1970-Cloned

iTrader: (1)

I have the physical hardware figured out. Lines from the unit to the compressor and the evaporator.

Now I am trying to figure out how to wire it.

How did you guys do it?

I am running a Classic Auto Air system. and a stock corvette AC compressor

On their system you are supposed to run a 12 volt wire to the hi/lo pressure switch and then to the AC compressor.

However my speartech harness already has a plug for the AC compressor and I have a hand off wire from their kit.

Any ideas. Once I get this figured out I plan to post a better explanation of how it was completed.

Jesus Freak

Vintage air trinary switch is how I plan on doing it.

1970-Cloned

iTrader: (1)

After talking with Speartech the wire that comes from their harness inside the cab is a pass through and not connected to the computer.

So I will go out the (blue wire 12V+) to the Binary Switch, From the Binary Switch to the Green Wire on the AC compressor and that will turn the Compressor on. (Black wire off compressor goes to ground)

However after talking with Classic auto air. I need to have a way to turn on the electric cooling fan. I will upgrade the stock binary switch on the dryer to a Trinary switch. According to them once the system hits 240 pressure it will signal the fan to turn on.

They recomended using the Dakota Digital PAC-2700 so that it can control the fans for the engine and the AC compressor.

I think this is the route I am going to go.

Thanks for your help. I hope this helps someone else.

Chicago TDP

iTrader: (3)

Wow, I was told that the stock GM compressors would not work with Vintage air or other aftermarket systems....

downset71

I have a speartech harmess / classic auto air combo also in my 71 monte. The only wire from harness that has anything to do with A/C is a green wire which steps up rpm when ever it see 12V from compressor turn on. Other than that, classic auto air harness is independant. I also wired my second fan to turn on as soon as AC turns on, no matter what line pressure is.

rockytopper

Ditto ^^^ I used a pair of relays to do this. Fans turn on as soon as the a/c request is. You might want to look at the resent thread about converting the VD compressor. It appears to be very simple. I didn't do it but if I every have issues with mine I plan to mod it and get a newer r134 condensor to improve cooling.

1970-Cloned

iTrader: (1)

How did you wire your second fan to turn on as soon as the ac turns on? Are you using that dakota digital controller I was talking about?

1970-Cloned

iTrader: (1)

Several of the techs at Classic Auto air also told me this. At the time I started this restoration and swap there wasn't the option to buy a bracket and put their compressor on the passenger side top.

I believe they want to sell me their compressor. I found one tech there that it will work however the variable compressor may not perform as well as their compressor.

However he stated it should work and be fine. We will give it a shot.

downset71

Simple. Used a relay. Jumped a wire from compressor to the 2nd fan relay. It triggers it and fan turns on. When compressor turns off the fan turns off. Completely independant of primary fan.

69 Ghost

Vintage Air has a schrader valve that mounts to the drier. I turned the threads down to I beleive it was a M10x1.5 so I could put the factory pressure sensor on the car that they use for the variable compresor. The fans and idle will work as stock from there.