47-55.1 What ac system fits best

[crushermechanic]

What ac system fits best under the dash of a 51? Do any of them come with the vent strip that mounts under the dash? Any with outside air for defrost?

[mr48chev]

Vintage Air and Old Air are two of the go to AC units with truck folks.

https://www.vintageair.com/

https://www.oldairproducts.com/

Both are in Texas ans both have been around for a number of years.

[crushermechanic]

Any experience with the old air system. I had a vintage air in my 71 and it was so so

[mr48chev]

No experience with Either personally. I've got a lot of friends who run Vintage Air in their street rods without an issue.

I've thought about just going old school on my 71 and running a Mark IV style under dash unit. It has a great heater so I really don't need heat/ac in it.

I don't have a stock dash in my 48 so the piece that hangs under the dash with vents doesn't work for me.

[e015475]

I just had the Old Air system installed on my '49 - don't know how well it works yet as it is still winter in AZ

Old Air gives you the option of vents through the center speaker grill, and Vintage Air has the plenum that mounts underneath the dash

I wanted my cab to look original, so I opted for the radio grill vents and the side vents tucked underneath the dash a little so they weren't very visible - I don't much care for the Vintage Air duct system under the dash.

I think the Old Air system packages up a little better than the Vintage Air system and there's less of it visible. My upholstery guy says he can pretty much make it disappear. Seems to have 3-4" of glovebox still available.

FWIW, the guy who installed the Old Air system says he's installed a lot of both brands and prefers the Old Air. When mine was in his shop, he had a couple installs there where he'd taken out the VA system and installed an OA

[e015475]

I don't believe either system has outside air capability - it is all recirc

[mick53]

I bought the Old Air inside kit but haven't installed it yet. I have an electric A/C compressor with remote condenser and Spal fan.

[dsraven]

a/c systems like to recirc the air because the way the system works best is with dry air, thats why there is a condensate drain on the evaporator. if you bring in fresh, outside air then the evap can get frozen with ice due to the warm air having a higher humidity level. if you want fresh air for the heater then you will likely need to find a system that also heats and has provisions for the fresh air intake. or, make your own provisions with a seperate heater. an a/c system with a heater core needs to have a door that controls the a/c side because, even though you might think it is weird, the a/c system is used to contro moisture in the air when the heater is on defrost.

[mick53]

Originally Posted by dsraven

a/c systems like to recirc the air because the way the system works best is with dry air, thats why there is a condensate drain on the evaporator. if you bring in fresh, outside air then the evap can get frozen with ice due to the warm air having a higher humidity level. if you want fresh air for the heater then you will likely need to find a system that also heats and has provisions for the fresh air intake. or, make your own provisions with a seperate heater. an a/c system with a heater core needs to have a door that controls the a/c side because, even though you might think it is weird, the a/c system is used to contro moisture in the air when the heater is on defrost.

Is it true that in modern cars the A/C comes on with the defrost?

[dsraven]

yes, true. it helps run some humid air through the a/c so the moisture, that usuallyy ends up condensing on the cold glass, gets caught up in the a/c system.
thats why the new cars have all those automatic electronic hvac doors that seem to take forever to move from heater to defrost. they are all timed etc.

[mr48chev]

I'm thinking that one could fab a plenum to route fresh air to an Old Air system. If that was wise or not, I am not sure.

Cost wise the complete all insclusive kits run pretty close to the same at around 1925.00

Old Air does seem to make it easier to spec out a "kit" that doesn't include the under dash plemum/control panel if yoy can't or don't want to use it. I'm planning on running the dash out of the first car I ever owned in my 48 (period correct) just because I like it and to mess with minds a bit but if you know that that car was, help keep the secret for the time being.
1625 or so complete with a polished compressor and 292 mount bracket.

The 1345.00 for the Old Air 47/53 inside package doesn't include compressor, bracket, condensor or hoses or dryer.

Another option is the Vintage Air Universal fit with a compressor bracket to match one's engine.

[crushermechanic]

Thanks for the info. I think I am going to go with the old air system

[e015475]

This is a center vent I built for my truck's AC. There's two stock plastic AC vents mounted onto an aluminum piece that fits in the dash.



Here's the aluminum panel that holds the vents-


The assembly ready to go into the dash-



I glued some steel rod on the grill so I could improve airflow a little bit



In the end, I didn't use it. Old Air had one that also had the AC controls that poked through the grill - I likeed the look of it so I bought theirs