I have a 90 sammi WAS efi now its webbered..... there running a low psi (5-9 psi) electric fuel pump.....   My problem is it starts fine in the shop, idles good and all but when you drive it and come to a stop it dies and does so every time   ? (vacuum issues?)  It smells a lil gassy or running rich to me...  Im gettin answers from everybody and there all diffrent sum body chime in and tell me whats up.........   Glad to be a part of this forum again.....  thanx guys

That's a shame. From efi to carb Anyways I would go back to efi if all the electronics are still there.
Just my .02

the damage is done, Jluck.  Let's move on...

The first thing to check is that ALL of the vacuum ports on the intake have been thoroughly plugged.

Next, make sure that the carburetor is securely bolted to the intake and there is no air leak.  Spraying sngine starter around the bottom of the carb while the engine is running might cause the revs to jump if there is an air leak...

If you haven't already done this, get a fuel pressure regulator and install it in the fuel line at the engine.  Set it to 1.5 pounds.

finally, plumb the fuel return line to the other fuel port on the side opposite of the fuel inlet port.  It is probably plugged with a brass bolt.  This will relieve backpressure when the carb's float valve shuts.

I hope that this helps!

Ok fellas thanx but you dont even want to no what the problem was....    1 i put a fuel pressure regulator on and turned it down  fixed that   and the dieng part well that was a coil wire shorting out on the fuel pump block off plate   drove it for 30 mins no probs.....   i agree w the injection part but unfortunately it was gone when i bought it thanx again guys     

What kind of Weber is it running?  32/36 progressive?

yes red kick