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Hey all,
I'm working on a L99/6L80 swap into my 1977 vette. Already got the frame back from Van Steel with engine mounted. Engine/trans from 2012 Camaro.
Right now I'm looking at the wiring, which I was going to take to Speartech, but they're not accepting any new mod orders right now. They said they can make me a new one for $950 + $300 for a tune... which is a little much considering I have an entire complete stock harness on the engine/trans already, shifter, and gas pedal. So new harness is out.
My goal is to keep the DOD and AFM and modify the stock harness as little as possible. Here's what I know:
1) ECM tune: need VATS removed and fan temps adjusted (at least)
2) Need to connect battery, ignition, and ground to the engine harness for it to work.
Here's what I'm not sure of:
1) dumb question: Why do I need to remove sensors, instead of just leaving them on?
2) How to wire up gas pedal.
3) How to wire up shifter to dash harness.
Any wiring experts on the forums that can help would be appreciated. Otherwise my project is at a standstill. Some helpful links below.
Thanks for the response.
I'll check with them and speartech tomorrow. Did some calling around today to PSI conversions. The guy I got told me DOD/AFM was basically not worth it, but I still think it's good to have.. want to save on expensive gas while I can..
I also checked the LS controller harness that GMPP has on chevroletperformanceparts, still no good answer for what I'm looking for. I might have to end up doing a rework with one of the shops, but if anyone has done their own wiring I'd still be happy to hear about it!
I've done my own, but it sounds like you want it hired out. Either way, you'll need to understand what sensors and functions you'll want to keep.
Try these guys: http://www.wait4meperformance.com/
For sensors, things like rear O2 are not needed without cats. Most remove egr, evap, AC functions. You will need to keep your oil pressure sender with DOD/VVT.
BTW which pan are you using that fits the vette and maintains DOD?
If you need extra connectors or something like the pedal harness, check with efi connection. http://www.eficonnection.com/eficonnection/default.aspx
Not knocking any other vendor but you get what you pay for with Speartech. John is a GM engineer who helped design the original harnesses in these cars. I have seen many threads with various vendors only to have with wiring issues they are constantly chasing. There is a reason high end shops exclusively use him. I had John work my stock LS2 harness and it was completely plug n play with zero issues.
I've done my own, but it sounds like you want it hired out. Either way, you'll need to understand what sensors and functions you'll want to keep.
Try these guys: http://www.wait4meperformance.com/
For sensors, things like rear O2 are not needed without cats. Most remove egr, evap, AC functions. You will need to keep your oil pressure sender with DOD/VVT.
BTW which pan are you using that fits the vette and maintains DOD?
If you need extra connectors or something like the pedal harness, check with efi connection. http://www.eficonnection.com/eficonnection/default.aspx
Wow Gary.. sounds like you have exactly what I'm looking for. Just to be clear - I would much rather do it myself, learn a lot, and save several hundred dollars, but I want to make sure I can do it well and do it SAFELY.
I have the cats on the headers that came with the engine, and those fit nicely into the trans crossmember so I'll probably be keeping that, meaning that I will have to keep the rear O2 sensors as well.
Excuse my ignorance here - I'm using the batwing oil pan (I'm assuming that's the "pan" being referred to here) but I entirely fail to see the connection between that and DOD.
I'll definitely have to do some more research.
Not knocking any other vendor but you get what you pay for with Speartech. John is a GM engineer who helped design the original harnesses in these cars. I have seen many threads with various vendors only to have with wiring issues they are constantly chasing. There is a reason high end shops exclusively use him. I had John work my stock LS2 harness and it was completely plug n play with zero issues.
Thanks, yeah I called Speartech today. The problem I have with them is that their website doesn't clearly list what sensors are included with their harnesses, and when I asked about it they were pretty general. I tried to get a little more out of them to see how their wiring harness would be different from anything I were to put together myself, but they basically told me I was wasting their time and they weren't going to go over every little detail about their product with me.
To be honest after speaking with them and looking around as to what's available - I'd rather do this myself to make sure I know what I'm getting.
Do some more research. I might have mis-spoke, I think there's a regulator built into the pan that's needed for VVT....or it might be DOD too. Oil flow controls the VVT cam phasing, so I've heard others keeping the stock oil pressure sender and a pan valve.
You can do the harness yourself, once you understand what all the sensors do, what you need to keep, etc. You'll need to know that either way.
BTW, you still don't need rear o2 sensors even if you keep the cats. They're simply there to monitor if the cats are working correctly.
If you haven't found it, there's a pinout/schematic thread over at the LS1tech conversion page.
Would you mind posting a link to it? all I know is what's on LT1swap. I've been looking at his finished harness vs what he started with and trying to make out the colors of the wires. ick!
I built all my own wiring for my Superlite Coupe. It was much cheaper in the long run and incorporates the BCM as well. Don't know if I'd do it again though as it took too many hours in research. The best part about it is the fact in the end you will know it intimately.
Doing the harness yourself, if you have basic skills and patience, is not unreasonable. I have done a couple for my self. It does sound like you need to do a lot of research before you start anything. You will probably find more information on swap forums like LS1tech. Research will save a lot of wasted time and money, and if you don't do the work, you will know better what you need. You could just change a few wires of the stock harness or you could re-work the whole thing to make it a custom fit. There will be lots of wires you will not need, but you could just leave them in. I found it better to re-work the whole thing. But it is not for the electrical faint of heart.
74modified pretty much sums it up. Label everything, figure out what you need and don't, take out the stuff not needed, rewrap it.
Btw, I looked at a couple threads over at LS1tech (search VVT oil pan) an see some tap the new pan and use the valve, some don't bother. Seems to work either way so you might be ok with the batwing pan as is.
Doing the harness yourself, if you have basic skills and patience, is not unreasonable. I have done a couple for my self. It does sound like you need to do a lot of research before you start anything. You will probably find more information on swap forums like LS1tech. Research will save a lot of wasted time and money, and if you don't do the work, you will know better what you need. You could just change a few wires of the stock harness or you could re-work the whole thing to make it a custom fit. There will be lots of wires you will not need, but you could just leave them in. I found it better to re-work the whole thing. But it is not for the electrical faint of heart.
74modified - well done. that looks very professional. Maybe I could send you mine...?
I will probably take your advice and only change a few wires... I've heard from multiple sources that leaving sensors on that you're not going to use doesn't affect anything.
Mostly I've been going off the diagrams posted on LT1swap, I have pretty much the exact L99/6L80 combo that he has diagrammed there. http://lt1swap.com/pictures/L99-harnes-modified.JPG
I think I have about everything pretty much figured out on the Camaro harness, gonna need to go back to the Corvette harness and figure that out next, but that's pretty well documented.
74modified pretty much sums it up. Label everything, figure out what you need and don't, take out the stuff not needed, rewrap it.
Btw, I looked at a couple threads over at LS1tech (search VVT oil pan) an see some tap the new pan and use the valve, some don't bother. Seems to work either way so you might be ok with the batwing pan as is.
Gary - thanks for following up on that.. my engine came with a broken oil pan, so real glad I don't have to change that out again!
I see there's a B/U Light Switch, LT GRN to Bulkhead #24 with power from PNK/WHT Bulkhead #5.
BUT
the 6L80 is an auto trans and doesn't have a backup light switch thing on it or on the shifter. No back up signal from the ECM either, since this is an auto trans (only backup signals on manual trans).
Any way to link the backup light LT GRN wire to the Camaro wiring harness somehow? I was thinking of gluing a switch on the shifter to trigger when the car is in reverse, but I was hoping I could do this without making any major hardware modifications.
Does the Camaro ecu put out a 12V signal or ground when it's in reverse? If so, have it trigger a relay where the old switch was.
If not, you'll have to fab a bracket and switch activated by the in car shifter or the one on the trans.
BTW, go search for my recent posts over at LS1tech. Someone is running into pressure problems with the VVT/DOD delete. You might want to transfer the valve over now.
Originally Posted by tsandrew
I've been sifting through the wiring diagrams the last few weeks.
I see there's a B/U Light Switch, LT GRN to Bulkhead #24 with power from PNK/WHT Bulkhead #5.
BUT
the 6L80 is an auto trans and doesn't have a backup light switch thing on it or on the shifter. No back up signal from the ECM either, since this is an auto trans (only backup signals on manual trans).
Any way to link the backup light LT GRN wire to the Camaro wiring harness somehow? I was thinking of gluing a switch on the shifter to trigger when the car is in reverse, but I was hoping I could do this without making any major hardware modifications.
Yea, no output from ECM (to my knowledge) about reverse, and I've looked over all the diagrams on LT1Swap and talked with Brendan who owns the website. The "reverse signal" on X1 Pin 8 or whatever is a ground signal that's supposed to be an input to ECM.
Ugh guess I'm gonna have to do something unorthodox with this one. Really not sure how this is going to work. Maybe a sticky note next to a rocker switch: "SWITCH ON WHEN IN REVERSE"
Can you send me over a link about the valve/pressure issue on LS1Tech? would appreciate it. thanks.
The "reverse signal" on X1 Pin 8 or whatever is a ground signal that's supposed to be an input to ECM.
Can't you use that to ground the reverse circuit, or at least tie it into a another switch or relay? Most likely the latter as the ECM most likely won't be able to handle the current / voltage of the reverse lights on its own.
09-01-2014, 03:35 PM
L99/6L80 wiring question...
