Basics for a LS swap into a 1990 Chevy C1500?
06-08-2016, 10:43 AM
#21
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91 k1500 ls swap have a 91 k1500 that I am putting a 01 5.3 in I have already bought the motor mount plates and everything to make it work. but I was wondering if my stock gauges in the truck will work. ive made my own stand alone harness took the harness of the 01 engine and the ecm also. now I just need to figure how to get my gauges to work. anyone else done this?
06-08-2016, 10:45 AM
#22
have a 91 k1500 that I am putting a 01 5.3 in I have already bought the motor mount plates and everything to make it work. but I was wondering if my stock gauges in the truck will work. ive made my own stand alone harness took the harness of the 01 engine and the ecm also. now I just need to figure how to get my gauges to work. anyone else done this?
You will have to get adapters for the sending units to fit the LS engine if they don't already fit. My guess is they won't since the LS series is all metric threads and the sbc was all standard threads. Look for adapters and you should be fine.
06-08-2016, 10:48 AM
#23
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You wont be splicing anything. What he is saying is mount your original sending units for oil and temp in the new engine. Find the plugs for them in the original engine harness and plug them in. That will allow your original dash gauges to work properly.
You will use the 6.0 harness but you have to convert it to stand alone. Or buy a stand alone harness already converted.
Don't forget to have the Ecu programmed to turn off the VATS so you can start it and run it. If you have done a lot of engine mods, you will need to find someone to tune it for you to get the most out of your combo.
You will use the 6.0 harness but you have to convert it to stand alone. Or buy a stand alone harness already converted.
Don't forget to have the Ecu programmed to turn off the VATS so you can start it and run it. If you have done a lot of engine mods, you will need to find someone to tune it for you to get the most out of your combo.
so just use part of my old wiring harness and the original sending units off my original engine and mount them to the 5.3 and plug the old harness into them?
06-08-2016, 10:51 AM
#24
Yes. But do not replace any current sending units because the efi uses those as part of the tune. For oil pressure you can drill and tap the cap that is bolted to the side of the oil pan just above the filter. Be careful of your sending unit's direction and size when you mount it so you don't hit anything else close that would prevent it from fitting.
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Homer_Simpson (08-18-2022)
06-08-2016, 10:55 AM
#25
Yes. But do not replace any current sending units because the efi uses those as part of the tune. For oil pressure you can drill and tap the cap that is bolted to the side of the oil pan just above the filter. Be careful of your sending unit's direction and size when you mount it so you don't hit anything else close that would prevent it from fitting.
06-08-2016, 10:59 AM
#26
If it's the same wire as the S10, look on the drivers side by the brake booster. Follow the wires going under the cab from there and find a grey wire. If I am remembering right, that is the fuel pump lead. You can NOT power it directly from the Ecu of the LS harness. That lead is to ground a relay for the fuel pump.
06-20-2016, 12:48 PM
#28
There are several swap header sets available thru jegs or summit and on eBay. Just do some checking and research. Call them up and ask what they recommend for a swap set. Tell them what all had been done and what you want to do so you get the size that will benefit the most.
11-15-2016, 11:35 AM
#32
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mounting plates I did the 6.0 swap in my 94 silverado all my gauges work fine I used a 4l80e .stock gas tank with 98 silverado fuel pump ac delco direct fit.shoenfield swap headers direct fit.trans adapt motor plates from jegs $65.00 and a custom wiring harness from current performance.wiring harness is pricey but it plugged into my fire wall just like oe my check engine light work as if I had the oe motor.
01-19-2017, 09:55 AM
#34
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I don't know if this will help but it is what I am doing. I am putting a 454LSX/6L90E into a 1990 454SS truck.
For the gauges to avoid running redundant sending units I am using the Lingenfelter CAN2 conversion box to send the signals to the dash. It will run the speedo, engine temp, autometer tach, and fuel guage. Voltage will just come from a good source in the original harness. I wanted a stockish look. Love the Dakota Digital gauges too.
For engine mounting I went with BRP adapters and BRP/Hedman headers.
Computer and harness requires calling Speartech for their harness. They will program the transmission computer at the same time they build the harness so that the ECM and trans talk together the way they are supposed to. They are great to work with.
Lots still left to do but that's my plan so far. Builds here and on LS1truck are good to check out too. There are some good videos on You Tube also.
Good luck, Tom
For the gauges to avoid running redundant sending units I am using the Lingenfelter CAN2 conversion box to send the signals to the dash. It will run the speedo, engine temp, autometer tach, and fuel guage. Voltage will just come from a good source in the original harness. I wanted a stockish look. Love the Dakota Digital gauges too.
For engine mounting I went with BRP adapters and BRP/Hedman headers.
Computer and harness requires calling Speartech for their harness. They will program the transmission computer at the same time they build the harness so that the ECM and trans talk together the way they are supposed to. They are great to work with.
Lots still left to do but that's my plan so far. Builds here and on LS1truck are good to check out too. There are some good videos on You Tube also.
Good luck, Tom
08-22-2017, 08:41 PM
#35
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Im going a engine swap also on a 1993 GMC c1500 automatic with a tbi. I have a 5.3 ls now.
My question is do i have to remove the old pcm and wire harness?
I only have the engine. Should i get the 5.3 harness,pcm aand fuse box from a donor vehicle?
My question is do i have to remove the old pcm and wire harness?
I only have the engine. Should i get the 5.3 harness,pcm aand fuse box from a donor vehicle?
08-22-2017, 10:20 PM
#36
TECH Senior Member
Yes, all that, and from a vehicle as close in spec as the one that your engine came in.
08-22-2017, 10:42 PM
#38
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4l60-e
12-22-2017, 12:41 AM
#40
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I have a 2002 donor truck with a 6.0! Would like to swap into my 89 c1500 and keep original Manuel trans, what needs to be done for wiring? I will use complete ecm and underhood fuse box, but what about tcm and wiring, would I have to have ecm flashed for manuel trans, this is my first ls swap any info would be greatly appriciated