Full size Ford custom A/C project

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Fairlane 500
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Full size Ford custom A/C project

Post by Fairlane 500 »

Hello. I can't remember if this is the same forum I was on or not. About seven years ago I decided I wanted AC on my Fiat 124 Spider. Seems at the time someone in Texas was making kits for about $1500 but I thought I could make one for a fraction of the cost. I didn't keep a tally but think I came out around $600.

Here are some photos of my build:

http://s222.photobucket.com/user/turbof ... t=6&page=1

These parts came from everywhere. I remember the most expensive part was the compressor. I had to go with a shorter Sanden compressor (can't remember the model number) rather than the standard 508 unit (which I already had two of) in order to clear the turbocharger. For some reason this compressor was actually more expensive than a 508. I have no idea why.

The evaporator unit says it's rated at 15000 BTUs. Since it was made in China, I kind of wonder if they are overstating it's capacity. The system works well on R134a and blows 45F air out the vents when it's in the 90s. Which is comparable to my 2003 Subaru on recirc mode. But I have seen other factory systems that blow colder air.

The main problem is the car is a convertible and it poorly insulated (yet the heater works great) so I have to run the AC on full blast. I took some of that bubble insulation and covered it with black fabric and glued it to the underside of the vinyl top. Before, I aimed a heat pen at the inside of the top one day and it was 140F! The cover that goes around the gear shifter get's hot enough to fry an egg on so I put some of that stuff around the gear shifter as well.

And there is not a driver's side outlet vent so the air has to just basically recirculate within the cabin. OH and whoever it sitting in the passenger seat freezes.

But I can ride around in shorts and a tee shirt in 90 degree weather and not break a sweat. I stay comfortable but if the car was better insulated, the system would do better.

The largest condenser I could fit was a 12X20.

I made one mistake. The fitting at the bottom of the condenser goes to the compressor and the fitting coming off the top goes to the dryer/receiver instead of the other way around like it should be. I did not catch this mistake when I was planning this project out until it was too late. However the system seems to work just fine. I pulled a vacuum on the system for about 30 minutes then put a full can of 134a and oil in it to start with and monitored the temperature then slowly added some more until the temperature stopped cooling at 45F. I asked an AC tech about this and this is what he suggested since I had no idea what the capacity was.

So I'm wanting to put an air conditioning system on my 68 Ford Fairlane. My previous project has left me with some questions.

When it comes to AC systems, bigger is better. I have more room to work with on the Ford but I'm faced with the same issue I have with my Fiat. The evaporator unit.

I have a unit that was installed on Fords back in the 1960s (not sure if it's any good) but it won't fit due to the space between the driveshaft tunnel and dashboard. I'm limited to about 5.5".

Looks like this system:

Image

BTW, I'm assuming this was some sort of dealer add-on system you could have installed through the dealership. Did this things cool all that well to begin with?

I found a system which says produces 22,000 BTUs. I decided to make a mock-up out of cardboard based on the measuremens just to see how it would look.
Evaporater unit.jpg
Evaporater unit.jpg (54.56 KiB) Viewed 5317 times
It looks like it would "fit" but not fit well. Especially for whoever is riding in the passenger side.

I can't seem to find any systems that are less than 13" deep. The one above measures about 11.5" deep and in protrudes from the dash about 3" more than I'd like for it to.

Two more ideas.

Remove the stock heater box and go with a heat and cool system and run duct-work to vents. A little bit more work involved but there is room behind the dashboard for ducting.

Second idea. If I recall the air conditioning/heater on my 1996 Ford Explorer was mounted in the engine compartment on the passenger side and channeled air through the firewall through ducts. I could use one of these. I think it would fit.

Then again, I could go with one of these smaller 15,000 BTU units and mount in the center of the dash. Once again it's 14" deep so it's going to stick out past the dashboard more like the mock-up I made:

Image

Although the Fairlane is not a convertible and is somewhat better insulated than my Fiat, I'm concerned trying to cool the interior of a car this size with a 15K BTU system is just not going to cool very well.

I do have an aftermarket evaporator unit I pulled from a Fiat Spider a friend was parting out. I'm pretty sure it would definitely fit under the dash but I think it's even smaller. Like perhaps 7000 BTUs.

Although the car is in good condition to be a 50 years old, it is not a show car. It's a driver. I don't want something that looks stupid but don't care if it doesn't look period correct. As long as it looks like it fits.

Every now and then factory A/C systems for the 68/69 pop up on Ebay and of course they go for big bucks which I am not going to spend.

One last idea. I've made allot of custom parts of fiberglass. I could use a donor system and construct my own slim line box out of fiberglass to conform to the underside of the dash. Mount the evaporator horizontally. Allot of priming and sanding (time) would be required to make it look nice.

Anybody got any ideas on this one?
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bohica2xo
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Re: Full size Ford custom A/C project

Post by bohica2xo »

Well, before we get in to the Fairlane...

Your Fiat A/C has a glaring problem that is costing you a lot of cooling. You need to correct the backwards condenser. Parallel flow condensers have a "Top" which needs to be up and the liquid needs to be collected at the bottom of the unit to be fed to the expansion device.

Those condensers are multiple paths with multiple passes. The number of paths decreases with each pass. The top will have perhaps 10 tubes in parallel on the first pass from one side to the other. the next pass will have 8. The pass after that maybe 5. As the gas condenses the number of tubes decreases. The last pas has the fewest tubes, and they should be liquid.


Now for the Fairlane. I actually owned a '67 Fairlane. Nice car, with lots of interior volume.


Depending on your climate the old "Knee Knocker" under dash aftermarket evaporator may be all you need. Because the evaporator is always recirculating cabin air they can cool quite well. There are plenty of versions of this type of evaporator assembly, still in production. The site sponsor has this offering that covers the tunnel hump issue quite nicely:


http://www.ackits.com/10070-evaporator- ... evaporator



The upside is you get to keep the great OEM Heater & Defroster, as well as doing a lot less under dash work. The downside is no fresh air intake for the evaporator - but old fords leak "fresh air" everywhere anyway.


Yes, Ford liked to hang half the HVAC hardware in the engine bay back then, so did GM. Many modern cars have a module behind the dash with both heater core & evaporator installed. There is a current thread here where someone has installed the package from a Crown Vic behind the dash of a '67 Catalina. But that is a lot more work to get fully functional defrosters, vents etc.


If I had my Fairlane back I would hang a slimline aftermarket under dash unit in a heartbeat. Then I would put the biggest parallel flow condenser I could in it & enjoy my car.

Which engine is in your Fairlane?
ice-n-tropics
Posts: 157
Joined: Sat Apr 23, 2016 3:40 pm

Re: Full size Ford custom A/C project

Post by ice-n-tropics »

Probably disappointing to use a 5.5 " high evaporator hung over the hump. I installed a Mark IV slim line under dash evap similar to the one shown on this web site in my 65 Ford convertible and drove all over USA with great cooling. By utilizing the passenger foot real estate and recirculation air only, A/C is optimized if a giant condenser is used.
Recommend a Sanden SD7H15 (154.9 cc) compressor instead of SD508 (138 cc).
Ditto analysis on rerouting Fiat compressor into top of condenser.
Heck with this 100 F Texas heat, I'm off to 2 weeks in Estas and Dillon.
hotrodac
Fairlane 500
Posts: 4
Joined: Sun Jun 24, 2018 5:15 pm

Re: Full size Ford custom A/C project

Post by Fairlane 500 »

Not trying to undercut the company that sponsors this forum but I think I found a system that will fit my Fairlane. I asked for some extra measurements on the left side and the seller provided them for me:

https://www.ebay.com/itm/Vintage-Air-Sl ... 2?var=null

I think I'll still have to remove the factory heater box because the unit will stick out about 1 or 2 inches past the dashboard. And the factory unit would probably block AC and heater hose inlets anyway. He says it has floor vents for the heating system. It's got two snouts coming off the back for the defroster vents but I was wanting to use one for a remote vent over next to the driver's side door.
Fairlane 500
Posts: 4
Joined: Sun Jun 24, 2018 5:15 pm

Re: Full size Ford custom A/C project

Post by Fairlane 500 »

>>>>Your Fiat A/C has a glaring problem that is costing you a lot of cooling. You need to correct the backwards condenser. Parallel flow condensers have a "Top" which needs to be up and the liquid needs to be collected at the bottom of the unit to be fed to the expansion device. Those condensers are multiple paths with multiple passes. The number of paths decreases with each pass. The top will have perhaps 10 tubes in parallel on the first pass from one side to the other. the next pass will have 8. The pass after that maybe 5. As the gas condenses the number of tubes decreases. The last pas has the fewest tubes, and they should be liquid. >>>>>

I'm really surprised the system actually works. It does blow 45F air so I figured it was working to it's full potential. Like I said the evaporator unit is supposedly rated at 15K BTUs but figured that was over stated. There could be something wrong with my 2003 Subaru which also blows 45F air on recirc mode and 55F air on fresh air mode that same day I took those measurements.

But you are correct. After all was said and done, I thought there would be mostly gas at the top and liquid at the bottom.

>>>Now for the Fairlane. I actually owned a '67 Fairlane. Nice car, with lots of interior volume. Depending on your climate the old "Knee Knocker" under dash aftermarket evaporator may be all you need. Because the evaporator is always recirculating cabin air they can cool quite well. There are plenty of versions of this type of evaporator assembly, still in production. The site sponsor has this offering that covers the tunnel hump issue quite nicely:

http://www.ackits.com/10070-evaporator- ... evaporator


The upside is you get to keep the great OEM Heater & Defroster, as well as doing a lot less under dash work. The downside is no fresh air intake for the evaporator - but old fords leak "fresh air" everywhere anyway.>>>>>

That one is still going to stick out about 2 or 3" past the dash. Does it have any vent ports to run remote vents over to the driver's side? That's one problem with the unit I installed on my Fiat. All the cold air hits anybody whoever is sitting in the passenger seat. But I will consider it before choosing a system.


>>>Yes, Ford liked to hang half the HVAC hardware in the engine bay back then, so did GM. Many modern cars have a module behind the dash with both heater core & evaporator installed. There is a current thread here where someone has installed the package from a Crown Vic behind the dash of a '67 Catalina. But that is a lot more work to get fully functional defrosters, vents etc. If I had my Fairlane back I would hang a slimline aftermarket under dash unit in a heartbeat. Then I would put the biggest parallel flow condenser I could in it & enjoy my car.

Which engine is in your Fairlane?>>>


Standard 302 / 8.5:1 C/R.

I kid this guy I work with who has a 68 Chevelle that mine will run on E10 87 octane unleaded and not knock or hesitate going up hills or under full throttle! I've ran 93 in it and it doesn't run any different.

He says he has to mix racing fuel and non ethanol gas in his Chevelle, otherwise it knocks and doesn't run very well!

As far as driving the compressor, instead of risking sheering off one of the three bolts holding the crankshaft pulley to the end of the crank, I don't see why I couldn't install a dual groove water pump pulley and drive the compressor off one of the waterpump grooves.

On another turbo project, I used a split crankshaft pulley to drive the waterpump and the waterpump drives the alternator.

I could use one of these kits and space the bracket out away from the block using longer bolts and flat washers to align the pullies if necessary:

https://www.ebay.com/itm/Ford-Small-Blo ... 3?var=null

It uses a rod with two heim joints to set the belt tension instead of a tensioner pulley.

I'm looking through this forums sponsor's list of parts but not turning up anything as far as a Ford 302 small block compressor kit. As of yet.

I'd rather not buy a "kit" because I have allot of left over parts from my previous build.

BTW, I actually have a factory (or dealer installed) system for a 63 Fairlane I snagged from a junkyard. The evaporator unit won't fit but I might be able to use some of the other bits and pieces. I believe the original compressor was made by York so I would have to do something to make my Sanden 508 compressor fit it.

I don't plan on using it or the receiver/dryer.

Any chance I could use the condenser providing it has no leaks in it? Newer condensers are probably more efficient anyway,
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