if i were to run an adjustable FPR in my feed line, would i still need to run the return line from the new adj regulator or will the one from tbi to tank work?
I'm not sure what you're trying to accomplish but, you don't want the fuel pump to dead head or build too much pressure. If you don't have a bypass on your new AFPR the pump will, in essence, partially dead head, especially a higher volume and pressure pump. You can plug off the return line in the TB and use it on your aftermarket regulator but, why not just convert yours with something like this? All you need is the adapter, pressure gauge, and adjustable regulator.
http://www.rvmorsemachine.com/product.htm
You just need to drill a hole through the plate for the screw and bend the MAP sensor vacuum tube down a little. The fuel lines hook up fine too.
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Here's what it looks like installed. This is when I had a 28LB spring from a 94 - 95 7.4L TB, set at 28PSI LOL.
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