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Good afternoon all, I thought I would create a post for my attempt to mount the LS3 computer and the additional wiring blocks so here is the first set of pictures. I had the body on and set this up quite a bit to find the best spot. My car does not have air-conditioning so that gives me quite a bit more space in this area. I centered it front to back between the heater box and overflow tank.
I have a fuse block that is wired into the LS three harness and an additional one I got from a GM truck for the fan control. If I had to do it all over I would wire up my own fan control wiring.
Yes that's about the same distance away from the exhaust that GMH put them in the Commodore and GTO . But they put a substantial heat shield across the ECU as well.
Yes that's about the same distance away from the exhaust that GMH put them in the Commodore and GTO . But they put a substantial heat shield across the ECU as well.
Thanks. I agree it needs a heat shield, that is part of the fitting process, once I make sure this is in the right place I plan on fabricating a heat shield for it.
Here's a really inexpensive way to save you a bunch of headaches in troubleshooting-
Fuses with a LED - that lights when they are blown
Thanks, I saw they have those at Tractor Supply, I was going to see how the access was on these once the body was back on and perhaps swap to those if I cannot see them easily.
Further progress - I ran a 12 gauge wire from the alternator to the new fuse block which will also tie to the starter lug. The only issue I have so far is that the six pin plug to the throttlebody just barely connects and so I think I will get an extension for it from Summit.
Yes , plenty of things to adjust when you put an engine in a car not designed to have it.
Just looking at your fuel line , maybe think about leaving the steel line as is , until you get the body on , then bend it up to make it come up across the fire wall to get the end up where the fuel rail is , then its straight across the top of the motor avoiding those exhaust manifolds completely , that's how I did my LS1 swap . I managed to use the original Commodore(GTO) flexi line to the fuel rail as well.
Looks good but mount the ECU so it's not grounded to the bracket.
Any advice on the best way to do that? I have some rubber mounts I plan on using between the bracket and ECU, but it will still be grounded via the bolts as I currently have it.
Have you thought about how youre going to access any of that stuff once the body is on?
It will be tight to get to but the heater box still comes off and you can reach everything, may need a mirror to see some of it. I did install the fused that glow when the blow so that will make it easier to find them if needed.
Any advice on the best way to do that? I have some rubber mounts I plan on using between the bracket and ECU, but it will still be grounded via the bolts as I currently have it.
Maybe use a factory plastic mounting bracket?
You definitely don't want the EFI harness grounded by the wiring to the engine and the ECU case grounded to the body or frame
When I did my LS1 swap I mounted the ECM and the relays on the back side of the right wheel well. Used a "stock" LS1 ECM holder and made a bracket to hold the ECM and a bracket for the relays. Did not rubber mount it. It was more less covered up by the top of the fender. It was far away from the exhaust manifolds.
Grounds. I run a heavy ground wire from the battery to the frame, Heavy gauge wire frame to engine block (actually two from the frame to engine). Can't have too many good grounds. I don't what engine harness you are using but on all the LS harness's I've used have ground wires that bolt to the engine block.
I don't mean to trash your vertical bracket design but I would not have welded it solidly to the frame. You are going to hate it if for some reason its in the way and you can't move it out of the way. My .02 bolt or weld "L" bracket to the frame and then bolt your vertical bracket to the "L" bracket.
Flat statement.....electronics DONT LIKE HEAT, no matter the source.......and I don't give a **** WHAT any 'factory' designers do with their products.......planned failure anyone???
ALL electronis belong inside the passenger area, maybe under the dash somewhere.....I buried my compuer under/behind and map pocket in my '72.......
When I did my LS1 swap I mounted the ECM and the relays on the back side of the right wheel well. Used a "stock" LS1 ECM holder and made a bracket to hold the ECM and a bracket for the relays. Did not rubber mount it. It was more less covered up by the top of the fender. It was far away from the exhaust manifolds.
Grounds. I run a heavy ground wire from the battery to the frame, Heavy gauge wire frame to engine block (actually two from the frame to engine). Can't have too many good grounds. I don't what engine harness you are using but on all the LS harness's I've used have ground wires that bolt to the engine block.
I don't mean to trash your vertical bracket design but I would not have welded it solidly to the frame. You are going to hate it if for some reason its in the way and you can't move it out of the way. My .02 bolt or weld "L" bracket to the frame and then bolt your vertical bracket to the "L" bracket.
Thanks. I will see if I can move the ECU over to the wheel well, the rest can stay where it is with a heat shield behind it. I will also plan on making the bracket removable, was going to do that but took the easy route.
Flat statement.....electronics DONT LIKE HEAT, no matter the source.......and I don't give a **** WHAT any 'factory' designers do with their products.......planned failure anyone???
ALL electronis belong inside the passenger area, maybe under the dash somewhere.....I buried my compuer under/behind and map pocket in my '72.......
How did you get it to reach? I am using a stock harness and it would be about 2 feet short for that.
All the LS1-LS3 ECMs are in the engine compartment. Relays as well. But the relays are in a plastic box near the firewall.
Just went and looked my 15 Silverado with a 6.2, I know its not a gen 4 LS but the ECM is mounted to the firewall. Not further protection from the elements.
With the right connections to the relays they are water proof as are the ECM.
LS3 conversion - Mounting ECU
