CLASS RACER FORUM - View Single Post - Yet another MSD crank trigger wiring question

Rob Petrie E395 · 02-13-2024, 04:00 PM

Well I didn’t know the 558-104 harness existed until I just read this. So I have the 558-101 harness and just bought the correct connector for the Iac valve (I also have the adapter from square to flat connectors). But once I got it. I thought it would look bad so I ordered the right connector from Holley. I have the right connectors for the TPS too. But wish I had known this when I was ordering. Uuugghh. I took the first of the 3 Holley classes a while ago. And they really tried to drive the point home about connecting to the battery. I run a battery with top and side terminals. So it’s easier to charge between rounds. So my plan it to run the car off one set of posts. And the ECM main power harness off the other set by itself. One thing other thing told us. Is if you wire the main power harness to the kill switch or somewhere else. And someone hits the kill switch while the car is running or Key on engine off. It can delete the global file. Can you imagine the pain in the rear that could be?

02-13-2024, 04:00 PM	#7
Rob Petrie E395 VIP Member Join Date: Dec 2007 Location: Woodlawn IL Posts: 1,092 Likes: 162 Liked 216 Times in 77 Posts	Re: Yet another MSD crank trigger wiring question Well I didn’t know the 558-104 harness existed until I just read this. So I have the 558-101 harness and just bought the correct connector for the Iac valve (I also have the adapter from square to flat connectors). But once I got it. I thought it would look bad so I ordered the right connector from Holley. I have the right connectors for the TPS too. But wish I had known this when I was ordering. Uuugghh. I took the first of the 3 Holley classes a while ago. And they really tried to drive the point home about connecting to the battery. I run a battery with top and side terminals. So it’s easier to charge between rounds. So my plan it to run the car off one set of posts. And the ECM main power harness off the other set by itself. One thing other thing told us. Is if you wire the main power harness to the kill switch or somewhere else. And someone hits the kill switch while the car is running or Key on engine off. It can delete the global file. Can you imagine the pain in the rear that could be?