LS1 3rd gens
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LS1 3rd gens Just wondering how many of us are on here and who has good info on doing the wiring yourself and LT headers. The only LT header option I see is modifying hooker SC LTs. Wiring just scares me... not sure if I want to tackle it or not. Some people say its not that hard, others say its hard. What gives? I'm close to putting mine all together in the car, just need headers, clutch, and wiring.... I'm getting tired of looking at this in my garage... 
up on stands
LS1 and T56 ready to go in
no motor
Thanks for any help!
-Jeremy
up on stands
LS1 and T56 ready to go in
no motor
Thanks for any help!
-Jeremy
Wiring is easy but time consuming.
MrDude_1 collected a good bit of info on wiring that may or may not be useable for your car. I think his is a '91.
There's so much variation in connector pinouts from year to year on thirdgens that I don't even bother posting mine...my '82 C100 and C207 pinouts undewent at least 8 changes just to get an '88 TPI harness to connect and function back when I did that swap. If someone's swapping an '01 LS1 into an '82 Camaro they're in luck, otherwise it's worthless.
MrDude_1 collected a good bit of info on wiring that may or may not be useable for your car. I think his is a '91.
There's so much variation in connector pinouts from year to year on thirdgens that I don't even bother posting mine...my '82 C100 and C207 pinouts undewent at least 8 changes just to get an '88 TPI harness to connect and function back when I did that swap. If someone's swapping an '01 LS1 into an '82 Camaro they're in luck, otherwise it's worthless.
I saw your post in my thread about some wiring questions, i will send you a pm about the wiring. As far as headers go i am not sure of any on the market yet, but then again i havent been looking for any. Hopefully someone will come out with a decent set in the near future, because if i get too caught up in my thirdgen i may have to get a custom set made.
That's why I just had speartech modigy the LS1 harness for my car. Sure, it's some serious cash outlay - but it saves sooooo much time and hassle, that to me it was well worth it. From what I understand, every year 3rd gen had somewhat different wiring, and even the camaros and firebirds differed quite a bit in some of the same production years. If you're a wiring guru, I say have at it and give it a go. If you're not (like me), then what I paid Speartech is money well spent and lets me sleep well at night knowing it's all correct.
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Originally Posted by 89FormulaLS2
That's why I just had speartech modigy the LS1 harness for my car. Sure, it's some serious cash outlay - but it saves sooooo much time and hassle, that to me it was well worth it. From what I understand, every year 3rd gen had somewhat different wiring, and even the camaros and firebirds differed quite a bit in some of the same production years. If you're a wiring guru, I say have at it and give it a go. If you're not (like me), then what I paid Speartech is money well spent and lets me sleep well at night knowing it's all correct.
How much? Did you ship your 3rd gen and 4th gen harness to them or what?
You might want to get familiar w/ the search button, lots of relevant info you'll want to digest. It's only been a whole day or so since this exact subject was discussed with another '91 owner...
https://ls1tech.com/forums/conversions-swaps/297938-plug-play-harness.html
https://ls1tech.com/forums/conversions-swaps/297938-plug-play-harness.html
Trending Topics
Originally Posted by crainholio
You might want to get familiar w/ the search button, lots of relevant info you'll want to digest. It's only been a whole day or so since this exact subject was discussed with another '91 owner...
https://ls1tech.com/forums/showthread.php?t=297938
https://ls1tech.com/forums/showthread.php?t=297938
on a related note....
have you noticed how much the search feature SUCKS on this website?
i donno what the deal is... perhaps its rating threads, or it doesnt update the search database often, or whatever.... in anycase, i can make a post, then the next day, search on words or even phrases i KNOW i posted, and search under my name, and it doesnt come up.
the search feature is either buggy, or it uses some thread rating system or somthing... because its really hit and miss.
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From: St.Louis, Missouri
Originally Posted by crainholio
You might want to get familiar w/ the search button, lots of relevant info you'll want to digest. It's only been a whole day or so since this exact subject was discussed with another '91 owner...
https://ls1tech.com/forums/showthread.php?t=297938
https://ls1tech.com/forums/showthread.php?t=297938
*Thanks for the link to that other post though!
Originally Posted by GTA91
How much? Did you ship your 3rd gen and 4th gen harness to them or what?
John charged me $750 for reworking the harness, and there are about 8 wires or so that will need to be tied in to the dash in order for the stock gauges to work. (Speedo and Tach need signal converter adapters, as well).
I went the $750 rework option because I needed to keep all the emissions equipment intact. Otherwise I could have gone the $450 option and had them make a custom harness from scratch, and just sold the stock LS1 harness.
I also paid him $50 to reflash my PCM from an A4 to an M6.
Originally Posted by GTA91
Yeah, I agree with Mr. Dude.... I always try searches... never much luck though.
*Thanks for the link to that other post though!
*Thanks for the link to that other post though!
You want to use the Advanced Search feature, not the little popup box. This lets you pick specific forums and narrow the date range.
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From: St.Louis, Missouri
Originally Posted by kickassT/A
don't flp headers fit without a problem? one of my friends has a turd gen with an ls1 in it, and that whats on his car.
Any chance you could get me his contact info? I'd like to talk with him about his headers.
Thanks!
i made a set of headers for my 67 pickup i have a 6.0L in. I started out with mustang GT shortie headers, and cut the clanges off, reamed the tubes round again and then flattened them to match the oval of the 6.0l/ls1 ports then welded to my flanges..everything done i had $130 and about 5 hours in my headers.
the mustang shorties sweep back without droping much from the exhaust ports, not sure but they might fit in a 3rd gen.
as for the harness, i just got done putting a LT1 in a 88 Firebird (originally 305 thorttole bodie) was able to get all guages working and speedo with stock lt1 harness...only used a few wires from the factory harness.
I found the power wires in the harness, removing the fueses, and using a ohm meter to find which wires went to which fueses, the LT1 computer coil, injectors uses the fueses on the fues panel as they are labled...nice install.
gm is nice that colors are for the most part very common among gm vehicles.
pinks are key hot, oranges are hot at all times, green is usually temp signal, etc etc...
good luck, im in souther missouri, your in St louis..pm me with any qustions ive done a few swaps
the mustang shorties sweep back without droping much from the exhaust ports, not sure but they might fit in a 3rd gen.
as for the harness, i just got done putting a LT1 in a 88 Firebird (originally 305 thorttole bodie) was able to get all guages working and speedo with stock lt1 harness...only used a few wires from the factory harness.
I found the power wires in the harness, removing the fueses, and using a ohm meter to find which wires went to which fueses, the LT1 computer coil, injectors uses the fueses on the fues panel as they are labled...nice install.
gm is nice that colors are for the most part very common among gm vehicles.
pinks are key hot, oranges are hot at all times, green is usually temp signal, etc etc...
good luck, im in souther missouri, your in St louis..pm me with any qustions ive done a few swaps
Originally Posted by GTA91
Thanks for the info man!
*As for those 4th gen FLP headers up above.... they will NOT work.
*As for those 4th gen FLP headers up above.... they will NOT work.
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Originally Posted by TJ
ouch. sounds like you have tried them and wound up with an empty wallet.
*Believe me, I test fitted them on my engine stand with a stock k-member bolted to the engine.... it just won't work. This is why I just ordered my Stainless Works LS1 full length headers from www.hawksthirdgenparts.com today