I tried a search, nothing obvious.
.
Consider removing the TBI mechanical stuff, and replacing
it with MPFI, but keep the same ecm.
things to do would be...
the obvious changes, including patch wires for sensors that -
- get moved to inconvienent locations
fuel pressure change
IAC issues
peak hold v steady, issues
homemade wiring for the 8 injectors. with bigger current sink -
- drivers , if needed.
custom tune
.
OK, what didn't I consider?

 

Do you have a budget?

Depending on what it is, it may be easiest to just buy an MPFI intake. Holley makes one, I think Edelbrock does as well. Drilling out injector bungs needs to be pretty precise, I would think. The intakes are like $200.

You would probably need a new TB. Something that removes the injectors and uses a 4v design. Something like the Accel billet TB or the thereabouts.

You would need fuel rails yada yada. Yes, you would need a fuel pressure change, which would include a new fuel pump. TBi operates on low psi. Like 15 or so I think. MPFI, which would be more resembling a TPI setup, would require more like 40. Can't regulate a TBI pump to that much.

Sounds like you are planning your own custom build. Have you thought of a stand alone design such as the Holley or Edelbrock design?

 

(by ecm, I meant the stock GM ecm)
This intake looks interesting. (from Holley website)
.
http://www.holley.com/HiOctn/ProdLin.../9901-107.html
.
There are also non-vortec versions.
I think I got a carb that would fit the center hole.
Need suggestions here for the throttle position sensor.
I would use Ford svo injectors, or whatever.
.
TBI, 12 psi, ,,TPI 40 psi, aware of that.
There is a big thread somewhere on thirdgen that does
something similiar, but those folks are not using a
speed density ecm left over from tbi.
The injector drivers are NOT a problem.
Does anyone have ideas for a cold ar intake arrangement?,
in case I decide not to use an open element.
.
If this is feasilble, I would feel a lot better using the stock GM
ecm.

 

Yup, that is the intake I had in mind.

You wouldn't use a carb with that. You need a specific throttle body (you probably know that, perhaps you just misworded it). What exactly do you plan on doing for the TB?

With that, i would use something like the L69 dual snorkel design. Or something like the Ram Air box.

 

What's wrong with using the TPS that's located on your TBI?

I like home ingineered projects like this. I would:
Remove the injector pod from your TBI
Install an appropriate fuel pump and requisite lines
Drill the intake for injectors and build a little bracket.
Use Ford steel fuel rails and FPR(you can cut then braze/weld them to fit your manifold) from a junk yard.
For Cold air, use an L69 duel snorkel air cleaner.

I think the TBI TB would be sufficient once you remove the injector pod and that goofy spacer ring.

Is this TOO ghetto?

 

(Stekman, Tom, thanks for your comments)
I have two projects in mind, a 3gen F'bird, and a c4 'vette.
When I wrote carb, I really meant carb (no fuel line attached).
The 'bird (I think) has greater hood clearance, so I have
more options. For the 'vet, I just don't want to spend
500 bucks for a throttle body. I am considering using a
LS1 TB, but I don't know what to do for the 90 degree
elbow that would be needed.
...
I am sorta surprised that the TBI-MPFI is infrequently discusssed,
as I see these things as very similiar.

 

You can get a throttle body alone off of a Cadillac 4.9L MPFI engine (early 90's late 80's?). I've seen them at the junk yard. They ARE a TBI throttle body without the injector assembly from the factory and they bolt to a standard TBI pattern on the manifold (triangular bolt pattern)...

 

I'm not sure what a 5.0 TBI throttle body would flow with the injector pod removed. Or a 454 TBI throttle body for that matter but for simplicity sake, that would be my first consideration.
Either would have mounts for the TPS, linkage for 700R4 TV cable with the correct geometry, and would fit a GM air filter.
It's a clean setup once you remove the injector pods.