Hi guys, new to the forum and would like a little help. I am converting my sons 89 Formula 305 from the TBI carb to a Performer intake and Carter carb. I also have an older style vacuum HEI. I did read the article on the TPI swap and I am not sure how much of that article will relate to my swap. I think I will need at least a fuel pressure regulator with a return. The stock pump runs 15 psi, too much for the carb. Will my single electric fan still work? Will the fuel pump still work? I hooked up the battery and ran the pump with all the plugs that I am removing from the TBI unhooked and it seemed to run fine..Let me know what you guys think. I would really appreciate it. Thanks. Jay

Welcome aboard thirdgen.org.

The article is EFI to carb, the basics are the same.

Use a return-style regulator such as the Mallory 4309 to control the pressure to the carb.

As I understand it, if you leave the ECM in place and hooked up, the fuel pump and radiator fan will work. The torque converter clutch lock-up, however, will not, and you will have to do something about that.

Thanks for the info. I was hoping to hear that, as that is what I understood also. I will order the regulator today and have the thing running by the weekend. Thanks!
Jay

Does it have an automatic transmission?

Yes it is.
I just read an article and it stated I needed to wire the fule pump like this:


Cut the Dark Green/white that goes to the fuel pump relay and connect the end of the wire that goes to the relay to an unused ignition wire such as one of the wires that provide power to the injectors. Pink is one and Pink/black is the other. Either one will work. The fuel pump will then run whenever the key is on, powered thru it's original circuit.
Get the right regulator. It's called a "bypass regulator".
Don't forget the ECM controls one fan and the TCC depending on model also.
They sell switches to control these at Jegs & Summit.

Does this sound right to you?

Where is the Fule pump relay found on this car? 89 Firebird
Thanks