Installing AC on a '69 911 w/o factory AC

[78-911SC]

Kuehl thanks for taking the time to add the pictures. Makes that part of the project look more attainable. Still in the body work phase. Is there anything I need to know or do to make the routing of the lines easier or maybe more hidden or neater? Dave I would say my DIY skills are a 7 out of 10 and I have a good friend that restores model A's and just finished a beautiful 28 Nash roadster. He makes up the rest of the 10 with equipment and knowledge. That being said I hope I can accomplish and fix any issues.

[matt930s]

I also have a 69 911 e that I plan on adding AC to in the future. I have a complete brand new after market AC system sitting on a shelf in the garage. Look forward to your progress.

MattR

[kuehl]

PJ,

In essence, the installation of AC in a pre 78 vehicle, that did not have AC, is a mirror of a typical SC or Carrera system, other than the vent system (early models did not have sufficient room in the dash for vents hence the knee pad vent systems): The variation or difference between your LH drive vs. RH models is only the location of the evaporator system and vents; I assume we are discussing LH models naturally but we also support RH models.

My preference for vents is the old 6 louver Behr panel, it has the best distribution, otherwise there is the old VPC 4 louver unit however the evaporator box and its installation is much different. Some 77 models, and 78 forward, all have vent distribution capabilities in the dash, and you would improve upon their side vents, via Kuehl Vents.

Using a Behr evap box allows more choices in evaporator designs, and naturally I am "biased" with the Kuehl evaporator because it can absorb more BTU's from the cockpit, and the pre 86 Behr evap box top allows you to use either the OE Bosch motor or the higher 30% more output Kuehl Hurricane evap motor: moving lots of air is critical in maintaining cockpit comfort in a 911/912/930.

If the engine has a single groove crank pulley you just need to locate a good used 2 groove unit; some pulley's have different markings; i.e. mechanical FI.

To install the compressor mounting brackets you will need, simply, to trim an inch or less strip off the rearward steel surround panel adjacent to the engine "console" (the steel weldment attached to the rear or pulley side of the engine).
I probably have a half a dozen pictures of the install I did in my 73T.
For the pump (compressor) our preference is the Kuehl 507 or a Sanden if you wish. The capacity is perfect for the size of the cockpit and its foot print in the engine bay leaves plenty of room to play in there.

Hose routing is typical of any SC/Carrera or early body with Behr factory air. Behr air has the drier in the LH front fender, whereas VPC systems located the drier in the RH front fender; we prefer typical LH locations. Hoses in the engine bay are very easy to route in and out; you do not need reduced barrier hose, just normal barrier hose diameters. The factory hose path back to front or front to back is under the tub, very simple and acceptable. Some have routed hoses through the rockers however we prefer not to touch their integrity, its all a personal choice naturally.

Condenser capacity is all relative to your climate, vehicle characteristics, and personal needs. For example, a vehicle in northern Oregon does not require what a vehicle in Texas or lower central Florida might need. A black vehicle is more difficult to chill vs. silver or white. One occupant vehicles require less than two occupants. A typical condenser layout for most moderate climates is: engine deck lid and 2 Kuehl units in the LH rear fender; everything simply bolts right in, very non-invasive. If you need more cooling then a front Kuehl unit.
There is another thread going on now discussing installation of 964/993 unit hacked into the LH front fender, if you are keeping the OEM fan/motor in the design you might be OK with just that, some replace the OEM fan/motor with a flat Spal but you will lose CFM's and performance. Again, condenser can be personal choice, however there is a minimum required to do the job.

Control wise; thermostat and fan speed switches in the existing Behr panel. I'd replace the old thermostat, and if you are intending on using the factory fan speed resistor pack I'd inspect the thermal contacts and install a new switch, or you could step up to Kuehl Variable Speed unit. Some have mounted controls in the dash or simple bracket under the dash.

The circuit to power it all is shown here: AC Circuit
You could build your own harness but we usually incorporate a good used SC or Carrera harness; why re-invent the wheel. I'd plan on 45 amps overall, most stock alternators can easily keep up with it.

The discussion assumes common R134a which is available across the States; a handful of countries are attempting to phase it out however it will be here in the US well after you retire the vehicle.

In terms of technical support with Kuehl products purchased through Pelican, we included detailed instructions and you can always contact us directly. If you are considering entertaining a complete Kuehl system, or any Griffiths/Kuehl product PP has not yet added to their catalog, we can support you as well naturally. We have helped quite a few owners install complete systems over the years and I say most are satisfied. The project does take some time, maybe 35-40 hours of love, but if you plan it all out as you are now, its rather easy, fun and quite rewarding. Cost wise....personally I have no issues in investing in a nice vehicle I can drive year round, and in most cases, if you do the job right the investment is recoverable at time of resale; after all wouldn't you prefer to buy a car with a good system.

In terms of skill level to do the work, anyone with common tools, a place to work comfortably on the car, can do the work; if properly rebuilding a complete engine or tranny was a skill level 10, this project is a 5.
There are plenty of knowledgeable peer car owners, whom, "AC wise" have been there done that, here in the forum to support you. And, if you search all the AC threads in the 911 forum, and have a sense of humor when you come upon an "AC Thread", its all here for you.

[78-911SC]

Wow kuehl thanks so much for the info. A lot to digest. Just a update on my project it is a 70T in really nice condition that I'm trying to keep as close to original with a few exceptions. I want to make it with some conveniences such as the ac, suspension, and engine(3.2)/trans(915). The engine (3.2) already had the compressor on it and I have already fitted the engine/trans with compressor in the car and modified the electrical harness. Ran for a few weeks to eliminate some of the bugs and than stripped the entire car. At this point I'm doing the body work (stripping the paint and looking for rust). Will be keeping all the original parts so that if a future owner wants it all original the parts are there. The Behr unit I have is the 6 vent unit. The compressor is a Nippondenso 10P15C R12. Not sure if that info helps you or if the unit is sufficient for the task at hand or needs to be upgraded. I have a condenser that I believe came from a SC/ Carrera deck lid. I also have a factory fan speed resistor pack. Was going to run the barrier hoses through the rocker panels but I'm going to give that some more thought. Again thanks for your input it has given me a good roadmap.

[Jack Stands]

I seem to remember that the mid 70's cars used a compressor mount that attached with 6mm studs onto the chain case. Do the later style mounts work with the early style heat exchangers? I don't know how much clearance there is for the passenger side air duct hose with the later style AC bracket. Anyone have any pics to share?