When I install my 6-8psi pump, can I leave my old pump in the tank? Anyone know from experience?

Only from reading reports on this Board.

Some have no problems, others ended up dropping the tank to cure starvation.

My recommendation would be either to power it or remove it.

So some people have had problems with fuel starvation leaving it in? Would this only be a concern with a "thirsty" motor? I will just be using the 305tpi long block, converted to a carb. So I might be alright? It probably IS a good idea to drop the tank, but I really don't want to if I don't have to. I've heard its a B**ch.

Is the stock intank pump good? If so, Just you a mallory 3-port return style AFPR. Thats what I am running.

I have the stock TPI pump in the tank. The pressure is cut down to about 6 psi. Everything seems to run fine.

Yeah the stock in-tank pump works fine. I read on http://5finger.8m.com/tpi2carb/tpi2carb.html that the guy had a lot of problems with it, so I was skeptical about going that route. Maybe he was just really bad with fuel lines?

I keep hearing about the mallory regulator, but what's wrong w/usnign a 2port, & use the 2nd port for the return?

I dont think that the 2 port is made for a return. It is to just have 2 supply lines.

I have not had any problems with the mallory so far. There are quite a few people running them. The problem with it spiking may be because of the TPI fuel pump. I think it puts out close to 55psi. The TBI intank pump puts out around 15psi. So the TPI tank is getting cut down quite a bit. The TBI wouldnt be cut down as much.

2 port regulators dont cut it. i used 3 of those before i went to my Mallory 3 port and i must say it works amazing. i spent 90 dollars on it, and 10 more on a little guage i plumbed in after the regulator. With my old motor in i had the fuel pressure down to 8 (thats what was reccomended) and no problems. The V-slick pump puts out about 45 PSI.

I had the lethargic 2.8 MPFI in before. I dont know if there is a difference between a TPI pump and a 2.8 MPFI pump