Im getting ready to have my intake ported for the 58mm TB, and im also going to be getting a dyno tune. I would like to get rid of my fmu and just get the bigger injectors, I am running the stock in tank pump and the add on pump supplied by ATI. Im looking @ 42"s. Do you think those would be big enough, & should i just go with 255 pump and eliminate that second pump. Im running 10LB Boost.

 

When I was running a P600-B, that was the same thing that I chose to do. I upgraded my fuel pump to the Racetronics kit that included the Walbro 255 pump and wiring harness. I also installed 42lb. injectors and a boost sensitive adjustable fuel pressure regulator. This is really the proper way to supply the fuel in my opinion, not to mention the fact that it made tuning so much easier.

 

So you are just using the racetronics pump and thats it, Plus the boost sensative APR. I found the racetronics kit, but what brand APR are you running

 

I am using the supplied vortech inline and the stocker with 42 or 50lb injectors and its good enough for my 540rwhp and 14psi.

 

When I was running my old set-up, I used the Aeromotive #13107 AFPR, which is designed to fit in the fuel rail to replace the stock unit on an LT-1.