besides needing premium fuel only what are some of the advantages of having pfi over tbi or vice versa. Im not sure if I want to seel my 88 eldorado (TBI) to get a 93 eldorado (PFI). also what happens if you put regular fuel in a port fuel caddy. any information would be greatly appreciated. :feedback reciated.

i think if u add regular fuel the computer will figure it out with the knock sensor and it will just go sluggishly so as to not blow. i dont think tbi vs pfi requires any kind of fuel inherently but either kind of system can be designed for either kind of gas. what really determines what fuel u need is when you gas it then the heads and the cam do the wild thing and hopfully u have the right gas. on a caddy i would presume it would be happy with premium, mine is, but its 35 years old and huge so i dunno about yours