FYI FORD MustangSteve's Ford Mustang Forum / Help on A/C. What would be better stock or aftermarket?

**Posted by True74yamaha** 5/04/2024 7:41 PM

1965 ford Mustang. I was curious what would be better my car had factory A/C. Should I keep factory as I love and prefer looks of original A/C floor unit. Should I keep factory A/C how would I get the A/C charged? If dont keep Factory A/C if aftermarket is better way to go. What do I have to do with the factory fresh air cowl vents in Cowl? I was curious If I need to remove both cowl vents or if I need to remove my passenger side cowl vent and that's all?

**Posted by RTM** 5/05/2024 5:07 AM

I have zero experience with factory AC in a vintage mustang. I’m currently installing the CAA AC setup in my 66 project. This kit provides a plate to block off the fresh air vent on the passenger side.

The old system if kept would have to converted to modern Freon. I’m not sure how efficient the system is when converted. I’ve always read mixed reviews on how well the conversion would work. The CAA kit I have claims to be an improvement over their previous kit.

If I had zero AC parts to start with, then I would go aftermarket for sure.

**Posted by John Ha** 5/05/2024 6:10 AM

If you have the complete original system you can try to find someone who still works with R12. It may be a long search and will certainly be expensive if you do find someone.

You can use all of the parts of the original system with R134 but you'll need to flush the entire system, change the compressor oil to something compatible with R134, and replace the dryer.

**Posted by BobE** 5/05/2024 8:00 AM

John Ha wrote:
If you have the complete original system you can try to find someone who still works with R12. It may be a long search and will certainly be expensive if you do find someone.

You can use all of the parts of the original system with R134 but you'll need to flush the entire system, change the compressor oil to something compatible with R134, and replace the dryer.

I changed from R12 to R134 in my 86 Bronco. While the R134 did cool the interior, it didn't cool as well as with R12. The system components are different between the two, and other components need to be changed to take full advantage of switching to R134.

**Posted by rpm** 5/05/2024 9:17 AM

R12 is still available, ya it costs more but cools better. The only thing different is the size of the Schrader valve fittings. It ain't rocket science to evacuate and charge the system. If I can do it, anyone can. True story.

**Posted by MS** **Online!** 5/06/2024 8:51 AM

On my 65 convertible, I plan to keep the original underdash unit and install a sanden compressor with a Vintage Air condenser and convert to R134a.

The disadvantage of this system is that the defroster does not have refrigerated air like a complete Vintage Air in-dash system like in my 66. Since the vert is a fair weather driver, I figure that won’t be an issue.

In the 66, where it is driven on long trips, rain or shine, it is imperative to have a good working defrost system.

**Posted by True74yamaha** 5/06/2024 9:53 AM

Thank you for the replies I think I'll keep my stock under dash unit and see how it works. I guess that means either new cowl bottom or two repair panels. My cowl in perfect shape except the Flats around where the hats mount lightly pitted may sand blast off. Needed to figure out which way to go with the A/C so I knew If I should keep my fresh air vents. To any of you think I should remove the cowl fresh air vents?

**Posted by Rudi** 5/06/2024 11:30 AM

Rain x anti fog.

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**Posted by John Ha** 5/06/2024 12:56 PM

True74yamaha wrote:
Thank you for the replies I think I'll keep my stock under dash unit and see how it works. ... To any of you think I should remove the cowl fresh air vents?

Why not keep them? You won't always need to run the AC. And having a fresh air source without opening the windows is nice sometimes.

As for defrosting, you can set the heat on high and channel it through the defroster ducting when you need to defrost the windshield. Hot air tends to absorb moisture.

Later model cars run air conditioned air through the defrost vents because that air is dried during the cooling process (hence the need for the condensate water drain).

**Posted by True74yamaha** 5/06/2024 1:01 PM

Cool I think I shall keep my cowl fresh air vents. I'm still planning on keeping the vents in the cowl. So they might as well do what they were intended to do.

**Posted by BobE** 5/07/2024 7:50 AM

The Vintage A/C system eliminates the passenger side vent. Vintage supplies a cap to block off the driver's side vent, bit it doesn't have to be used. However, leaving this vent, I believe, would complicate the routing of the A/C ducts to the drivers side. I eliminated both OEM vents on my install.
What I found difficult in installing the Vintage system was the routing of the duct tubes for the A/C and defrost. It gets pretty tight under the 65/66 dash.