A/C help needed

I looked and I can't find that picture. I thought it was in Admin's or Vorsche944's gallery but it wasn't.

Anthro, I think this type of downward-pointing adaptor block:

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along with the 90 degree Long Shank hose fittings here:

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would probably have the fittings reach down and under the compressor.

I took some measurements (with some difficulty, man that car is low to the ground!) and it looks tight but maybe doable.

What do you think?

Edit: Or maybe it would be easier to simply get an adapter block that points upward and bring the fittings over the top of the compressor and down to the block...

It might, I will take some measurements tomorrow. I just hung mine this afternoon. I know I have seen one that had factory looking lines out of the compressor.

It looks like that would work. Good find. The aluminum tubes are bendable so you might not even need the intermediate elbows. The fewer the joints the better.

Arthropraxis wrote:It looks like that would work. Good find. The aluminum tubes are bendable so you might not even need the intermediate elbows. The fewer the joints the better.

I'll order some parts and see how they fit.

Anthro, I took my car to an AC shop today that was recommended to me for some advice and they liked the flat adaptor block.

However they suggested the fittings/pipes/hoses would be best supported by running them along the passenger side frame rail and then behind/under/whatever the radiator over to the condenser and the AC vacuum line. That way everything could be hard mounted to something and supported better.

The guy suggested one line might be better going under the compressor while the other went over top of it.

They didn't have a open lift when I was there so they couldn't get under the car to see better, but this is what they suggested just from looking in the engine bay.

I'll try to get in there again later this week.

You'd think this had already been done before enough times such that the best options for AC hoses, fittings and routings would be outlined somewhere?

In Bridar's gallery he has his done about like that one under the other under the compressor. He has one line going back to the firewall and the other routed as you describe. Some have the return line going up over the passenger side fender to the firewall. The way you have them described is how I want to do mine.

Cool, I need to study Bridars's pics more.

Does it look like Bridar used an adaptor that sent each line in opposite directions? ie, the vacuum line up and over the compressor but the liquid line down and underneath?

I can get you some pics of what I did, I ran the suction line down along the passenger frame to the compressor. Compressor output was run along behind the bottom of the radiator to the condenser. I used the stock Porsche lines from the drier back to the evaporator. At the compressor, I used an aluminum adaptor block. I made the lines with beadlock crimp connectors.

Hard to tell from the pics and my limited knowledge. I like the idea of going around front and hooking up to the factory lines. Aeroquip has lines you can make yourself or coldhose.com will custom make lines to your specs.

My LS1 swap is my second project with AC, on the other project (V6 MGB) I purchased the required fittings and some lengths of hose. I then mocked up the hose runs and placed masking tape around the hose and fittings at each joint. I the wrote on the tape a number for the joint and a line to key the hose to the fitting.

I then disassembled everything and took it to my local NAPA store where they crimped all the joints using the key info to align the hoses and fittings.

I plan to do the same with the 948 except I will use two existing hoses from the firewall to the dryer and dryer to the condenser.

New hoses are required from the compressor to the firewall and from the condenser to the compressor.
This second hose will run across the front of the car.

Here's some pics, the cylinder with blue ends is an inline filter with compression fittings.
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Thanks guys, great stuff. I PM'd Bridar and he said he used the stock 2002 Camaro A/C manifold and modded the lines and hoses. I'm not familiar with that stock manifold but I guess it sends the vacuum and liquid lines in opposite directions when they exit the compressor, one up and over and one down and under.

That is what I have, IIRC. Mine does send them in different directions. I will try to get some pictures for you.

Acorad,
This pic from the GM parts book might help your understanding of the part I used. The part in question is labeled #1 in the pic. it is a complete adaptor/tube/hose assy for both compressor inlet and outlet hoses. On the Camaro they direct both lines to the front of the car. For the 944/968 we don't have that much room under the hood, so the evaporator to compressor line has to go straight up from the rear of the compressor. The GM part (P/N 10409630, if you want to go the junk-yard route) simply served as a good starting point. You can also get the compressor adaptor blocks from docsblocks.com or coldhose.com. Sorry I couldn't get the image to display any larger. Hopefully all can view teh detail ok.
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Thanks Bridar, that really helps, I was looking for a good diagram of the Camaro A/C system but couldn't find one.

fwiw, I was googling around and read that the low pressure hose from the evaporator to the compressor should be at a slight down-slope to the compressor and that there should not be any "U's" in its hoses/hard lines that would trap the AC oil.

Which I guess makes sense, in that that low pressure line is vapor and the oil in that line is a liquid so that there's nothing really to "push" the liquid oil along. Therefor it would probably be better to run that hose/line downhill so the oil can be pulled by gravity down to the compressor, and that it would probably pool if there's a low point along the way, like in any "U" shaped hose/line areas.

This would mean my planned route of bringing the low pressure hose from the hard line's stock location on the driver's side fender to down under the radiator and then up to the compressor probably isn't the best solution, AC-wise.

It would seem a straight shot from the passenger side firewall bulkhead down to the passenger side compressor as many here have done would be the better AC option.

Im not sure who or where that information came from, but i know for a fact that Porsche breaks this rule, as well as any bus style a/c system. And in school there was never anything that indicated that was necessary, the oil is carried through the system with the refrigerant. I would build your system the way you want to.

Mark

Thanks Mark, I appreciate that. I guess I should have started with something like "I just googled around and read this, does this make sense to you guys?" I really was not looking forward to redoing the work that's already been done on my AC.

edit: And, now that I looked at it, the low pressure line on my Durango comes from way down low on the firewall, comes up, does a full loop-de-loop and then ends at the top of the engine at the compressor. So it also doesn't go downhill from the evap to the compressor, it goes steeply uphill. Thanks again Mark.

Acorad, did you ever get your A/C system set up?

Arthropraxis wrote:Acorad, did you ever get your A/C system set up?

Thanks for the note Anthro.

The answer is no, not yet. I've been super busy and also have been dealing with other gremlins - CV joints, cooling fan, radiator, etc. And it hasn't been all that hot yet. I should have more time after the first weekend in June.

How are you coming on your A/C?

Well, I bought a F-body ECM to have AC request then found out it won't work with the wiring on the GTO harness's O2 sensors. Now I am trying to nail down if I can get another program to run A/C request off of the GTO ECM. I really don't even need to have the computer associated with the A/C as it turns out, but it would be nice to have idle up and the high speed fan with the A/C on.

The other benefit for letting the GM computer control things is the pressure sensor, and RPM, after about 4K (programable) the compressor is turned off, and if pressure is not right things are shut down. I am determined to make this work, but the darn GTO ECM is a real PITA!

Ok, so it looks like the heat here in CA is going to stay awile and I need to get going on this AC.

The GM compressor has been in place for severaly thousand miles, but the orifices have been open as there was no fitting on them.

I assume the compressor has a bunch of road grit in it, any idea of how I go about cleaning out the compressor? Brake cleaner?

Edit: OK, it looks like a good flush is what the entire system needs.