I know people have posted a lot of threads about doing a swap but i would like to get answers for my specific questions. i have a 2000 3400 and would like to swap if for a 3800 s/c.
Would it be cheaper to do a 3800 swap and add the s/c later?
How much am i looking at for doing this swap?
Would i have to do any custom fabricating?
What parts will i need?

 

It would be cheaper to just get an L67, because if you went with an L36 then supercharged it, you would likely end up spending more money. You're going to need the motor, transmission, PCM, wiring harness, inner axles from the donor car, and some exhaust work. If you budget well and find good deals, it can be done for ~$3000.

The only real "custom" work is the axles. Look up bumpin96monte's L67 swap thread.

 

It depends how much you can get them for. Looking at the averages across the places I usually look- it would be cheaper to just get a 3800SC (L67) right off the bat. You save the hassle of having to spend an extra $500-1000 on a top swap kit, and trying to get all the right parts.

Engine alone could probably be done for $1000-1500 everything included depending on how cheap you get the engine. I'd probably budget at least $2k though just to be safe.

I don't believe you'd have to custom fab anything on a 6th gen- remember the 04's and 05's came with the L67 from the factory- so any parts you need for the swap (ie any lines or anything like that) can be bought for that car (including axles if you do a 4t65HD trans swap with the engine).

Also, the 00's came with the NA 3800- which means that a 3800 SC will literally bolt in, and will plug in about 95% (with a 3800 harness)- all you'd need is the L67 swap wiring kit for the two plugs.

If you stick with your current trans and get an L67, you're gonna need a pcm tune done specifically for the setup. Its no big deal, you just tell them you want a pcm made for an L67 with a regular 4t65 so they can get the gear ratios and shift points set correctly.

Depends on if you're swapping just the engine or engine and trans, but here's what I'd think for just the engine:

engine
wiring harness from a 3800 6th gen
L67 swap wiring harness
fluids
possibly new hoses for heater, radiator, etc- but you can just buy them for a 3800 6th gen
maybe a few other misc parts I'm forgetting at the moment