wwest

I was puzzled about your post as at first I was thinking air cooled Porsche and how in hell the inside of one of those could accumulate so much moisture within the cabin overnight.

Then I noticed that you're driving a 996....

Your A/C itsself is causing the high humidity within the cabin each morning...!!

Stop using the A/C and the problem will go away.

"Yesterday", when you shut down the car for the day the A/C evaporator was thoroughtly clogged, saturated with moisture, due to the day's operation, even on a relatively low humidity day. Most modern day A/C evaporators will have as much as 10,000 square inches of evaporator vane surface area "squeezed" into as small of a space behind the dash as can be allocated.

Think SPONGE.

Once the evaporator is no longer being cooled that condensate will begin to evaporate into the CLOSED passenger cabin.

You can combat this problem, mostly, by lowering the windows 2 or 3 inches overnight.

Or retrofit the car using an EED from airsept.com

But you 996 also has what can be a fairly serious design flaw in the climate control.

During the summer months once the climate control has cooled the cabin to with a few degrees of you setpoint some of the CHILLED airflow will be routed out of the windshield defrost/defog/demist ductwork. within an hour or so this can so thoroughly CHILL the windshield that on a relative humid day condensation will begin to form on the OUTSIDE of the windshield.

No biggy, right, just turn on the wipers....

But not if it's early evening, nearly dark, you've just driven through a rainstorm in AL in July and the windshield then fogs over so quickly you don't realize soon enough why your forward vision is/has declined so rapidly.

I have developed the practice of selecting and then deselecting the windshield air outlet flow path anytime I start the car and I have the A/C compressor clutch enabled.

dbryant61

KC911,

I have already removed my AC and heater fan and ducting, and I am re-installing heat with -74 heat exchangers. Do you know what parts I need on the topside to complete the heat?

Thanks

KC911

Don, I'm afraid I don't as my solution is unique to the '84-89 Carreras and utilizes an OEM 930 left side hot air duct and some OEM hose. I use the stock engine tin and connect to the hot air tube (unique to Carreras) sticking up next to the distributor as is depicted in the pic. That tube then diverts heat to both heat exchangers below. There are lots of threads over on Pelican with various options for particular years so you may find you answer in a search or just ask over there. I'm sure you're not the first on a '74. BTW, my heat works great, but I rarely sit at stoplights, etc. where the low engine rpms might not provide enough flow for some folks. Good luck!

Keith
'88 CE coupe

dbryant61

Thanks Keith. One of many "next project"s.

TT Oversteer

Keith, where did you source the 930 air duct sheet metal? New or used and what did it cost you? Was it a direct bolt-on or did you have to modify the fan shroud? Looks like a nice mod. My blower is not hooked up anyhow..........

sig_a

How does AC removal devalue a 1987 Carrera when the 21 year old system doesn't perform well enough to cool the car? One either repeatedly spends 100's to 1000's of dollars repairing and maintaining an obsolete R12 system, or updates to a newer R134a system. From a performance and cost standpoint, taking it completely out is a net plus. Even when new, the AC system was mediocre.

Todsimpson

Well, I wouldn't buy an '87 without AC, and I think many other buyers would want the original equipment in place, despite marginal performance.

911Dave

I generally agree, which is one reason I'm going to reinstall my A/C with some upgrades.

911Dave

I've spoken to several who bought these '80s cars new, and they all said the A/C worked great. I know its commonly accepted that they were always marginal, but I don't believe that's true. Very few (or none) of the people who frequent these boards ever drove an 80's Porsche when new.

If all the components, including hoses, are in good working order, it doesn't costs hundreds or thousands to maintain it. The only cost would be the annual recharge.

However, if it's a choice between a car with A/C removed and a car with non-functioning A/C in place, I don't think there would be much difference. In either case, it will cost a great deal of money and/or effort to end up with an adequate system in the car.

KC911

I purchased mine new from Pelican several years ago and like all 930 OEM parts, it wasn't cheap (around $175 as I recall). No mods to the fan shroud, but I did have to tweak the air duct a bit to get it to fit to my satisfaction and I did fill several holes with JB Weld (sanded down) and had it powdercoated while I was doing the fan & housing and some other stuff, so my "appearance" was not without effort (I don't want to mislead folks). To address some of the other points brought up, my '88 was a garage queen with less than 50K miles on her when I purchased, and the a/c actually worked quite well initially. I only used it a couple times my first two summers (I'm just not an a/c person) and it had virtually discharged itself by the time I removed it. Resale was absolutely not a concern for me (I've done a BUNCH of tasteful mods (mostly performance) to my car because she's MINE and just because I could. I'm sure some folks would pass on a non-a/c car, but I guarantee that if I put mine on the market, folks would be lining up and chomping at the bit...but that ain't gonna happen . These cars aren't special or exotic, do with 'em what you want is my attitude so long as it's "tasteful"...

Keith
'88 CE coupe

wwest

Provided you have a 911 has the extra condensor under the front nose, AND the blower to force airflow over that condensor is FULLY functional, (fuse not blown, no bird/squirrel/dirt dubber nests) the A/C operation will be satisfactory.

Otherwise I'm sure there is enough room under the engine lid mounted condensor to install two or three 12 volt "boxer" type computer fans that run any time the compressor clutch is engaged.

KC911

IMPORTANT (please read)!!! Although I have removed my front condensor & fan, Porsche did not add a 7.5 amp fuse for the front blower until '88. The earlier Carreras did NOT have a fuse, and the front blowers seazing up has caused many 911s to catch fire. If you have an '84-87 Carrera PLEASE add a fuse for the front blower to protect your baby. Lots of threads over on Pelican and it's an "easy" safety precaution upgrade. Hope this helps...

Keith
'88 CE coupe