1985 Mustang GT AC on a Non AC car?

[racerxmd]

Hello. I’m wanting to install a complete ac factory system on my non ac equipped GT. I started purchasing parts but concerned about the fire wall. Do both the non and ac equipped car Share the same Firewall! Just want to make sure one way or the other. Pics would really help out.

Thanks

[tbirdman]

http://vb.foureyedpride.com/showthre...ry-AC-question

[massacre]

I have a factory non AC car and the firewall is different from my buddy’s car that has AC. He has the holes for the AC components, mine does not.

[racerxmd]

So are the firewalls the same but just have different factory cut outs for ac equipped and non ac equipped? Can I just cut out large rectangular area that’s is recessed for the ac accumulator? Then hole saw new holes for heater core?

Thanks

[RED 78']

Yes, you need to cut out a hole in the large square area, holes for the heater core, a hole for the drain plug, and box mounting holes.
Here is what mine looked like when I removed the engine to upgrade the A/C to the newer version and to redo the engine compartment.

[wraithracing]

The Mustang and Capri both use the same firewall for the A/C and Non-A/C cars. My 79 Pace Car was a Non-A/C car and I cut out the firewall and install a 1985 A/C unit. The 79-81 models IIRC used a slightly different A/C setup than the 82-93 cars and the firewall didn't actually have the raised or embossed areas for the A/C openings. I used another Fox with factory A/C to make a template so I could cut out the areas needed. Worked perfectly and many people would not be able to tell that my car isn't a factory A/C 79 PC if I didn't tell them. Your 85 will have the raised or embossed area for the large evaporator core opening. I will warn you that the heater hoses do exit the firewall in a different location so you will have to decided what to do with the original heater hose holes once you have completed the conversion. Good Luck!

[gr79]

Could plug the unused heater holes with round rubber body plugs

[massacre]

The other difference I noticed between the AC and non AC cars, is the dash panel for AC cars has an extra cutout for that extra vent outlet.
My dash panel only has 2 vent outlets, 1 each at extreme left and extreme right of the dash. These are for the fresh air vents.
My dash does have an empty space in the middle for another vent outlet, but the dash panel does not have the opening so it is blocked off.
So you would need to add that extra vent outlet in the middle, and either cut the square hole or just get a dash panel from an AC car.

[at_the_junkyard]

FWIW its been a few years but I can confirm when I added AC to my non-AC 80 cobra the firewall is somewhat dimpled in the right places to cut if I remember correctly. The drain condensate drain tube off the bottom of the heater box into the engine bay also needs to be cut. It's all doable but takes some time and effort to get it all positioned and mounted correctly in the new holes etc. You want to make sure the heater box is high enough that the blower foam seals good to the passenger side air intake after it is installed.

Massacre is correct I also had to get different dash bezels on both sides as the ducting has two AC vents on each as opposed to one. These can be difficult to find sometimes as well but not impossible. I might even have some spares if your desperate.

GR79 is correct I think I actually used some rubber body plugs to patch up the old heater core holes a bit.

Another thing that is overlooked sometimes is the hole on the driver side cowl after the manual vent is removed. I believe I just trimmed down my old vent and fastened a block off plate with weatherstripping to seal up the hole.

Also don't forget the vacuum sphere that goes under the passenger fender well. Not 100% sure if its really needed but I think it provides a bit of vacuum capacity for the controls.

In the end I was pleased with how it all turned out. Nice to have that AC and with the factory correct parts !!

Cheers

[RED 78']

See post #6 on this thread. Most questions can be answered there.
http://vb.foureyedpride.com/showthre...ox-in-fairmont

[at_the_junkyard]

Here is another link for your info. JACook helped me a lot with the conversion back then. I was lucky to find an 83 donor car.

http://vb.foureyedpride.com/showthre...-to-1980-Cobra

[ponch85rs]

The wiring harness work alone is gonna be insane.

[KevinK]

There is not much to the ac wiring. Just 2 maybe 3 wires in the engine compartment (compressor and low pressure switch). The rest is between the controls and the box.

[jacksonliam341]

The Mustang and Capri both use the same firewall for the A/C and Non-A/C cars. My 79 Pace Car was a Non-A/C car and I cut out the firewall and install a 1985 A/C unit. The 79-81 models IIRC used a slightly different A/C setup than the 82-93 cars and the firewall didn't actually have the raised or embossed areas for the A/C openings.

I used another Fox with factory A/C to make a template so I could cut out the areas needed. Worked perfectly and many people would not be able to tell that my car isn't a factory A/C 79 PC if I didn't tell them.

Your 85 will have the raised or embossed area for the large evaporator core opening.I will warn you that the heater hoses do exit the firewall in a different location so you will have to decided what to do with the original heater hose holes once you have completed the conversion.

Gordon Bullard & Company