Vintage Air Wiring Question
#1
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I think I'm going to get the Vintage Air kit for my 72 Cutlass that I'm going to swap an LS1 into. Is anyone, with Vintage Air, using their PCM to help control the A/C or is the A/C system a stand alone system? I'm asking because I'm trimming my wiring harness down and am wondering if I leave in the A/C wiring in PCM connectors. Thanks.
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I am using the pcm to control the vintage air unit in my El Camino, (LS2/4L60E). I have a Speartec harness and there is a wire to hook the compressor lead into it. There were also wires on the harness to connect to the cooling fan relays. PCM has control and will turn the fans on accordingly when high side pressures increase. It retains the factory high side pressure switch that was with the engine i bought. Normal idle drops by 200 rpm when the a/c comes on. I would be happy to answer any questions you have.
Blanchard
Blanchard
#6
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It depends on the ecu. The f body LS1 uses a 12V request sgnal but requires the f body pressure switch be grafted in. On later trucks, etc the request is a data signal.
Just leave it out. Idle is fine. I control 1 fan through the ecu, the other fan is controled by engine temp and/or a trinary switch. VA substituted the trinary for the original binary.
Just leave it out. Idle is fine. I control 1 fan through the ecu, the other fan is controled by engine temp and/or a trinary switch. VA substituted the trinary for the original binary.
#7
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You can wire it to the PCM. If you use the fixed compressor wire it like a truck with the binary switch. If you use the variable compressor use the pressure switch wired like a car. There is no need to spend extra $$$ for a trinary since you can control the fans with the PCM. Typical VA systems use a 12 volt request when the fan turns on and it is a high/low shutoff. From there use the factory diagram for the A/C request. The fans and everything will work properly from there.
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#8
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hooked vintage air stand alone to my 99' ls1 swap 4 years ago. No idle concerns & fans are stand alone also.
It's partly a matter of which compressor used & preference on which route you go.I just prefer keeping them separate.
It's partly a matter of which compressor used & preference on which route you go.I just prefer keeping them separate.
#11
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It depends on the ecu. The f body LS1 uses a 12V request sgnal but requires the f body pressure switch be grafted in. On later trucks, etc the request is a data signal.
Just leave it out. Idle is fine. I control 1 fan through the ecu, the other fan is controled by engine temp and/or a trinary switch. VA substituted the trinary for the original binary.
Just leave it out. Idle is fine. I control 1 fan through the ecu, the other fan is controled by engine temp and/or a trinary switch. VA substituted the trinary for the original binary.
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#12
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The easiest solution would be to splice a trinary switch into the hi or low speed speed wire to the ecu.
If you spice into the low speed, both would be on low any time the trinary switch is closed. High speed would work as it does normally.
If you splice into the hi, only one fan would run at hi speed if engine wasn't hot and the trinary switch closed.
If you spice into the low speed, both would be on low any time the trinary switch is closed. High speed would work as it does normally.
If you splice into the hi, only one fan would run at hi speed if engine wasn't hot and the trinary switch closed.
#13
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Ok just to make sure I understand this. In the trinary switch one of the wires will go connected to the pcm. That wire tells the pcm that the AC is on and it needs the fans on. At that point the computer turns on the fans . Please tell me I got this lol