Im reusing the 4th gen fuse block on my 90 Iroc. Do I use the ignition and starter relays from the 4th gen or does my car already have them?

 

My car didn't have them, neither does the '92 to the best of my knowledge.

I wired in the start relay circuit because I was getting too much voltage drop through the connections/switches when the purple 3rd gen wire was hooked directly to the starter solenoid.

 

If you are using the 4th gen LS1 fuse/relay/power distribution blocks, you dont need ANYTHING from the old car as far as relays are concerned. You feed the big pink wire (hot in run AND crank) from our C100 to the IGN relay, give it battery voltage, hook up the grounds, run power back to the fuel pump, plug everything in and it'll run.

There is a lot of cleaning up you can do with the blocks, including combining them into one. I didnt do that, I just deleted wires that I didnt need, left a few fuses in there for accesories, and mounted them as is.

Im convinced this is one of the cleaner and easier ways to hook up an LS1 if you dont mind seeing the fuse blocks or get creative with hiding them. Heck you dont HAVE to delete wires if you dont want to...but there are a lot of them that can go.

I think I have 3-4 original wires coming from my c100 on the one side. The rest are gone.

J.