Engine swap A/C Compressor

MechMan

MechMan

Greasemonkey
Sep 13, 2018
224
28
Long Island NY
I see that there are 2 options for a A/C compressor for the LS3 and was wondering if one is better to use for swapping into a G body. There is the Sanden SD-7 and the R4.
 
Texas82GP

Texas82GP

Comic Book Super Hero
Supporting Member
Apr 3, 2015
4,867
113
Spring, Texas
The R-4 is much maligned. As you know, we used it on my brother's car. Wha have a window switch wired in that kicks out the compressor clutch above 4k RPM. The car only has about 5k miles on it but so far, so good. We looked into the SD4 and SD7 compressors and decided to keep his Chevrolet all GM.

Edit...I had R4's on several vehicles and always got good service out of them. With the R4 on my brother's car, if we need a compressor in the future, we just buy one for a 91 Camaro so it should be easy to source.
 
MechMan

MechMan

Greasemonkey
Sep 13, 2018
224
28
Long Island NY
The R-4 is much maligned. As you know, we used it on my brother's car. Wha have a window switch wired in that kicks out the compressor clutch above 4k RPM. The car only has about 5k miles on it but so far, so good. We looked into the SD4 and SD7 compressors and decided to keep his Chevrolet all GM.

Edit...I had R4's on several vehicles and always got good service out of them. With the R4 on my brother's car, if we need a compressor in the future, we just buy one for a 91 Camaro so it should be easy to source.
Sound good. I think am going to go a similar route that you guys did with buying the Corvette accessory drive without the AC and buy the Holley bracket. I ask because they offer brackets for both and wasn't sure if one was better than the other for these cars.
 
Texas82GP

Texas82GP

Comic Book Super Hero
Supporting Member
Apr 3, 2015
4,867
113
Spring, Texas
Sound good. I think am going to go a similar route that you guys did with buying the Corvette accessory drive without the AC and buy the Holley bracket. I ask because they offer brackets for both and wasn't sure if one was better than the other for these cars.
Hopefully someone else will chime in with a swap in a G-body and opinions on the compressors. It seems like a lot of the swaps are using truck accessories for budget reasons. Have you looked into some of the other options out there like the brackets from ICT billet to repackage the truck accessories?
 
MechMan

MechMan

Greasemonkey
Sep 13, 2018
224
28
Long Island NY
The water pump and and crank pulley I have are for the Vette configuration and I like the like everything close to the engine.
 
pagrunt

pagrunt

Comic Book Super Hero
Sep 14, 2014
4,017
113
Shelocta, Pa
Would/could the GTO, G8, SS, Caprice, or any LSx power Caddy be other sources for the A/C compressor & brackets? Maybe FWD LSx be another source? Seems like most if not all sources are Camaro, Vette, or trucks.
 
MechMan

MechMan

Greasemonkey
Sep 13, 2018
224
28
Long Island NY
Would/could the GTO, G8, SS, Caprice, or any LSx power Caddy be other sources for the A/C compressor & brackets? Maybe FWD LSx be another source? Seems like most if not all sources are Camaro, Vette, or trucks.
The issue is as far as i know is I need the compressor to be high mounted becaue I do not want to notch the frame.
 
MechMan

MechMan

Greasemonkey
Sep 13, 2018
224
28
Long Island NY
The R-4 is much maligned. As you know, we used it on my brother's car. Wha have a window switch wired in that kicks out the compressor clutch above 4k RPM. The car only has about 5k miles on it but so far, so good. We looked into the SD4 and SD7 compressors and decided to keep his Chevrolet all GM.

Edit...I had R4's on several vehicles and always got good service out of them. With the R4 on my brother's car, if we need a compressor in the future, we just buy one for a 91 Camaro so it should be easy to source.
I am going to have to pick your brain on how you set up the compressor. If i remeber correctly you used the PSI conversion harness righ? Did you get it with the A/C recognition wire?
 
Texas82GP

Texas82GP

Comic Book Super Hero
Supporting Member
Apr 3, 2015
4,867
113
Spring, Texas
I am going to have to pick your brain on how you set up the compressor. If i remeber correctly you used the PSI conversion harness righ? Did you get it with the A/C recognition wire?
We used PSI's HAR-1013 but it did not include the A/C request wire, though it shows it as optional in our instruction book. I don't know if we missed that or if the guys at PSI decided we didn't need it. They custom made the harness since we had LS3 injectors (L96 Gen IV engine with Gen III PCM and DBC throttle body.

We used Vintage Air for the HVAC case, controller and condenser. Their 'perfect fit' kit, less compressor and lines included a wiring harness, which we integrated into the car and modified with the window switch/relay setup to kick out the clutch above 4k.

I should be able to answer any questions on what/how we did it because all the research/wiring diagrams/notes are all together at the house.

It might be easier to tune if you can use the A/C recognition wire but our tuner did a great job. I'm guessing with an IAC and a command RPM, the PCM can control the varying load on the engine with the compressor clutch cycling in and out.

Are you running DBC or DBW throttle body?

Check out the other options out there on accessory brackets. Many, including the ICT Billet can handle all of the various offsets of the production balancers. Still, if you want all new stuff, it might be hard to beat a production accessory drive like the one for the C6 Vette that we used. I'm just saying there is a lot more out there than there was in 2012 when we were making these decisions.

HTH,

Jared
 
MechMan

MechMan

Greasemonkey
Sep 13, 2018
224
28
Long Island NY
We used PSI's HAR-1013 but it did not include the A/C request wire, though it shows it as optional in our instruction book. I don't know if we missed that or if the guys at PSI decided we didn't need it. They custom made the harness since we had LS3 injectors (L96 Gen IV engine with Gen III PCM and DBC throttle body.

We used Vintage Air for the HVAC case, controller and condenser. Their 'perfect fit' kit, less compressor and lines included a wiring harness, which we integrated into the car and modified with the window switch/relay setup to kick out the clutch above 4k.

I should be able to answer any questions on what/how we did it because all the research/wiring diagrams/notes are all together at the house.

It might be easier to tune if you can use the A/C recognition wire but our tuner did a great job. I'm guessing with an IAC and a command RPM, the PCM can control the varying load on the engine with the compressor clutch cycling in and out.

Are you running DBC or DBW throttle body?

Check out the other options out there on accessory brackets. Many, including the ICT Billet can handle all of the various offsets of the production balancers. Still, if you want all new stuff, it might be hard to beat a production accessory drive like the one for the C6 Vette that we used. I'm just saying there is a lot more out there than there was in 2012 when we were making these decisions.

HTH,

Jared
I will be running Drive by Cable. I am looking at the PSI HAR-1059 harness since I am looking to run a manual transmission.
 

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