Electric A/C (Not Classic Retrofit) options

[jonesb930]

So a video popped up in my YouTube feed of a very inexpensive electric A/C option for classic cars (it even includes heat!). The entire under dash system was under $600. This did not include an alternator (that was needed) but basically everything else. The same company offers a similar system with an air box with 4 ports to use behind the dash. The main issue I see is the size of the condenser (14" X 18"). As I was interested in a behind the fender mount, this may be restrictive. The more I investigated though, I found a 12V compressor for $400. The question is, what would it take to adapt some of this stuff. The kit would be simple if you could find a place for the condenser I suppose and then connect up the ducts.

Here is a link to the kit: Amazon AC Kit

What are our options for Alternators to run these besides Classic Retrofits?

[mepstein]

Condensers are cheap. So are the electric fans that fit on them.

[SpyderMike]

Here is a write up on my hybrid AC system:

https://forums.pelicanparts.com/porsche-911-technical-forum/1144750-1985-ac-project.html

In it I have a cost roll up sheet. You will see that I used some of the CR components and some of the Griffiths. You could see the value of substituting some of those parts.

I went with a fender condenser and an under the chin condenser. It works great in Southern California...not sure how it would do in higher humidity locations.

One of the main benefits to the CR system, in my opinion, is the ECU controlling it and managing/protecting it and the car's electrical system. Without it, you have to manage it.

All that being said, give it a go! It could be a fun project.

[Jonny H]

Originally Posted by jonesb930

So a video popped up in my YouTube feed of a very inexpensive electric A/C option for classic cars (it even includes heat!). The entire under dash system was under $600. This did not include an alternator (that was needed) but basically everything else. The same company offers a similar system with an air box with 4 ports to use behind the dash. The main issue I see is the size of the condenser (14" X 18"). As I was interested in a behind the fender mount, this may be restrictive. The more I investigated though, I found a 12V compressor for $400. The question is, what would it take to adapt some of this stuff. The kit would be simple if you could find a place for the condenser I suppose and then connect up the ducts.

Here is a link to the kit: Amazon AC Kit

What are our options for Alternators to run these besides Classic Retrofits?

I think the link is misleading regarding the heat, there are not enough components for the system shown to be a heat pump, so ff it does have heat, it will be from a PTC but the heat output is not stated. The 2000W rated capacity for A/C will struggle with Florida temps. Our system is double that output.

Our system works because of the power management software in the ECU. Without this, when the engine idles, the battery voltage sags and the compressor goes into a fault mode.

There is no way you will fit any off the shelf evaporator/blower 'behind the dash' - unless you don't mind it invading the luggage bay and looking like a dog's breakfast.

Regarding the alternator, I will save you the bother of all the 'just rewind the stator' answers. Our journey started with that approach almost ten years ago. We tried 'rewinds' of the Carrera 3.2 unit for 110A and 130A.

Although they all produced the required power, the triumph was short lived. In every case, the insulation overheated, causing the windings to short out. I set fire to 3 alternators and almost torched my car in the process! It is no fun trying to remove a smoldering alternator from a 911 in a hurry.

The issue is that the standard alternator does not have an internal fan so it cannot dissipate the heat from the extra windings. And no, the engine fan on a 911 does not cool the alternator, in fact it is a hinderance as the alternator is trapped inside it.

Good luck!

[rdimarco]

Bill,
FWIW I run a single 12 x12 generic condenser in the LF fender. With good air flow, it's enough for plenty of cold air. I have it ducted from the brake duct in the spoiler with a 12" puller fan behind it. I'm still running an engine driven compressor. I have cold AC, but it would be nice to get some weight off the rear.
I have the CR alternator, puts out good clean voltage at idle.

[jonesb930]

Originally Posted by rdimarco

Bill,
FWIW I run a single 12 x12 generic condenser in the LF fender. With good air flow, it's enough for plenty of cold air. I have it ducted from the brake duct in the spoiler with a 12" puller fan behind it. I'm still running an engine driven compressor. I have cold AC, but it would be nice to get some weight off the rear.
I have the CR alternator, puts out good clean voltage at idle.

What from spoiler are you running on your car? Can you post a pic?

[jonesb930]

Originally Posted by Jonny H

I think the link is misleading regarding the heat, there are not enough components for the system shown to be a heat pump, so ff it does have heat, it will be from a PTC but the heat output is not stated. The 2000W rated capacity for A/C will struggle with Florida temps. Our system is double that output.

Our system works because of the power management software in the ECU. Without this, when the engine idles, the battery voltage sags and the compressor goes into a fault mode.

There is no way you will fit any off the shelf evaporator/blower 'behind the dash' - unless you don't mind it invading the luggage bay and looking like a dog's breakfast.

Regarding the alternator, I will save you the bother of all the 'just rewind the stator' answers. Our journey started with that approach almost ten years ago. We tried 'rewinds' of the Carrera 3.2 unit for 110A and 130A.

Although they all produced the required power, the triumph was short lived. In every case, the insulation overheated, causing the windings to short out. I set fire to 3 alternators and almost torched my car in the process! It is no fun trying to remove a smoldering alternator from a 911 in a hurry.

The issue is that the standard alternator does not have an internal fan so it cannot dissipate the heat from the extra windings. And no, the engine fan on a 911 does not cool the alternator, in fact it is a hinderance as the alternator is trapped inside it.

Good luck!

Thank you for chiming in. Believe me, I like your system. With my build having a front mount electric compressor is really my only option due to the charge piping I am planning for the twin turbos. I may have to piece my system together over time to spread out the cost. It looks like starting with the alternator and wiring would be good plan since it's apart and I will be rewiring most of the rear of the car.

If I took this approach, what components could be installed and used along the way other than the alternator? Any improvements you recommend while it's all apart?
Bill

[pmax]

Originally Posted by jonesb930

...
What are our options for Alternators to run these besides Classic Retrofits?

Given this sounds like a ground up install ... why not an external alternator mounted where the stock AC compressor is ?

Not sure how long that would last given the rpms but hey, it's a project.

[rdimarco]

Originally Posted by jonesb930

What from spoiler are you running on your car? Can you post a pic?

RSR bumper with a splitter. The splitter helps force more air through the condenser.

[Duc Hunter]

My bumper solution is a modified 934 bumper. After running this system behind a IROC bumper with the coolers in the fenders, and no airflow from vents (system worked fine in Florida) I went to this look. I don't think the system will cool better because of the airflow over the condensers when the car is moving (like on the freeway) because the fans do a pretty good job. Before the systems was great. I wont know for sure for a few more weeks, when I finally get her back on the road.