Air Conditioning
 

About to hook up the A/C on my LS6 RX-7. Just trying to get some ideas on the best way to do it. Should I use the RX-7's A/C system and plumb it to the LS's compressor, or use all GM stuff. Any advice is well appreciated.

The only mazda thing I used in the entire A/C system was the evaporator core. Everything from the fittings on the firewall forward I made and used GM parts. There's a write-up on norotors that covers it pretty well. Thats the guide I followed.

That's what I'm considering doing, using all GM stuff from firewall forward. I'm not using the stock ECU, however, so I don't know if that will affect which parts I use. The refrigerant pressure switch is one of those parts. So I need some info on building an A/C system that doesn't require the use of the GM ECU.
Thanks

The pressure switch does nothing more than protect the compressor if the pressure is low. You can hook up a 12v power signal to the clutch and engage it with nothing more than a switch and a battery.

Many aftermarket ecu's like the Holley dominator could even control the A/C with an RPM cutoff and everything.

The Mazda Evap is all you'll use. A condenser from ebay and a dryer are fine. It's the lines that need to be custom made. Halfspec on norotor has done a ton for use.

Sounds good. Thanks for the info. I'm running the Electromotive TEC GT ECU. I'm not sure if that has the ability to control A/C function but it sounds like I won't need it to.

Contact Halfspec he's selling complete AC kits with controllers for LS FD. He's also on the norotor forums.

agreed.
I've got one of his kits fully working

Not true. The LS1 uses a pressure sensor, not a pressure switch. The pressures sensor is wired into the PCM so the PCM can measure pressure value which is part of the complete AC control system. Using the PCM to control your compressor will change your idle parameters when the AC is on so that you don't bog down at red lights. It will turn your fans if your freon gets to a certain pressure (editable pressure value via HPTuners or the like). Freon temperature is directly proportional to freon pressure, so the PCM will know if your condenser is too hot. It will also turn your compressor off at WOT and at 5200RPMs, since the compressor isn't rated at much higher than that. You will literally compress your compressor to pieces if it is sustained at much higher RPMs. I know.

I highly recommend to include the GM sensor in your AC build. You wan't your car build right, don't you?

Not sure if the pressure sensor is compatible with the electromotive ecu. The ecu will idle up with A/C on but not sure it will recognize signal from sensor. Wondering if switch will be ok.