Connecting LS A/C to Factory Air - The 1947 - Present Chevrolet & GMC Truck Message Board Network

lts70 · 07-02-2021, 10:13 AM

We finally got the LS bolted into my boys 1968. Wondering if anyone has any pictures of how they connected the LS low mount compressor to the original AC system. May have to clearance my frame a little bit but I’m OK with that . Hoping to get some ideas r pictures from those that have been successful with this.

Davidf · 07-02-2021, 10:36 AM

Don't have much time to respond...heading for vacation soon. Anyway, I did a combination of Cold Hose extension pipes...converts to o-ring fittings straight to the front (did this for high side). For low side, I took the donor hose, cut the end off and welded a #12 nut to the pipe. So, the block compressor fitting comes straight up off the compressor and a straight 0-ring barb fitting connects to the compressor fitting (I converted my factory POA system to an orifice tube system). Had to slightly clearance frame for the low side pipe to clear.

Hope this makes sense.

https://coldhose.com/products/gm-5-3...35532197494944

ls1nova71 · 07-03-2021, 09:58 PM

If you can TIG, then it becomes pretty easy to do. If you can't, then you need to find someone who can, then its still pretty easy. You get the factory low side fitting and TIG a barb fitting on it, then you can crimp the hose on it. For the high side, if you can find a 99-07 GM SUV in the junk yard, you can snag the upper condenser line off it, and it will bolt to the high side of the compressor, but will come straight out the front so you don't need to notch the hell out of the frame. You will also have to weld a barb fitting on this than crimp on your hoses. There's pics in my build thread on LS1Tech, there's a link in my signature, the rusty one, not the blue one.

lts70 · 07-04-2021, 10:06 AM

Thanks for the response guys. I injoyed looking through your build thread you are very talented!

I think these are the pictures you were referring to

ls1nova71 · 07-04-2021, 06:44 PM

Yes, but that was the first attempt, however the high side was too small. I switched it out to the Tahoe condenser fitting and it comes out the front rather than looping around the low side hose like that one did. Post #262 has pics of the new line.

Edit: Apparently my memory is slipping, but I guess I made that whole line on the green truck, but on the yellow truck thread I have pics of the Tahoe condenser fitting. Post #202 https://ls1tech.com/forums/conversio...-build-11.html

lts70 · 03-10-2022, 04:47 PM

Thanks for the examples ls1nova71, I have the weld on barb fittings ordered and I am hoping to get a set worked up for my boys truck like yours.

What condenser and evaporator are you using? Is there one that fits in the stock AC box?

07-03-2021, 09:58 PM	#3
ls1nova71 Registered User Join Date: Dec 2009 Location: Independence Mo Posts: 4,119	Re: Connecting LS A/C to Factory Air If you can TIG, then it becomes pretty easy to do. If you can't, then you need to find someone who can, then its still pretty easy. You get the factory low side fitting and TIG a barb fitting on it, then you can crimp the hose on it. For the high side, if you can find a 99-07 GM SUV in the junk yard, you can snag the upper condenser line off it, and it will bolt to the high side of the compressor, but will come straight out the front so you don't need to notch the hell out of the frame. You will also have to weld a barb fitting on this than crimp on your hoses. There's pics in my build thread on LS1Tech, there's a link in my signature, the rusty one, not the blue one. __________________ My '72 short bed build. http://www.ls1tech.com/forums/conver...6-0-4l80e.html 5.3 swap into my RUSTY '71 C10 http://ls1tech.com/forums/conversion...71-c-10-a.html

07-04-2021, 10:06 AM	#4
lts70 1970 Daily Driver Join Date: Jun 2007 Location: Glenns Ferry IDAHO Posts: 1,038	Re: Connecting LS A/C to Factory Air Thanks for the response guys. I injoyed looking through your build thread you are very talented! I think these are the pictures you were referring to Attached Images __________________ It's not truly yours if you didn't build it yourself or if you don't do your own maintenance.

07-04-2021, 06:44 PM	#5
ls1nova71 Registered User Join Date: Dec 2009 Location: Independence Mo Posts: 4,119	Re: Connecting LS A/C to Factory Air Yes, but that was the first attempt, however the high side was too small. I switched it out to the Tahoe condenser fitting and it comes out the front rather than looping around the low side hose like that one did. Post #262 has pics of the new line. Edit: Apparently my memory is slipping, but I guess I made that whole line on the green truck, but on the yellow truck thread I have pics of the Tahoe condenser fitting. Post #202 https://ls1tech.com/forums/conversio...-build-11.html __________________ My '72 short bed build. http://www.ls1tech.com/forums/conver...6-0-4l80e.html 5.3 swap into my RUSTY '71 C10 http://ls1tech.com/forums/conversion...71-c-10-a.html Last edited by ls1nova71; 07-04-2021 at 06:58 PM.

03-10-2022, 04:47 PM	#6
lts70 1970 Daily Driver Join Date: Jun 2007 Location: Glenns Ferry IDAHO Posts: 1,038	Re: Connecting LS A/C to Factory Air Thanks for the examples ls1nova71, I have the weld on barb fittings ordered and I am hoping to get a set worked up for my boys truck like yours. What condenser and evaporator are you using? Is there one that fits in the stock AC box? __________________ It's not truly yours if you didn't build it yourself or if you don't do your own maintenance.

07-02-2021, 10:13 AM	#1
lts70 1970 Daily Driver Join Date: Jun 2007 Location: Glenns Ferry IDAHO Posts: 1,038	Connecting LS A/C to Factory Air We finally got the LS bolted into my boys 1968. Wondering if anyone has any pictures of how they connected the LS low mount compressor to the original AC system. May have to clearance my frame a little bit but I’m OK with that . Hoping to get some ideas r pictures from those that have been successful with this. Attached Images __________________ It's not truly yours if you didn't build it yourself or if you don't do your own maintenance.

07-02-2021, 10:36 AM	#2
Davidf Registered User Join Date: Nov 2014 Location: Austin Posts: 749	Re: Connecting LS A/C to Factory Air Don't have much time to respond...heading for vacation soon. Anyway, I did a combination of Cold Hose extension pipes...converts to o-ring fittings straight to the front (did this for high side). For low side, I took the donor hose, cut the end off and welded a #12 nut to the pipe. So, the block compressor fitting comes straight up off the compressor and a straight 0-ring barb fitting connects to the compressor fitting (I converted my factory POA system to an orifice tube system). Had to slightly clearance frame for the low side pipe to clear. Hope this makes sense. https://coldhose.com/products/gm-5-3...35532197494944



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