My understanding is that the regulator is built into the tbi unit. Is it pre-set so if I change the fuel pump to a higher flow it will remain at the correct pressure for the tbi unless I go in and change it? My fuel pump is about gone and I'm going to be doing a motor upgrade. I would prefer to put a higher flow pump in now but only if it's not going to screw up the tbi stuff

 

The excesses fuel will be dumped back into the tank. Your fine to run a higher pressure pump but no need unless your planning on going mpfi.

 

We are going to put an ls based truck motor in it in the next year. wasn't sure it was a system with a return line

 

It's a PRESSURE regulator, not a VOLUME regulator.

Within it's capacity to bypass volume, it will regulate pressure. In other words, it doesn't matter how much volume the pump puts out, the pressure will remain constant. This is true until the volume of the pump flow is so great that it overloads the return system. The fuel pump supply plumbing is larger than the return plumbing on these vehicles.. The return will hit "capacity" before the supply side. At idle, it's easy enough for a very-high-volume pump to push so much fuel down the supply tubing that the return side can't get rid of it fast enough.

You'll know when this happens if your fuel pressure at high load, heavy throttle is fine, but your fuel pressure at idle can't be adjusted low enough.

Some guys regulate the voltage going to the pump--low voltage at idle, high voltage at heavy throttle. None of that should be needed if you select your pump properly.

 

There are kits to make the fuel pressure regulator adjustable.
Go with a tpi pump and you will be fine.
I did it on a crossfire, but same concept on the later model TBI units. I upped the pressure a little bit from the stock 9 psi to 12 psi and the car runs a lot better.
Check the major companies like Jegs and Summit. They all carry them.
This is on a website I randomly found doing a search.

http://marine-performance-parts.com/...843505774.aspx

 

I will need a pump with enough pressure to run a 6.0. will that be to much for the current set up to handle until the motor is changed some time next year?

 

Engine displacement means nothing. How much horsepower do you intend?

In simple terms, you need a half-a-pound of gasoline per hour, per horsepower, AT THE REQUIRED PRESSURE for your fuel system.

At 300 horsepower, you need 150 gallons of fuel per hour.

150 gallons of gasoline, at 6 pounds per gallon is 150 / 6 = 25 gallons per hour.

For practical purposes, it's easier to just move the decimal point on the horsepower number. This gives you a little "safety margin" as well.

300 horsepower = 30 gallons per hour.
500 horsepower = 50 gallons per hour

But again, you need that gallon-per-hour figure to be delivered at whatever pressure your carburetion/injection requires.