ErikwithAK01

I am in the process of rerouting a lot of things under the hood of my vette to make it more aesthetically pleasing. I want to do billet fuel rails, and would like to know if I need to add a fuel pressure regulator to the new system? Its a 2001, returnless system, and it is my understanding that after 1999, the return circuit ended at the fuel filter. The car is not going to see serious power upgrades, headers and a tune is about it. What do some of your retunless systems look like, and/or require?

LoneStarFRC

Based on your stated plans, no.

Your understanding is correct. Beginning with the 1999 model year, the FPR (and return line) were incorporated into the filter itself.

HTH

ErikwithAK01

At what point would it be necessary and/or a good idea to add one? Is it horsepower dependent, or certain mods dictate when one should be added, like fuel pumps, different injectors or whatever?

LoneStarFRC

Big HP is the main determining factor, as the stock fuel system starts to become inadequate in supplying enough fuel volume. Fuel VOLUME is the key. This would also dictate more than just a regulator as new (larger) fuel lines, bigger injectors, higher capacity (or dual) fuel pump(s) then become necessary as well. Blower and turbo cars are common candidates for a new fuel system design, less so on NA cars, but even they eventually have limits as well.

The numbers vary a little from what I've seen, but generally speaking, the 600 to 650 (~) fwhp range is where all this starts becoming necessary. I'm in the 635-640 range with a pump upgrade and larger 50 lb injectors and the OE filter/regulator works fine with my OE fuel lines.

HTH

ErikwithAK01

Concise, and informative thank you very much for the info!

BigGun

"Specifically, 97-98 on the rail, 99-early 2003 on the frame rail, 2003-2004 in the tank." Info supplied by Lucky131969.
https://www.corvetteforum.com/forums...-location.html

LoneStarFRC

Only the last year and a half was both the reg and filter inside the tank. If he had either of those two, I would have gone into that. He does not.

BigGun

I wasn't being critical of your post. It was just a fyi. I consider you an asset to this forum.

LoneStarFRC

Thank you, I appreciate the kind words.

I was just trying to keep things as short-and-sweet as I could for the OP, and not get into an in-depth response regarding the entire history of the C5 fuel system and all it's design iterations. I have to work on my brevity sometimes.

neutron82

ok now we're gonna have to take this to the honda forums jk man... 6-650 on pump gas alone is getting real close to the limit depending on the particular setup... I made a little over 700 with a 255 in tank pump, boost-a-pump, hotwire harness, 60lb injectors, and spraying lots of meth... injector duty cycle was 71% and held pressure all the way to redline... I wanted to add a couple more pounds of boost but my tuner said I really didn't have much room left so I'm building a new fuel system at the moment