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Thanks guys, all the information is helpful to an old novice like me.
Binderman

So would one be any better than the other?
Thanks for the input, that's the kind of info I'm looking for.

Binderman

You can switch either one to a carb, but do you want too? Let me explain.

With EFI, the compression ratio was raised back up from it's low in the 70s, early 80, because they could, and it made more power. This was done with a knock sensor that adjusted the timing with every revolution of the engine to give optimum timing under most conditions.

They also started grinding the cams with a different profile that took advantage of the fuel injection. Since the fuel mixture was normally right on with fuel injection, and the timing was adjusted constantly, the cams were ground to be much more aggressive. Also, there is no provision for a mechanical fuel pump, so you will have to go electric.

To change it over, you have to change the intake, add a carb, and change the ignition at a minimum. I've done this, and it works to a point. With the stock cam, they are very prone to detonate in high gear.You can use an ignition retard box to fix this, but it is a compromise. So really you should change the cam too.

Now, a manifold for the late engines is about $200, and a carb is$250 at best. A good ignition is $150, and a retard box adds another $100, or $200 for a cam. Add another $100 for a fuel pump, and you are at $800 to $900. A wiring harness to use the EFI is $300 to $350, and $100 for a pump. Even if you need all the sensors, thats only another $200.  $100 for a computer, and $100 more for a chip. So the price is about the same, and the EFI will make more HP, better mileage, and be more drivable.

Another thing top consider is todays fuel is formulated for EFI, and is much more prone to vapor lock that it was even three years ago. Cars that never had a problem, are now having problems with vapor lock. I've had problems with every carbureted car I own in the last couple years.

That's my take. I am converting the old 300 engine in my Buick to EFI, because I think that it's the answer. And you can do it without losing the look of a hot rod engine.

I have a choice of two Chevy 350 engines to use in a street rod project.  One is from a 1990 Impala cop car with TBI and a 7004r trans; it's seemingly in good condition, engine oil and trans fluid are both clean and clear.  The other is from a 1999 Tahoe, Vortec TPI, no trans, about 180M miles and what sounds like a rod knock.  Neither has the ECM or wiring harness.
A couple of questions come to mind:  which would be the higher performance engine?, Will the 1990 trans bolt right up to the 1999 engine?,  If I decided not to mess with hooking up the computer stuff, what needs to be done to eliminate all the computer stuff and just run as a carbureted engine?.  There's probably a lot more questions I should be asking, but just don't know enough to ask.
After reading this board for several months, there's obviously a lot of talented engine guys who know the questions to ask, but more importantly, have the answers.  I'd appreciate any help and advice you could offer.
Thanks, Binderman

I just checked out the site mentioned by Tom 36.  Exactly what I was looking for.

Fast Jimmy

GEEZE, what a great site!  Thanks for all the help guys.

Fast Jimmy

What am I doing?  Sometimes I wonder that myself Rooster!  I'm working on my 39' International 1/2 ton.  It's got a 350 Buick backed by  a Muncie 4 speed.  I just finished up installing a Dana 44 Power-loc rear end, new rear springs, Rancho adjustable shocks and an anti-sway bar.  Next up on the list of projects is all new wiring.  
I remember seeing somebody selling these heat shrinkable sleeves that had been printed with the wire designations that we use in vehicle wiring, i.e. tach, ing., coil, left tail light, ect.   And while I'll use color coded wires, it'd be nice to have these labels placed in stratigic places.  I'm sure I kept a computer file when I saw it but a while back the hard drive took a dump and I have to start over.  Yea, I know, backup, backup, backup.  
Jim

At one time I saw someone on Ebay selling heat shrink tubing identification labels for automotive wiring.  I seem to have lost that link.  Does anybody know where these  can be bought?
Thanks, Jim