savage944

I was wondering in the course of thinking about mild upgrades... instead of deleting the AC setup for to save weight. Why can't we just upgrade to a better compressor that is lighter, smaller and doesn't rob as much power from the engine.

Anyone ever consider this. I mean in essence you just match the Compressor output to whats required for the car, find one that is sufficient with a pulley that is smaller. I mean come on, some 4cyl engines have some very small highly efficient compressors, and well, the units in are cars are 20 years old. I don't mean upgrade to a new compressor from porsche, unless it does what I want.

I mean bastardize something, also convert to 134 at the same time. Saves some weight, not a lot, but some and would decrease the amount of HP lost from spinning that big compressor.... its just a thought.

Can anyone comment on this, suggestions, thoughts.... etc.

I want to keep AC in the car, but no reason why I can't improve on it.

Perry 951

Do a search for a Sanden or Kuhl compressor.

Graufuchs

My AC never worked, becuase of leak in the system, no reason to hual an xtra 50 pounds around...and awaste a few horses too..-chris

savage944

Perry thanks.

fty, you make a good point, but I want AC, and to save weight and reduce the draw on the crank, blah, blah... I hope I find something good on the Sanden or Kuhl compressor.

Hemm add the weight reduction up with a lighter alternator....

Perry 951

We swapped out the OEM compressor with a Sanden unit on my fathers Supercharged 911 SC. We did a dirty conversion from R-12 to R-134a and it worked perfect. (Until we removed the exchanger in favor of an intercooler)
I think Performance Products may have a 944 kit you can check out. At least you can get an idea of what you need.

While we're at it.. here's a quick step by step for a conversion from R-12 to R-134a:
1. Order supplies. (For the 944)
- O Ring Kit From Paragon
- Drier
- Large Syringe (Medical Supply Store)
- 12oz Ethyl alcohol, or a bottle of flush from your local parts store.
- 12 oz R-134a with dye charge
- 18 oz R-134a
- 3oz R134a compressor oil
- R12- R134a adapters
- R134a Charge Manifold
- Vac Pump (ask around here if you don't have one, or see a shop after you convert)


1. Evacuate system. If it is currently charged, please have a shop drain it. They'll most likely do it for free since they can get $$ for recycling.
2. Replace all O Rings (the ones on the firewall are fun!!) and attach adapters to lines.
3. With the drier out of the car and the lines disconnected to the compressor, fill the system with 6 oz of Ethyl Alcohol.
4. Blow out in short spurts with compressed air. Continue blowing air until no liquid comes out . Repeat again with the remaining 6oz of Alcohol.
5. Inject 3oz of oil into one of the lines.
6. Attach lines, drier, and manifolds.
7. Pull 30hg of vacuum from the low side for 1 hour. Remove hours.
8. Remove pump from system and make sure vac stays steady after 1 hour.
9. Insert 12 oz Dye charge.
10. Start car and turn AC on high. Add remaining 18oz of R-134a. (a digital scale helps a ton to get an accurate amount of charge in the system)
11. Check for leaks and be cool.

Ideally, you'll want about 210-230psi on the 944's high side, about 15-40psi on the low side.

Danno

You have to get away from evaluatating things based upon black & white, all-or-nothing, yes/no criterias. Comes down to bang-for-the-buck values, or in this case, pounds-saved-per-dollar spent. Using that criteria, the best weight-savings values are in things that you spend zero dollars for. Stripping out the interior, spare tire, insulation, sound-proofing, etc. saved me about 253-lbs. The entire weight of the air-conditioning system, the compressor (12-lbs dry), condenser (9-lbs), hoses (5-lbs), etc. all combined to be 45-lbs. That includes the heat-exchanger and heater-core. So the absolute most you can reduce in weight on the air-con. system is 45-lbs and that means you lose the heater as well. That's about the same weight as the spare tire. I'm not sure how much an air-con. compressor costs, but if you actually found one that weighed 1/2 of the original, you would have saved yourself 6-lbs. That's 1 gallon of gasoline. Just drive around with less than half a full-tank all the time and you will have multiplied your performance increases by a factor of 9x.

BTW - the compressor has a clutch on it and will only put drag on the crank when your AC is on. Also when you floor the car, the compressor is disengaged automatically.

Race seats make a good upgrade. Motorized Porsche seats weigh about 45-50lbs each. Two race-seats @ 12-lbs/ea will save you 86-lbs, or about double the weight savings of ripping out your entire AC/heater system. Also the rear glass weighs about 80-lbs. Getting a plexiglass/Lexan piece will save another 40-60lbs depending upon whether you keep that solid rubber wing or not. Another 100lbs can be had with carbon-fibre hood, fenders, doors.

savage944

Danno, more good points!!

I am going with a lot fiberglass parts, in fact, if you have seen some of my other posts, I am working with someone to develop some parts. I am getting race seats etc... but everything in the car is a compromise of some kind.

I want to keep the insulation and the AC, I also want to improve on its performance and thought maybe I could save a little on the weight.

I am well aware of the clutch setup, so yea only and issue with it on and not accelerating.

My car is intended as a Daily driver, but like just about everyone else I want performance to.

I can see upgrading the AC will be something I will do just to increase its performance. I conceed that their isn't much to be gained other than that in the upgrade, only in deleting the AC. The AC upgrades are about the same in weight, so not much difference other than a gain in AC performance.

Peckster

It's got to drop the resale value way down not having AC.

turbo944

There are better places than Performance Products to buy the A/C kits. 944online.com has one for $499 and Griffiths has a kit with the Kuehl for $599 (last time I talked to them about a year ago) for the kits to upgrade the compressor and convert to R134a. Performance Products didn't list a kit for the 86 944 Turbo at all...just a "rebuilt" Denso compressor for $7xx!!!! Yikes! They had some other rebuilt compressor for a bit less, but these kits are new compressors and new driers and kits. Maybe I didn't see the kit there at PP for some reason....think I'd go with one of the above anyway, personally.

Perry 951

Once upon a time they had one.

That was no endorsement for them by me anyway.... many of you know I'll never buy from them again, but I'll check out their nice catalogs.

Bryan

Cars with factory AC delete also have one less electric fan, a smaller fan shroud, and less wiring running around the car - and wiring is heavy. I have a carboard box with some old wiring harnesses wrapped up and stuffed in it, and it's a really heavy box.

So there's a little more - or less - to it that the 45 lbs. Not much more, but a little.

But the weight penalty for AC doesn't really seem that extreme. For me, living near Boston, there's maybe a week or two per year where you wish you had AC. The rest of the time you're just carrying it around. So you can easily live without it. Compared to the expense of maintaining the system, I'm better off with AC delete. In Miami, yeah. I'd keep it.

Bryan

iloveporsches

If you don't plan on selling, that really doesn't matter does it? Plus it's broke on my car, and I'd rather take it out and maybe fix it that way, instead of paying hundreds of dollars for it. I swear, 100 degrees + 99% humidity + black on black isn't that bad!

SamGrant951

Resale value? Whats that?

Silverbullet951

How much does the rear seat weigh?

tifosiman