I've got an '83 triple black SC with no working A/C. It can get hotter than two cats humping in a wool sock driving it around in the summer. System hasn't been converted to 134. Has the original York compressor. It is totally empty of refrigerant right now. Switch needs to be replaced. It seems the 134 conversion is a complete waste of time and money, so I've been contemplating one of the aftermarket options (including the new parallel flow condensers in the other thread).

Talked to a local shop to get some ideas. They recommended the RetroAir system. Said they just did a complete system for another customer with an '85 and parts and labor came out close to $4k. As Shaggy would say... "Zoiks!"

I'm still trying to figure out exactly what would be required.

The RetroAir system includes:

- Evaporator
- Condensor (multi-flow)
- Drier with hi/lo switch
- New center dash vents
- Barrier hose

Then I'd have to add new compressor. Blower upgrade is another extra. All that is $1800 in parts alone. That's a lot of coin. Might just have to continue living with my 2/80 A/C system.

IMMHO there is really only one design problem with the factory A/C, not enough heat exchanger capability. But we do need to address the issue of the need to annually top off the refrigerant level.

So I would start out converting to R134, but include a new dryer/rcvr, a hi/lo pressure switch, and 2 12 volt 2" thick 9" fans mounted inside the engine compartment to pull airlow down through the condensor even with the engine idling.

Assuming, as you say, you'd be starting out with an EMPTY system, all the above work could be DIY...<$300 even including the A/C specialist time for pump down and R134 installation.

I'd even bet that with the above modifications the front condensor blower could be tossed, and maybe also the condensor itself.

See:

http://forums.pelicanparts.com/porsche-911-technical-forum/622453-loss-refrigerant-theory.html

sometimes you need to think outside the box
 

welll I would not say "ALL AFTERMARKET STUFF IS NOT MUCH BETTER" he he he

sometimes you need to think outside the box

open your minds read and learn about something NEW designed for Porsche aftermarket

I make "PATENT PENDING" Parallel Flow Micro-Channel Condensers http://forums.pelicanparts.com/porsche-911-technical-forum/617196-i-make-parallel-flow-micro-channel-condensers-911s-front-rear.html

"..sometimes you need to think outside box..."

IMMHO you have needlessly designed and build "better" condensors when the OEM ones are more than adequate when considered one against one, yours against "theirs".

Obviously you are aware that the primary shortcoming is in the lack of the ability to convert ENOUGH HIGH pressure refrigerant GAS into a liquid state.

So, is the OEM condensor at fault...?

No.

The inability to more enough airflow over the condensor vanes is the problem, not the condensor itself in any way.

But, hey, using your "specialty" condensor in the rear deck lid position, do you NOT recommend adding blowers/fans along with...?

If not, that makes you the "goat" of the day (decade??), even Porsche knew that forcing more airflow over the condensor would improve system efficiency.

So why not try the blower/fans first and if that doesn't result in adequate cooling, rapid cabin cooldown rate, then start throwing money into the winds.

I recently read somewhere that in later air-cooled engine models Porsche used a technique to help cool the engine, engine compartment, once the ignition was off and/if the compartment temperature rose to too high a level.

Turned on the cabin heater blower.

True..?

Was this to protect the engine or was it to prevent the A/C from over-pressuring the o-rings, etc,....??

...
 

if i see another post for these parallel universe contoured condensors...i might have to buy one.
now---what else ?
electric fans attached to said condensors
who's blower
who's evaporators
who's condensor

again...the Ultimate System !

This is an interesting unit for DIY electric cars. At 500W through an inverter it might work. The price is nice too.

Electric Vehicle Airconditioner

Except that you'll need ~40 amps at 12 volts.

I have a hairbrained idea for heat/cold in my 914. An electric compressor with the condensor and evaporator both in the rear trunk and the air flow in a hose that runs through the engine bay and firewall - and switch that hose between the evap. and cond. as the seasons change. A 2nd hose to exhaust the other air through the floor of the trunk.

With a 2nd battery up front that would require plugin charge overnight, it could power it for at least an hour or two.

Just an idea for now.

Yes, the zero after the 12 is rather important. My engineering professors would be disappointed in me!

hair brained idea #x
small flap set around the rear condenser with actuator(s), when AC set to max. flaps better seal the condenser against the deck lid, when not set to max. engine gets cooler air and makes the front condenser take up the slack, this could be made light weight I'll bet