system is different.

[70cst]

Originally Posted by body bolt

I drive like you do. I used a 4seasons aluminum A6 which works fine. Since I bought that thing I've heard some have had them fail. If I were to do it again I'd get a rebuilt GM/Delco/Harrison/Frigidaire. I used this condenser with the Vintage Air mount. I don't notice the HP loss and it gets plenty cold.

Who sells the rebuilt GM/Delco/Harrison/Frigidaire Air Compressor (70-402BB) ...
Thanks

[body bolt]

ackits.com was where I bought mine but that was about 20 years ago. It lasted a little over 10 years when I assume the clutch failed as it still turns by hand.
`

Originally Posted by 70cst

Who sells the rebuilt GM/Delco/Harrison/Frigidaire Air Compressor (70-402BB) ...
Thanks

[leddzepp]

I use an A10, aluminum replacement for the A6. Factory AC in my 68. No leaks, no belt squealing, been working great for about 4 years now. I used R12 as original. I will never use an A6 again.

[body bolt]

Who made your compressor and the part number? When I bought mine a few years ago I understood I was buying an A10 but the manufacturer's description says it's an A6. Mine is a 4 Seasons 58098.

Originally Posted by leddzepp

I use an A10, aluminum replacement for the A6. Factory AC in my 68. No leaks, no belt squealing, been working great for about 4 years now. I used R12 as original. I will never use an A6 again.

[Davidf]

I have been the A6 aluminum replacement (four seasons) for years. Works fine. But, it came out with the engine to replaced with a LM7 LS engine...switching to R134a and using the Denso LS compressor. Going to try and sell the engine/700R4 as a package including the compressor.

[Steeveedee]

Originally Posted by Davidf

I have been the A6 aluminum replacement (four seasons) for years. Works fine. But, it came out with the engine to replaced with a LM7 LS engine...switching to R134a and using the Denso LS compressor. Going to try and sell the engine/700R4 as a package including the compressor.

What size engine?

[Davidf]

Originally Posted by Steeveedee

What size engine?

350. She's tired and fouls the #8 spark plug. But, no unusual noises, idles fine, and decently smooth when the plug is clean. I suspect bad valve stem seals. She is not a HP monster.

[leddzepp]

I don’t recall the manufacturer. I would imagine they all come from the same place, with each vendor putting their name on it. I bought an entire kit from autozone that included the compressor, drier/receiver, expansion valve, and a quart of mineral oil. They called it an A6 replacement but it’s an A10.

[body bolt]

So maybe mine is actually an A10. I'm using ester oil in case I didn't like the R134 result and opted to switch back to R12. With the POA properly adjusted R134 works just as well as R12. I love POA systems!

Originally Posted by leddzepp

I don’t recall the manufacturer. I would imagine they all come from the same place, with each vendor putting their name on it. I bought an entire kit from autozone that included the compressor, drier/receiver, expansion valve, and a quart of mineral oil. They called it an A6 replacement but it’s an A10.

[leddzepp]

I never had any luck with r134 in a factory AC system conversion, even adjusting the poa and other factors. If it works for you, great. I’m happy with r12. I have stockpiled both and use 134 in all of my newer cars that call for it.

[Big Kev-O]

Originally Posted by Awann99

I was going to go with vintage air but wanted to be able to pull in fresh air because the south is very humid.

"Fresh air" coming from a humid outdoor environment is loaded with moisture and latent heat. The best way to reduce the amount of moisture inside your cab is by recycling the air inside your cab. When air flows through your AC coil it cools off and the temperature falls below the dewpoint. When that happens water is pulled out of the air. Humid fresh air is much harder to cool than the air inside your cab which has already had a significant amount of moisture removed. So if you want a less humid environment inside your truck use a system can recycle the air inside the cab. This is why most modern cars automatically set the AC to recycle when on the max cool setting.

Having a system that lets you open & close the fresh air intake is the best option but max cooling & dehumidification is accomplished when the air is recycled.