Hanz12

Alright, I am trying to wire up my ls swap and I have become a little overwhelmed with it and need some help. This is my first time wiring an engine so I'm sorry if these are dumb questions, I have tried to read as much stuff on wiring here as I can but it still confuses the crap out of me. Some background info. Engine is out of a 2000 camaro ss m6. Wiring harness is from an 01 2wd 5.3 truck with ac and cruise. Car it is going in is an 87 IROC. I've got the harness all torn apart and individual connectors separated out with most of the pcm terminals labeled already. My main question is how and where to fuse all of the connections that came off of the underhood fuse block. I would really like to use the stock third gen fuse block but if it makes it much simpler I have the 4th gen engine bay fuse box I can use. (Not sure if they are the same connector between 00 f-body and 01 truck)
My second concern is how it connects with the under dash connections and what I actually need. I am planning on putting in the 4th gen gauge cluster like a couple members have done so I am wondering what connectors to splice in or not.
Third question, an I close to correct assuming the only part of the third gen engine bay harness I need is the C100 plus whichever dash connectors?

Thank you for any help you can give me. I was truly overwhelmed yesterday and didn't know what to do next with this so hopefully you guys can help me get unstuck.

Pocket

iTrader: (24)

The c100, c207, c221, hvac connectors and fuel pimp fuse are all the 3rd gen bits to retain. Most of the fuse points are in the c207 and c221. See the pinout for 87 in the additional info thread in the sticky

Hanz12

Thanks Pocket, it seems to make sense now.

Hanz12

Alright a couple more wiring questions here. Hopefully someone can help me out. same project as the first post. trying to finish up the harness and have everything pinned for engine, what I am wondering is about the AC connections. the AC for TPI had the Compressor clutch running on the C100 and the pressure switch running on the HVAC harness which connects with C100 I believe. my question is for the LS1 harness all the AC components have computer pins, where would those connect up on the thirdgen, meaning from C100 to PCM? is there a connector that I missed somewhere that those plug into? the pins for the LS1 I am referring to are: B45, R14, R17, R18, and R43

I hope my question made sense, any help is greatly appreciated!!!

Pocket

iTrader: (24)

3rd gen and ls1 Ac wiring are totally different

When using the 3rd gen compressor I mimick the TBI diagram (austinthirdgen) which is completely independent of the PCM

Fbody low mount is a bit more involved. First, you need a relay and trinary pressure switch on the high pressure line. The trinary switch is completely PCM controlled. The PCM triggers the relay which engages the compressor. The compressor wire on the PCM is a feedback pin to know the compressor did kick on when commanded. From the 3rd gen hvac connector, lt blu is Ac request and goes directly to the PCM

Follow?
There's a good diagram in a ls1 Ac thread fairly recent

Hanz12

Ya it is starting to make a little sense. I've got a full ls1 a.c. setup going (compressor, evap, drier, lines) so I will need to add a relay for the compressor clutch wire? And then a.c. request goes into the hvac harness(lt blue wire) from pcm? Then just run the pressure switch from the ls1 to the pcm and it should work.
I found a diagram on here somewhere I'll have to post later when I'm not on my phone but that has helped a bit.

Edit: Attached is the diagram I have been looking at (thank you to who posted it), I think it might be using third gen AC components though.

Hanz12

Another question. 87 C207 pin G GAGES fused power. anyone know what that is to? and what kind of power does it get? IGN or BATT?

Hanz12

So doing some looking at the Gages fuse on the C207 and it is hot in run power, does the power need run to it or is power coming from the fuse? can I connect this into the IGN common if it needs powered? or does it need it's own power wire run from somewhere? I see on the original TPI wiring the ECM is connected to it so that confuses me some too. someone please help me!!!

Pocket

iTrader: (24)

The diagram posted is for LS1 low mount AC. Its missing the AC request wire, which is from the 3rd gen HVAC connector (lt blu)

The gages fuse wire is strange, I dont recall ever using it. Unplug the C207 and turn the IGN on, if the pin has 12v on the dash side, it is not needed for the conversion. I dont recall the gauges getting 12v from the engine harness though, but older cars do supply ground for the gauges on the C207

Hanz12

Thanks Pocket.
could the Gages fuse be supplying power to emissions for that year? while I was looking at the diagram on Austin thirdgen I noticed ECM, EGR, Air, and a couple other things off that fuse. plus I dont notice an emissions common on the 87 C100.

Jacques101

So how did you mount the trinary switch to the high pressure line? I cannot find an adapter since the threads are different on the 3rd fen line. Any help would be greatly appreciated