Ls swap questions

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Isaac McCaffrey

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So I have been wondering about repowering my square and my local wrecking yard has this thing call simple part pricing which basically means that you can get a 350 for the same price as an 5.3 so I'm gonna run with that and do an ls swap but I want as much as I possibly can to be from the junkyard what do i need to do a junkyard ls swap the motor is a 5.3 and the trans is a th350 , here is the donor and what can i use off of it for my truck?
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80BrownK10

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Get the wiring harness, the computer and you may as well get the transmission or a modern transmission to get the full benefit from the swap. Make sure you get all the brackets and grab the accessories needed as I don't believe they swap over.
 

Bextreme04

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If its a 4x4, you probably don't want to go through the hassle of swapping the trans to a 4l60e. The cheapest swap is to just drop in the 5.3 with the stock computer and harness. You can rework the harness and cut out all the non-necessary stuff and then you will only have something like 4 wires to hook into the truck. You can do your own ECU tuning for about $60 by buying an OBDxPro VT tool and opensource software. You'll need to get swap motor mounts and also convert your fuel system to EFI by either swapping in an 87 TBI fuel tank and sending unit with an EP381 pump or running an external electric pump in-line with the stock fuel system.

You'll also need LS swap headers. There are also some differences between different LS motors. ICT billet has some pretty comprehensive info on the differences.
https://www.ictbillet.com/swap-guide/ls-swap-guide.html
 

Scott91370

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Accelerator pedal? Guess that depends on the engine (I didn't look at the attachment).
 

RoryH19

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Look at my k5 swap in my signature for some pointers.
 

Camar068

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if it's 4x4 just tap the 4l60e trans adapter for a camaro VSS sensor. Then get a clamp on reluctor wheel for around $100.
 

JBswth

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So I have been wondering about repowering my square and my local wrecking yard has this thing call simple part pricing which basically means that you can get a 350 for the same price as an 5.3 so I'm gonna run with that and do an ls swap but I want as much as I possibly can to be from the junkyard what do i need to do a junkyard ls swap the motor is a 5.3 and the trans is a th350 , here is the donor and what can i use off of it for my truck?
You must be registered for see images attach
A 5.3 is smaller than your 350, so it won't have the low-RPM torque as a 350. You might have to gear down, or else it might feel boggy off the line.
 

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