Official NBS 4.3v6 to GEN 3 V8 swap Guide

You can keep the transmission, no change from auto to auto.

Go ahead and get the 411 pcm if you can. I switched PCMs when i did mine. When you get a tune they will just ask for a 4.3 core, so its no biggy to use which ever tuners PCM they provide.

Can't use the engine mounts, make sure you get the right set.

Get electric fans, more room, better cooling. ESPECIALLY for towing.

I bought 2(1 foot) steel braided fuel lines. Cut the hard lines like a few inches down from the intake, installed the hardlines and put them onto the fuel rail for the 5.3. WAY cheaper adn easier then replacing the entire fuel line assembly.

Same alternator.

Probably some odds adn ends you will run into when doing the swap. Nothing that you cant find at a junkyard or a dealer trip at all.

675 is a real good deal. I got a 5.3 for 700 with out a harness and a few other misc things

Thanks for the above info. This is really going to help.

With the used 5.3, any cheap upgrades before I install the engine? I see some talk about a cam upgrade????

Thanks again

Carnell

Yeah if the engine is already out, itd be really easy to just toss a cam in there. Figure out if you wanna boost it or stay NA first. COuple other bolt ons probably, just figure out which direction your going with the truck first I guess

Just as my Dad would say "keep it simple stupid"

I'm just looking for a little more power and a simple rebuild for longer life. Truck is paid for so it's sticking around. I'm not looking at the quarter mile or chirping the tires

from what i've seen, the comp 212/218 drives pretty much like stock + 20-30hp with a good tune & some long tubes. i wish i'd done that when my engine was out - now, i never can seem to find the time or money.

Are the comp 121/218 camshafts?

Also, if the 5.3l is the same year as my truck, will there need to be changes on the 5.3 wiring harness prior to the install?

Thanks

Carnell

p.s. What do you do at NAS Pensacola?

i have a 2003 4.3 its dbc, do i need to get a dbc harness or a dbw??? id like to keep the cable and not have to mess with the dbw, dont u have to have the gas pedal and mount and all to make it dbw??? THANKS!

Quote:

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Originally Posted by carnell

Are the comp 121/218 camshafts?

Also, if the 5.3l is the same year as my truck, will there need to be changes on the 5.3 wiring harness prior to the install?

Thanks

Carnell

p.s. What do you do at NAS Pensacola?

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it's a camshaft - 212/218 are the intake/exhaust valve lift specs, which are what cams are generally referred to by
for the harness, so long as both you & the donor use the same transmission, you shouldn't have to change anything that i know of

Quote:

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Originally Posted by 1BAD6660

i have a 2003 4.3 its dbc, do i need to get a dbc harness or a dbw??? id like to keep the cable and not have to mess with the dbw, dont u have to have the gas pedal and mount and all to make it dbw??? THANKS!

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you can do the DBC swap on a newer motor, but i don't remember what all's involved. search around & you'll come across where people've done it before

Thanks for the info. I'm still shopping for a engine. A local guy has a 02 Tahoe with 87k and he wants 800 for the engine including wiring harness and comp. I'm not sure if I want to pull the trigger.

If the Tahoe has a different transmission? Can I send the harness off the new engine to nelson tune for them to make the mods?

Carnell

same 4L60 in the tahoe - you're good to go. just check to see if the hoe has traction control or not - yes=DBW, no=DBC
and Nelson can do harness work (not that you'd need any - assuming the one they send is good). Current Performance Wiring did mine & i'm happy with it