I'm looking at a 94 model Silverado with 4.3 and auto tranny. The LS engine I can get from a friend is from a 2005 avalanche. Can someone give me a rundown of what I will need to complete this swap. I do not need to worry about passing any emissions tests in my state. The engine I am getting will have all the accessories on the front including the AC compressor. Can I make these work with the swap or would I need to re use the accessories from the 4.3, if so what is involved in using them on the 5.3 LS. Will the stock tranny that is in the truck behind the 4.3 hold up or should I change it as well??

I am very mechanically inclined, just looking for a parts list I guess you would say so that this swap go as smooth as possible.



I would love to do this swap while keeping costs to a minimum, I have access to alot of Junkyard parts if that helps any with the swap

 

are you going carb or fi. you can use the stock manifolds and accessories from the 5.3. the 94 stock truck radiator will work also just use the avalanche hoses. stock tranny will work also. you will need flywheel spacer. if going carbed, you need intake and msd 6010. fi adapter for fuel line and maybe change fuel pump and ecm and wiring from donor vehicle. the tranny should stand up behind that engine.

i think the carbed swap will be the cheapest. carb intake, msd 6010, and bypass fuel regulator will be around $650 from street side auto with free shiping and around $50 in gift cards.

i don't know bout fi but i know you will need to get ecm reflashed with some options deleted, either a stand alone harness, rewire your own or have some one rewire it.

 

I will be wanting to go fuel injected

 

www.LS1Truck.com They've done that swap over there a few times, lol.