69Stanger408 82 Report post Posted September 10, 2019 Making some final electrical connections and stuck at the WOT relay switch. This newly installed relay will shut down the compressor at wide open throttle via a ground trigger from the Holley ECU. I believe the activation wire would be the light blue that goes to the trinary switch and then onto the compressor, however I am unsure. The Holley techs call it the "AC Activation Wire" Additional pin out for this relay is pin 86 battery power, pin 87A from pin 86 of existing vintage air relay #86 (which is breaker power), and pin 30 which is the AC Activation wire... Assistance appreciated. Quote Share this post Link to post Share on other sites
Vicfreg 771 Report post Posted September 10, 2019 Quote Share this post Link to post Share on other sites
Vicfreg 771 Report post Posted September 10, 2019 I would install the relay in the wire going to the compressor, not the way Holley recommended it. I advise checking with Vintage Air to see how they usually use a WOT interface with their system. Putting in series with the Binary/Trinary safety switch is what I would do, but they for sure have dealt with this before. 1 69Stanger408 reacted to this Quote Share this post Link to post Share on other sites
69Stanger408 82 Report post Posted September 10, 2019 Checked with Vintage Air (VA) and they recommend the following for the Gen IV system: For the idle / RPM increase when AC is activated, tap the existing blue wire on Pin 85 of the VA relay with the orange wire (ground input #1 -) from Holley Sniper. This will signal the ECU that the AC clutch is activated and increase RPM to assist with compressor load. For compressor shutdown at wide open throttle (WOT), you require a new 5 pin relay, wire as follows - Pin 86 Holley gray wire (output #6 -), pin 30 battery, pin 85 keyed 12v, and pin 87 is a tap from Vintage Air orange wire off the ECU that goes to an existing VA WOT switch. Little different than Holleys explanation and reduces the installation of two replays to one. Quote Share this post Link to post Share on other sites
Vicfreg 771 Report post Posted September 14, 2019 Oh, good stuff. I like the RPM increase on compressor start. I have to look into that with my FiTech. Quote Share this post Link to post Share on other sites
69Stanger408 82 Report post Posted September 14, 2019 1 hour ago, Vicfreg said: Oh, good stuff. I like the RPM increase on compressor start. I have to look into that with my FiTech. The compressor, when activated decreases RPM by ~200. Quote Share this post Link to post Share on other sites
Vicfreg 771 Report post Posted September 15, 2019 Hmm. I figured it would increase the RPM by 200 when the compressor starts. Quote Share this post Link to post Share on other sites
69Stanger408 82 Report post Posted September 20, 2019 Yes, increase Quote Share this post Link to post Share on other sites