Vintage Mustang Forums banner

1 - 13 of 13 Posts

·
Registered
Joined
·
135 Posts
Discussion Starter #1
Looking into piecing together a basic underdash A/C system for my 68 coupe using a Mark IV type evaporator. Vintage Air has a nice reproduction unit that Summit has for $300. There are also many cheaper underdash evaporators on the market.
I don't think the "Sure Fit" A/C kits on the market are the best choice, although easiest, since I have a Fox body serpentine system and the desire to have custom hose routing. Found Eaton Aeroquip EZ Clip AC Air Conditioning System, seems easy to make custom hoses but I may want to use hard lines from condenser to drier and bulkhead fittings to get through radiator suppor . Read somewhere to use the largest condenser possible. What is the largest that could fit in a 68? Any advice how to proceed?

Thanks for the help,
Joseph
 

·
Just some guy
67 coupe, 69 Sportsroof, 86 hatchback
Joined
·
20,853 Posts
Just out of curiosity I wonder why you want to use an underdash over going with a factory style in-dash setup. One of nicer things about in-dash AC is that you can use it to defog your windshield. Which you cannot do with an underdash.
On my '67 I chose to source a combination of new and used stock type parts for the in dash AC where underhood will be completely aftermarket/custom. When I get to that part of the install. The interior is done.
 

·
Premium Member
Joined
·
12,345 Posts
I bought a Vintage Air evaporator kit for my '65 and then I bought my compressor, condenser and filter/drier separately because of my custom installation. I bought hose and fittings and then borrowed a crimping tool to make the hoses.
 

·
Registered
Joined
·
1,991 Posts
If you're doing a custom setup, you can use reduced diameter hose for the soft lines. It's smaller than the standard size hose and makes tighter bends. It used smaller crimp fittings too, so don't change your mind after you buy all the regular sized fittings (like I did).

Here's the size difference for the larger hose.


I plumbed my stuff to go through the inner fender on the passenger side.
 

·
Registered
Joined
·
5,528 Posts
Don't know about "largest." If that is true it must be about best efficiency which is a nice thing but then there is also things like "more than you'll ever use, impressive, pretty good, more than adequate and good enough for me." I can't imagine a few square inches or even a dozen is going to amount to enough to really worry about. I'v been meaning to measure out my original evaporator so as to use the smallest condenser within reason.
I do know that they should be matched within a ratio to the evaporator. I also know that if the condenser is too large your evaporator will produce damp to moist air ( likely not a problem in a car but will mold up your house).

the only useful thing i got for you is to check out 65'6 condensers and see how the drier is hard lined directly to it. Clean and compact, no extra lines needed:)
 

·
Registered
Joined
·
135 Posts
Discussion Starter #6
Thanks for the replies.
Wanting to use an underdash because the heater/defrost works fine (new heater core) and ease of install and cost. I gather a complete functioning underdash will set me back around $800-$900 installed, charged, blowing cold air.
Good tip on use of reduced hose. Curious if it has the longevity of regular hose, there is a considerable difference in wall thickness. Will get a hose kit with extra long hose in case I decide on longer than normal run.
Will match the condenser to system size. Guess bigger is not better in this case. And will try to find the drier mounted to condenser.
 

·
Registered
Joined
·
5,528 Posts
Thanks for the replies.
Wanting to use an underdash because the heater/defrost works fine (new heater core) and ease of install and cost. I gather a complete functioning underdash will set me back around $800-$900 installed, charged, blowing cold air.
Good tip on use of reduced hose. Curious if it has the longevity of regular hose, there is a considerable difference in wall thickness. Will get a hose kit with extra long hose in case I decide on longer than normal run.
Will match the condenser to system size. Guess bigger is not better in this case. And will try to find the drier mounted to condenser.
Been reading up again myself since I want to get mine together before next summer and try not to completely block the rad if i can.
Informative I guess, they are in the bigger the better and get the biggest you can camp.
they have interesting DIY options as far as parts and pieces. One thing i found is they have many different sizes of condensers to match with a single sized under dash evaporator so maybe its not all that critical in a car system but I did find that too big a cond might make your evap freeze up but that can be solved with a different expansion valve, soooo....
Lots more info about home ACs to be found, but they just mention tonnage. I couldnt find a real physical measurement to size the two pieces together. It was mentioned that using a somewhat under sized cond. is a way to slightly up cheat on efficiency for a higher SEER.
 

·
Just some guy
67 coupe, 69 Sportsroof, 86 hatchback
Joined
·
20,853 Posts
Since you can buy a direct bolt-in OEM style condenser or the larger capacity OEM style from NPD if you plan to run R134A I don't see why one would feel they had to reinvent the wheel. Either could be used with an underdash unit. The evaporators in those (that I've seen) appear to be roughly the same size overall as the in-dash condenser.
 

·
Registered
Joined
·
135 Posts
Discussion Starter #9
Thanks for the articles 1ofAMillion, the HotRod one is informative. Since I am not interested in keeping stock appearance no need to spend the higher prices from NPD. Not trying to reinvent the wheel per se just get the A/C job done with budget in mind. I think Nostalgic AC has all necessary parts for around $800. Need to ask if they can provide a DIY "reduced" hose kit, if so will order up.
 

·
Registered
Joined
·
1,991 Posts
I read about the reduced diameter hose on another forum. Didn’t find any ready to install kits (plus i was doing custom touting so that wouldn’t have helped at all. So I went to a local hydraulic hose shop and bought the different sized hoses and fittings.

I estimated how long the hoses needed to be and then rounded up.

When I had it all cut to size and the fittings indexed to the hoses (and marked) I brought them back and they crimped the fittings.


Sent from my iPhone using Tapatalk
 
  • Like
Reactions: 1ofAMillion+

·
Just some guy
67 coupe, 69 Sportsroof, 86 hatchback
Joined
·
20,853 Posts
I installed factory air in my non-AC '67 via some parts I found on Craigslist and a swap meet. Freshened up with some new parts from NPD. I still have to get hoses, a condenser, and a compressor bracket (if I don't make my own). So far I have right at $300 in it. I don't believe I'd like to invest three times that much in system that won't defog my windshield but that's just me. "Budget" means different things to different people.

Year before last I bought most of the factory in-dash AC bit to convert my '69 at a swap meet for $125. Patience often pays off.
 
  • Like
Reactions: rpm

·
Registered
Joined
·
135 Posts
Discussion Starter #12
I hear you on the swap meet stuff getting er done the most cost effective manner. I live in a rural part of CA so there are no swap meets within a reasonable driving distance, kinda stuck local parts stores or mail ordering parts. If the underdash unit can fit with the existing functioning heater core and defrost ducting then it's a win for me.
 

·
Just some guy
67 coupe, 69 Sportsroof, 86 hatchback
Joined
·
20,853 Posts
"If the underdash unit can fit with the existing functioning heater core and defrost ducting" Kind of the point, that'd be a "no" on the defrost ducting. An underdash is like hanging a hair dryer under the dash that blows cool air instead of warm. It's not integrated with anything.
That said, if you already HAVE the thing, using it is more sensible than tossing it in favor of stuff you don't have and don't know if you can find. Plus the fact that they work just fine strictly as an AC to make your car more comfortable.
I never personally liked how they just look "tacked on" basically.
 
  • Like
Reactions: Redneckgearhead
1 - 13 of 13 Posts
Top