DaveAZ

1989 SOHC chassis with SR20 swap. Original car had AC. SOHC AC compressor doesn't bolt at all to SR20, nor does Cody Ace make the adapter for it.

(We routinely get temps over 100F, so I don't care if you are a drifter and don't need AC, we do)

So: We got the DOHC compressor and Cody's adapter. This compressor however has single point bolt mounting points for the lines. The stock SOHC lines are double bolted and oh so slightly different in size. So I scrounged around for used lines. I also (tried) to order new lines from Courtesy Nissan. "Parts unavailable."

I modified the existing lines so they should fit, but matching green o-rings for a good seal is very tedious.

I do note that the DOHC compressor is a single wire directly from the AC relay circuit to the clutch. There is no pressure switch wired in series with the clutch circuit. Does that sound correct? No pressure switch protection in these S13 DOHC compressors?

The temp sensor that goes into the stock KA lower radiator hose isn't used on the SR20. Should I use the T-stat we are using to run the electric radiator fans? Or separate relay for the condensor fan? (Concerned about amp draw across the relay if running three fans instead of two)

The AC relay is spliced to the correct wire going to pin 106 on the ECU. This is supposed to function as the ground for the AC relay, once the system is turned on. The F3 plug wire from the dash is also ran to correct pin on SR20 ECU. However, when we jump the pressure switches at receiver dryer, the AC relay does not get a ground. We can manually ground it at the ECU and it does energize, so we know we have the correct wire.

Stupid question: Does the engine have to be running for the ECU to provide the ground to the AC relay?

This has been an uphill battle. I would greatly appreciate any solid help or advice from those who have been there, done that with an almost complete rebuild of their systems.