What do I need to swap??? 2002 6.0 liter vortec Chevy motor in a 1970 Lemans.;..
 

I might get a 6.0 liter vortec V8 from a 2002 chevy 4 wheel drive truck complete. It puts out about 300Hp stock. What will I need to mount it in my 1970 pontiac Lemans?

The LS1 to Chevy SBC mount adapters that bolt to the block

A fuel injection gas tank and electric pump

Some rewiring

A transmission from a similar year car so the computer can control it and also to match the bellhousing bolt pattern. (you could use an adapter but you'd still need to figure out how to cut that part out of the computer if you used an older transmission)

Proper fuel lines

Steering pump adapters or custom lines

VATS eliminator

That's all I can remember right now :)

lots more info over on ls1tech.com in the conversions and hybrids section

I've been through this swap already. Not in a Pontiac, but in my 87 Iroc before. Go to yearone.com, they sell the LS1 mount kit there, includes new crossmember as well if you run the 4L60E or a T56 with it. Now you can use any chevy transmission you want without adapters. The bellhousing on the LS1 is different than your typical chevy but by 1 bolt, some drag cars in Orlando are running TH350's with that 1 bolt not there and have had no issues with over 1500+RWHP. You can use the stock computer or get a painless perfect engine system which inclue harness, computer, and even a nice camshaft. I would stick with the factory computer and send your factory harness off to www.speartech.com He did my harness in my Iroc and will convert your factory one for like $450 bucks. Tell him ahead of time if you running the 4L60E or an older tranny and he can delet the wiring for you. You don't NEED to delete the wiring for the tranny but it would clean it up a bit. The engine will run fine even on a stock tune with a TH400 etc, but might as well delete the transmission functions in the computer if you get it tuned. If you don't want to swap gastanks (a popular one is getting a 94-96 Impala/Caprice tank and modifying the straps to fit our cars, comes with an intank pump), you can run a tube from your tank to a high pressure inline pump (the BBK universal inline or the Aeromotive A1000 would be perfect) and run braided or some sort of high pressure line to the engine. I am using a sump kit and running AN braided line from the factory sumped tank to an A1000 and then to my aeromotive AFPR. I would also suggest running an adjustable fuel pressure regulator as well with the built in return line (which you will also need to run back to the gas tank, no biggie, they make some cheap easy kits for that). I used my factory power steering lines but I'm sure they are different than your Lemans. LS1Tech has alot of info on Chevelle swaps which is the same thing for our cars. If you have any questions shoot me a PM. I put a 2000 Corvette LS1 with a camaro T56 into my 87' Iroc, it was originally a 305 TPI/700R4 auto car, so I did alot of modifying to it, even made my own long tube headers for it. But Hooker sells ones for the a-body now so you could pick those up as well. Hope this helped.

just turn it into a carb motor, easy swap.

You still need the computer to fire the ignition system even if you put a carb on it.

MSD stand alone ignition for LSX engines comes with the Performer LSX carb intake set :)

No..edelbrock sells the intake with MSD box, comes with a few different ignition curves. its a stand alone ignition.

Still need the computer for the o2 sensors, knock sensors, timing, etc.

nope, all the EFI functions are gone, timing is a function of the MSD box, you have a few different curves to choose from. you only need a few of the OEM sensors, for the firing signal
http://www.msdignition.com/2005/2005_3.htm