[eyell]

I have a hole in my firewall that appears to be for AC. Were these holes there for all cars or only cars that came with AC?

[Ivy66GT]

There was almost always a dimple in the sheet metal to tell the assembly guy the correct location to punch holes for optional equipment. For the A/C there were two holes (3-4" apart) needed for the 2 hoses and there were dimples for them. The actual holes would only have been there if it were an A/C car.

[eyell]

I hate to disagree with you. However, in my limited research i have fount that there was an oval hole with a rubber gromett. I have seen the gromett at several parts places. What i was wondering was if there was a blank installed for future installation?

[Ivy66GT]

If you knew the answer beforehand then why did you ask the question? By doing that people will learn to not answer your future questions.

Below are the photographs of two original 1966 firewalls. I am only assuming you are talking about an early car, you didn't say. The first is a Dearborn A/C coupe. Those hoses have NEVER been out of that firewall since installed in March 1966. (The extra pair of blue and red connectors are for the C4 wiring. The wires are the lower left are non-factory cruise control wires.) The second, with dimpled sheet metal, is a non-A/C, 4-speed, San Jose Convertible (no C4 wires). There was a knockout formed in the metal but it was not knocked out unless you had A/C. Ford was not going to do extra work and add extra parts if you didn't buy A/C.

BTW, tell me how I was wrong other than the dimples are only 1 7/8" apart.

[rex1965]

My 65 fb which was never a AC car has a metal plate in the engine compartment covering the oblong hole with a bolt holding it, and it is sealed in the engine compartment. I can't tell if there are dimples as the sealer is about an 1/8 to 1/4 thick in this area. The year of the car may a difference as to what Ford did. My 2 cts.

[Nashville'65]

I did an after-market AC install on my '65 a couple of years ago...too hot in Nashville in the summer! Anyway, there was an existing hole already in the firewall covered with a small rectangle of sheet metal, which was spray-sealed from inside the engine compartment. This was not an AC car originally. I know the production line was far from "perfection" back then...the 65's sometimes have quirky differences. It's possible some cars were produced with no hole (only "dimples")...but when those firewalls were running low they might have grabbed the "AC car" firewalls on the line and closed the hole up with the sheet metal....to keep production rolling. Just a thought... Sorry I don't have any pictures...