Air Conditioning on Dry Sump Engine - Rear Pulley or reverse rotation?

[loudandproud]

My engine is cradled into my frame preeeettttyyy tight and AC wasnt originally in the plans. Today it was 91F and like 80% humidity and i got to thinking, man... AC would be nice lol.



Here is the issue. Most AC compressors ive found are too long to be directly mounted in front of the engine and usually have to be mounted around the perimeter of the engine. With the chassis and frame bracing, thats not going to work.

Does any one know of a reverse rotation Automotive AC compressor, or one with a rear mount pulley? The idea would be to machine a bracket and front mount the compressor.

[dontlifttoshift]

Concur with Vimes, you are not the first person with a dry sump and air conditioning.

[Vimes]

Concur with Vimes, you are not the first person with a dry sump and air conditioning.

Dang, and I'd deleted my post to give it a bit more thought. Was suggesting that you (OP) post up what you're working on to see if anyone else has a solution.

But what the hey - I have an electric HVAC compressor solution for you if you're interested. Not for sale, just providing information that took me several years of research to come up with because nobody in the HVAC compressor industry likes posting information about equipment capabilities. It's more expensive and requires a lot more work, but has other advantages like letting you put the compressor anywhere else in the car.

[Richard454]

I too- have a dry sump and no place for an ac compressor.

I wanted power steering and AC - so I went with electric on both.



Here's some food for thought-

-Counterclockwise AC Compressor-Honda "D" series engines run counterclockwise- in pre 2000 Honda 4 cylinders
You can find them really easily.

-Use a standard rotation AC compressor- and mount the alternator backwards- just have to figure the fan cooling the alternator- a common mod done for Corvairs (they spin counterclockwise wise too) and Jag E-Types

- You can run the dry sump pump off the bellhousing - look up circle track cars- and they also have a set up for power steering off the bellhousing-then run alt and compressor off the front.

- or you can use some Lamdo parts- if you really want blow your budget!!!

OR if you want to do an electric AC compressor- look at what they are doing for semi trucks to cool the cabin- thanks to no-idle laws-

That's were I purchased my set up- from a company doing the conversions- Electric cars are also an option- but they need to see 144+ volts- can be done but not cheaply.
Mine pulls about 40A- but I have a beefed up alternator - running a second rectifier externally fan cooled.


Vimes- I love to look over what you've put together- if possible email richard454 at comcast dot net- Thanks

[Vimes]

The DC AC (heh heh) compressors I'm looking at comes in a 12v or 24V version, uses R134a, and produces the same output as a Sanden SD7H15 compressor at just over engine idle. Based on my truck's existing (well, former) air conditioning setup:

Sanden SD7H15 specs
4.0kW / 13.65KBTU / 1.1 tons capacity at 1340RPM compressor speed / 850RPM engine speed
5.0kW / 17.1KBTU / 1.43 tons capacity at 1750RPM compressor speed / 1110RPM engine speed
6.0kW / 20.47KBTU / 1.7 tons capacity at 2250RPM compressor speed / 1428RPM engine speed

These electric compressor units are for systems generating 12,000btu to 17,000btu, or 1 to 1.4 tons, or 3.52kW to 4.98kW of cooling power. This falls within the cooling range of the SD7H15 compressor when running at just off idle. Before I started pulling it apart, my truck had no problems cooling the practically uninsulated cab down at idle on a hot Oklahoma summer day, but just the same when I put it back together it'll be getting both sound and temperature insulation added. All that came with it from the factory was a heavy foam pad on the firewall, under-rug insulation and a few MLV patches at strategic places on metal panels.

I asked the company that makes these about the power draw, and both units draw 720 watts (60a at 12VDC, 30a at 24VDC.) They said that the 100A draw is for the entire cooling unit which includes the blower fan and condenser fan. Just the compressor is 60 amps. And, it's a soft start compressor taking 10 seconds to come up to full speed, so it's not going to shock the electrical system with a sudden 60A draw or go from quiet to RRRRRRRRRRRRRR all of a sudden.

This was some hard to get information. The hardest part was figuring out how much cooling power was actually needed, because every web site I looked at had different claims, with some sites were saying that a car required as much as 40 tons of cooling power, others said the same as a house, ect. Finding the Sanden performance curve chart broke the code for me, and it shows that it needs between 1 and 2 tons of cooling. The compressor can generate up to 6 tons because it's attached to an engine that might run between 800 and 7000RPM, not because it needs 6 tons. I'll add in that this Sanden compressor is used on a LOT of different makes and models. It's also used on Durangos, which have front and rear air, so they can handle cooling a lot of cubic feet at idle speeds. That means the electric compressor should handle largish SUVs as well, although I don't know if they'd handle something like a Suburban.

Oh, and if anyone is curious, I watched a dyno run where a guy ran his car, some mid-90s Japanese sports car, on a dyno. He ran it with the compressor unplugged, and again where it was hard wired on for the run, and it made a 10HP/10TQ across the board reduction having the compressor on vs off. Unfortunately I don't recall if it was a TV show or an internet link, so this is hearsay. Funny thing about that, I had built a plug that would let me do just this but came across the other guy doing the dyno run right before I was going to set up a dyno run of my own.

12VDC version
24VDC version
Sanden SD7H15 performance curve