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Discussion Starter #1
Ok, some of you might call me crazy...but I am so here goes. I want to convert my AC lines to AN fittings. Reason being that I need the lines in the front to be flexible to be able to clear my intercooler. I already bent the hell out of the stock lines and I'm afraid if I bend them anymore they are just gonna crack in half.

I know standard SS lines with rubber inner hoses will prob seep out the refigerant over time since those hoses are a bit porous. But the Teflon lined SS lines should be ok. I mean they use that stuff to flow nitrous and for brake lines which are about 1000psi or more. Anyways, my question is if the AN fitting can hold that kind of pressure without leaking.
 

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Virgin Magnet
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i'm sure it would hold the pressure, but can you do it without it leaking? that would be my concern, the next concern is how are you going to adapt the fittings, there are funky connection systems in all the lines, all will have to e modified to NPT then to AN i would think
 

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Hahha...I just went through all this! Actually, I procrastinated since I finished my swap until now.

Exhibit 1:


I inset my intercooler a bit and that caused the interference issue w/ the A/C line right there. I attempted to weld it into a right angle manifold. I rewelded at least 3x trying to get the smallest of pinhole leaks out of the system. Not really even a pinhole...I'm talking about losing about 1psi vacuum in a hole day.

But anyways...resorted to buying a new line cause I just couldn't keep the porosity out of it. I've found that I can take the bottom of the condenser an d inset it more against the radiator to just buy me enough clearance. There is a rubber bracket thing at the bottom of the condensor. Simply reworked it so I can screw the front edge of the condensor to the back edge of the clip.

Good luck as AL A/C lines are a bitch. Could never find the right brazing compound.

Just changed to a new line yesterday and I'm vacuum testing it now. I should be all charged and ready to go tonight.
 

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Virgin Magnet
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wow, that tubing is not easy to weld.. any reason why not to just npt thread the hole and use a NPT-AN adapter?
 

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I think it would be a bad move. How you are going to get the service port in with the lines?
 

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wow, that tubing is not easy to weld.. any reason why not to just npt thread the hole and use a NPT-AN adapter?
I never really considered using fittings other than the stock stuff. Also, I couldn't thread anything and guarantee that no contaminates get into the system. The A/C system is particularly sensitive about it.

That stuff is really thin and challenging to weld. I was able to weld it but I guess the AL filler I have is not high enough grade to avoid slight porosity or the base metal is infused with A/C oils.
 

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Virgin Magnet
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different filler wouldn't do much for the oils, youwould need to do a vapor degrease or some sort of chem cleaner for oils, slight porosity isn't a big deal in something liek that, th weld is thicker than the material , no big deal for strength. leaking i doubt there will be a problem.
 

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I tried my best to brush and clean with acetone...even soaking the fitting in it. I was able to weld and get nice puddles. However, everytime, there would be a very very slight leak somewhere in the join. To the point that I have to leave it for at least 10 min before I can see signs of UV leak detector. I have read that there are diff grades of filler and higher grades are needed for these types of joins. Not really a strength issue, just a purity/contamination issue.
 

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Just something to remember...Its not good to leave the a/c system open for extended periods of time especially if you have R134a...You want to avoid getting moisture into the system by plugging the lines...Moisture breaks down the refrigerant oil into acid and eventually you will develop a hole in your evaporater...
 

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I am glad I have a local CNC machine guy nearby.. Under many occasions, whenever I had to reroute AC lines, I get my CNC guy to machine me an adapter that still bolts right up to the stock connections but converts to an -AN style fittings for me to run new lines. No welding necessary. I rarely use SS braided hoses but rather thick aluminum hard tubing from Summit.
 

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Just something to remember...Its not good to leave the a/c system open for extended periods of time especially if you have R134a...You want to avoid getting moisture into the system by plugging the lines...Moisture breaks down the refrigerant oil into acid and eventually you will develop a hole in your evaporater...
Uh if the lines were disconnected that means all the refrigerant is gone. Which means that you will have to reservice the AC. In a AC service it consist of vacuum pumping all the moisture and air then refill.
 

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I just never take mines out. When take out my engine (twice) i never take out the a/c compressor.
 

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Discussion Starter #13
I am glad I have a local CNC machine guy nearby.. Under many occasions, whenever I had to reroute AC lines, I get my CNC guy to machine me an adapter that still bolts right up to the stock connections but converts to an -AN style fittings for me to run new lines. No welding necessary. I rarely use SS braided hoses but rather thick aluminum hard tubing from Summit.
Ok, so you do run AN lines for the AC system then? Good, I just wanted to know that it's possible. I have a friend that owns a high precision machine shop so this conversion won't be a problem. I just wanted to make sure the AN fittings and all could hold without leaking.
 

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Must have one crazy intercooler setup because my shit is huge and everything fits just fine.
 

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How thick are your I/Cs?
 

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How thick are your I/Cs?
My intercooler is wide, so I was forced to mount it closer to the condensor... My IS300 in particular didn't need to do anything with the AC lines though. It was on other cars that I've worked on needing some attention to the AC lines.

The -AN fittings and connections themselves can be used for AC.... but I didn't use braided hoses for the pressure side. I used thick gauge aluminum tubing from SummitRacing and flared connections most of the time.
 

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Ah... I have my crash bar in as well and my I/C is 3.5" thick.

So for those of you in the future that want to go thick/wide I/C's...keep an eye out for the lower fluid line. Like I said earlier, you can inset the condensor a bit to buy another 1/2" clearance. Or hang it forward and trim the bumper.
 

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^ Nice find!
 
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