Converting to EFI

[DanInMichigan]

My post above yours about Megasquirt is one of the cheapest ways to go.  Unless you already own all the donor parts it won't get much cheaper than megasquirt.  Your cheapest intake is probably a used TPI intake.

If you can get a used TPI motor you'll already have the correct sensors and distributor.  You'll also have insane torque on a 400.  Your HP will be a bit limited but for the torque I think it would be worth it.

Vortec heads will require a special lower intake intake that is big $$$.

Don't get caught up over mega horsepower.  Build something you can afford and enjoy it.

My 2 cents.

Dan

[Rich84]

^^^x2

[Captkaos]

You can usually find TBI motors complete for around $4-600, you can sometimes find people chunking the TBI for a carb for a nothing. 
If you find one from a 87-91 R/V all the stuff is there, they are pretty simple setups in my opinion.

Megasquirt is an alternative but the price doesn't come with any of the wiring.  I priced one back a while and found it was cheaper to get a used TPI and harness with a GM ECM that I can replace at any time.

Now I would just jump straight to a LS setup.