https://www.googleadservices.com/pagead/acl...ct=1&adurl=
Just add Under Dash Evaporator, Condenser and dryer!
Example install, but mine is a Benling
Click to view attachment

I just ordered the classic retrofit a/c kit. It’s for my ‘67 912 (with a 3.2) but I’m going to check the fit of the blower box against a 914.
Is your electric a/c working?

Not yet.. I still need another fitting and then charge it. I was just surprised to see a 12vdc compressor on Amazon.

Electric AC for autos is the future. No belt to suck HP even when not in use. Just need an alternator and wiring to supply the power. I believe most autos today have E-AC. Likewise the power steering is electric now again, no robbing HP if the assist is not needed.

I just clicked on your link and Amazon also suggested this unit at $335. Not sure if it is apples to apples comparison though.

https://www.amazon.com/AUTOMOTIVE-CONDITION...1_t1_B09TPF1Y46

Not planning on installing AC in my car, but with these becoming more accessible, I will keep it in mind...

I run an automotive AC specialist shop.
I deal with modern AC systems every day.
I have customers who have brought BRAND NEW vehicles to me that the AC doesn't work to their expectations to have a NEW vehicle fixed as the dealers cannot actually fix anything.

They just replace parts...

The only vehicles I've seen with electric compressors are a very few hybrids that have fully electric compressors. The common ones are the Toyota Prius and the Cadillac Escalade hybrids.

Both of these use a Mitsubishi compressor (the same basic beast) and are running 600 volts to the compressor.

Most other hybrids still use a standard compressor that is belt driven.

All ICE engines vehicles I've hit, even brand-new ones, use a standard compressor.
They are all variable displacement computer-controlled compressors, but they are NOT like a Mitsubishi electric.

A true electric compressor takes special care to repair as the oil HAS to be di-electric.
You put normal PAG in one of these and you kill the system INSTANTLY!

Toyota's suggestion for a poisoned electric system is to replace everything the refrigerate touches. ALL of it!
Dash out for evap, all lines, condenser, compressor, all switches, everything!
On a Pruis it touches 7K!
On an Escalade it's more...

I believe I could clean one of these out and re-use some of it, but it would still be massively expensive.


Each time you change power from one type (mechanical to electric and back) you will lose some efficacy.
If you could make a change at 100% you will end up being the richest person on the planet as this is the path to perpetual movement.

All modern ECUs reduce power loads (de-stroke and disco clutch on a compressor) above a specific RPM, throttle angle, and speed of throttle angle change.
So, when you hammer the throttle on your 2012 Chevy truck, it takes out both the compressor and the alternator instantly.
It will also take out the compressor with a serous engine problem. If the check engine light is flashing (bad!) your AC will not work...

The days of an AC system reducing power when power is demanded are long over. That stuff started happening in the late 80s and by 2000 power robbing was no-longer an issue.

I'd be DAMNED careful regarding the oil and system cleanliness when installing any fully electric compressor.
It would need to be "medically" clean IMO and I would make damn sure about any additional oil I added to the system.
I am especially leery of the claim on Amazon that "compressor is filled with oil and no extra is needed..."
How do they know how big your system is?

A modern Chevy truck needs less than 4 ounces total but a Tahoe needs 8.
Same compressor, same condenser, same puppy except one has an additional evaporator and 20 feet of lines and needs more than double the amount of oil...

I was forced to install 6 Chinese compressors last season as I could not get OEMs anywhere.
All 6 failed!
I know what I'm doing!
I lose 1 out of 200 OEMs...
So, a 100% failure rate versus a 0.5% failure rate.
You do the math!

When they failed, they came apart internally and trashed the systems.
So, it was not just replacing the compressor.
The repairs included finding an OEM compressor (or having the original re-built), replacing the condenser, desiccant package, expansion device, and a complete flushing of everything. Each failure would have been a 2k+ job by itself.

Chinese compressors have cost me over 12K!!!

I will no longer install Chinese compressors.

I might try an electric from a brand name company. These are Denso, Sanden, Calsonic, Harrison/Delphi, Panasonic, Diesel Kiki, Mitsubishi, and others.
Haven't seen electrics from any of those companies except Mitsubishi.


No-names get thrown in the trash...

I am looking into a retrofit using the Mits compressor from an Escalade for "pro-mod" street cars including the big assed battery. Have to figure out how to charge this battery via a house charger and I believe AC alone the battery would last 8-10 hours.
The Escalades take a long time to cool down but...
The Hybrids pump 35-degree air where the non-hybrids turn off the party at 45.
Mitsubishi beats Chevrolet (Denso) in this regard.

OK, who is going to be the guinea pig and buys one of these Chinese made "complete systems" for $885 and puts in into his 914 to become the coolest kid on the block?

Not true

EVs yes but they are using high voltage (300v or more) to the compressor. Conventional ICE - no.

Too much power draw on a 12v system.

Look at the spec’s on these 12v electric compressors - in the range of 75-100 amps.

Your average ICE powertrain is not equipped with an alternator large enough to handle that sort of load. Even on something like a F150 with a (huge) 200A alternator, the electrical system cannot support an incremental 100A draw for electric AC.

Might also want to look at the compressor displacement on these units - not very much displacement compared to normal automotive AC compressors.

Electric ACs work.

I know, as I have one in my 911.

Phil is correct about needing a lot of amps. I believe someone on here once had an alternator upgrade kit for around 175 amps??? A simple search would probably find it. Anyway, I might try it, if i still had a 914

Some trucks have DUAL 200-amp alternators!

It's a BITCH to figure out which alternator has gone bad, and many shops replace them together.

They are not inexpensive.

You could upgrade the 914s electrical system with the hotrod alternators found on this site.

http://www.914world.com/bbs2/index.php?showtopic=195244

Use two big assed 12V batteries. Diesel Truck SIZE.

This might work in warm environments where highs seldom exceed 95.

I think the alternator would have a shorter service life and you might have to go serpentine belt to provide the torque the alternator will require.
The alternator might require updates to its cooling system as well.

Lot of extra stuff and weight IMO.

When the Chinese compressors turn out to have 6-month service lives...
You might regret going this route.

Clay Perrine is going this route; he has his head on straight and his dad was involved in the engineering of automotive AC systems. He has a better chance of pulling this off than anyone I know, and I will be watching his progress closely when he walks this path. He's down here in North Texas as well so the test climate is appropriate.

I'm going old school "modern" and will be using a serpentine belt driven variable output compressor that is significantly over-sized for the 914 cabin.
I will be using multiple small condensers and try to use the original under dash unit as it is not a bad design IMO.
I may initially use a mechanical variable displacement compressor instead of a PMW controlled one. This compressor can be "tuned" usually and offers most of the benefits of a truly modern computer-controlled compressor without any wiring or computers at all.
VWs from 1995-2005 had a bunch of these.
Best version for me would be a mechanical variable scroll that doesn't care about direction of rotation.
The Delphi V5/V7s are this style; they are too big IMO and need to rotate clockwise.
Those square York compressors that the 914 originally used did not care about direction of rotation. One of a very few compressors that will live fine either direction.
All compressors except vane style will actually work (pump) either direction. They just won't live very long the wrong way...

One NICE thing about variable displacement compressors is that they always try to apply exactly the perfect amount of refrigerant to attain a specific pressure on the suction side. Once your car cools down the Variable will ALWAYS have the lowest power consumption and create the minimum amount of drag on the engine. These were engineered and installed with fuel economy as their focus. Properly configured these can create the very lowest system temperatures as well. Only downside is that they are more expensive, fragile, and fail sooner.

If it's a variable scroll you cannot tell it's on at all and you usually do not need to add throttle to maintain a steady idle.
It's "transparent"...

It is worthwhile to note that the Mitsubishi fully electric compressor is a variable output scroll. It's just driven by an electric motor.

Tangent:

Anyone ever documented the dealer installed systems? They were R-12 systems but could be used to infer sizing and efficiency of something more modern. I took a DPD system off my car and scrapped it and didn’t think to measure what it was assuming info was readily available but I haven’t run across it clearly documented.

Compressor: York - but wonder what the displacement was.

Evaporator size: ?

Condenser size:? I guess I could estimate based on the size of the hole cut into my frunk.
VPC manual specifies 19” x 13” cutout for condenser.

Oil capacity: 28 oz according to VPC manual

Refrigerant: 2 1/2 lbs according to DPD manual

Pulley ratio: ?

Keith @914Toy installed an electric compressor and I believe he has had excellent results. IIRC, it is Chinese and an eBay item.

My camper uses propane.... I wonder about an ammonia system?

I just bought the high capacity alternator from classic retrofit for my a/c install. It was $995. Stung a bit but it’s needed for the system to work correctly.

With the flat fan, I have to have a different alternator setup because it came with a 55 amp VW rabbit alternator. And that is way too small for the amount of amperage needed to run a 914 with aftermarket fuel injection, much less the AC compressor. And I have to mount it lower than the original 935 setup to clear the firewall.

So I am going to run a high output 300 amp GM hairpin alternator. That alternator is designed to be controlled by the ECU, and I will be using the MS3Pro ECU to control it's output. It is a serpentine belt design and can be mounted lower where the distributor used to go on the 964 engine, so it will clear the firewall, and it will use the serpentine belt setup I have from Clewett to spin it and the fan with the same belt.

The AC compressor is a scroll style compressor that, according to the documentation, only draws about 135 amps at max cooling. I will have it controlled by the ECU too, so the alternator can be told to increase it's output, and the engine idle speed will be increased to compensate for the compressor's load on the electrical system.

I am also going to run a parallel flow condenser with the biggest fan I can find to pull air over it. There will be a big flap to make a low pressure area behind the condenser.

All of this is an attempt to engineer a complete electric AC system, not just band aid an existing one. I am transferring the load of an engine mounted AC compressor to the electrical system. There will be losses in each transfer, from circular engine motion to Alternator, from electrical load to AC compressor. Yes, directly driving the compressor from the engine is more efficient, but I don't have a place to mount it on the engine. So this is the solution I have. And this is actually lighter and moves the weight of the AC system up front.

I hope all the math works correctly and my father was right. Because I can't go back and ask him any more questions.

The AC compressor of the Chinese made Treelingo $835 AC system referred to above draws 74 amps according to their advert. If that's true, am sorely tempted by it because the "complete system package" seems to include everything needed to add electric AC to a Porsche 914. A 914 has a very small cabin to cool compared to most other cars, even smaller than a Porsche 911. If you change the color of the 914's black roof to something that absorbs less heat, the cheap Treelingo AC system just might work if you add one of the high output alternator systems one of our 914 vendors is selling. The color scheme I am using on my 914 project will have an orange roof panel, instead of black. The more I think about it, the more I am tempted to be the guinea pig who tries out the Treelingo AC system.

Your automotive AC system sees the highest hi side pressures stopped at idle.

The system is the least effective below 1500 rpm with no movement created airflow over the condenser.

On a 110-degree day a 134 system might see 270psi at idle stopped 700rpm.
That same system at 2000rpm and 50 mph will have a high side below 150psi.

That's 3x the RPM but 60% of the pressure. Airflow is EVERYTHING!

A well-designed system might be as low as 120 on the high side and this equates into less HP being required to turn the compressor. Our 06 Odyssey runs like this on stupid hot days.

Now, the point of the highest load for an AC system is also the point of the lowest output from an alternator. Most alternators have a "thermal cut in speed" that you are supposed to be ABOVE to do load (output) tests. This is commonly 1600-2000 RPM.

I believe the reduced output from the alternator at the same time the compressor requires the most energy will be a problem for a 12v compressor. One temporary solution might be excess battery capacity but I am VERY interested in how well Clay's set up will work stuck by the Cresson train for a half hour on a 110 day.

I have recently replaced an interesting condenser. A 2016 Explorer Ecoboost uses two stacked condensers in series to reduce height to allow room for an intercooler.
The thickness of the stacked cores is 2" the width is 27" and the height is 12".
This condenser cooled a BLACK midsized SUV faster than anything else I have tested this season. This critter ROCKS!
It's too wide to fit in a 914 condenser housing but it was cooling a vehicle that has 5-8 times the interior space and it did it fast...
I'm going to try stacking two skinny parallel flow cores together in my housing. I think it will work great.

Stacking condensers.... I never considered that.

The parallel flow condenser I bought to go in the original DPD condenser housing is less than half the thickness of the original condenser coil. But to work properly, it has to have the correct airflow through them.

Maybe I will buy a second one identical to the one I have and stack them.

It's the same Benling DM18A7 compressor I am using. I sold it to him. I was able to buy two of them, one for each of our cars. From Benling it comes with a rotary switch to select 3 different speeds. Low RPM is 40 amps. Medium speed is 60 amps and high speed is 90 amps? Keith and I hardwired our systems to the medium setting, which is more than enough for our cars.

Auto Atlanta sells the factory AC installation guide. I have also seen pirated factory AC pdf's floating around. The manual has all the specs and dimensions. If your running a 914-6 front oil cooler, its easier to put an aftermarket condenser in front of it versus cutting your floor for the dealer 4 banger version.

I went and checked manuals that Jeff has posted on his tech notes and got a couple bits of info but no exact sizing of condenser and evaporator listed.

Updated my earlier post with info on R12 charge and oil capacity which of course would be for those systems with the long hoses.

Thanks for that suggestion!