2002 LS1 into 2003 Silverado?

[yournamehere018]

I have a 2003 Silverado (short wheelbase, 4.3L V6, 5 speed, 3.42 gears) and I can pick up an LS1 with automatic tranny, wiring harness, and computer for $1500. I want to keep my 5 speed. How hard would it be to swap the LS1 in place? WOuld I need a new bellhousing? Would the computer work in my truck? Would everything hook up (emissions, fuel supply, etc)? I know exhaust will need to be made and there will be a couple clearance issues. Is there anything else I should know about?

[thunder550]

You'll need truck engine mounts and a truck wiring harness for a V8 with a PCM.

I have seen a few V6 to V8 swap threads on the various forums that I've been on, and this will be pretty much the same thing, except you'll have to get rid of the car parts (PCM and harness, and engine mounts, maybe more) and replace them with truck parts.

[txarkitekt]

It can be done, but like Thunder550 said, you will need mounts and most importantly, the wiring harness for a V8 truck. If the motor is backed by a 4L60e and you wanna do a manual tranny, you will need a new flywheel. I would recommend that you sell the auto tranny and pick up an F-body T-56. The NV3500 you have in there now is not going to be enough for the LS1. Emissions and fuel will already be in place, so no issues there. The stock PCM can easily be flashed to LS1 specs. For more info on this swap and the wiring harness, contact Nelson Performance.

[yournamehere018]

So get this crap: I came across a T56 needing a rebuild for a HUNDRED BUCKS. I was about a day too late though.

[txarkitekt]

Doh!