Fuel line routing and lengths with Fuel rails

[nkw8181]

Hey guys I have Radium fuel rails and am trying to figure out the best way to route the fuel lines in parallel while reusing the stock Fuel pressure regulator. I want to use the Radium lines. I should say I don't currently have the motor to measure lengths. It is being rebuilt right now and I'm wanting get it running quickly when I get the motor back. As always thanks for the help.

[nkw8181]

https://www.radiumauto.com/PTFE-6AN-Hose-Assemblies-P267.aspx

https://www.radiumauto.com/Top-Feed-Fuel-Rail-Upgrade-Kit-for-Subaru-P631.aspx

If anyone wants to see what I am speaking of

[STiPWRD]

You'll need something to mount the stock FPR, do they sell a distribution block? Here's a pic of how I ran my boomba rails with the stock FPR:
47127
All of my lines coming off the distribution block to the rails are equal length. Man those radium lines are pricey.

[nkw8181]

They sell an adapter
https://www.radiumauto.com/FPR-Adapter-for-Subaru-P630.aspx

[Hindsight]

Check my build thread. I have a lot of pictures up there on how I routed the lines. I wouldn't attempt it without the engine in. I went with a dead-end setup where I have one line to the front of each rail and the back of each rail plugged. Very clean this way.

To summarize, I go from fuel pump through the firewall, then to a T fitting. One side of the T-fitting comes from the fuel pump, as mentioned, then the other side goes to a fuel pressure regulator. The bottom side of the T goes to a Y-fitting and each tip of the Y goes to one of the rails. The other side of the fuel pressure regulator goes to the return fitting on the tank.

[nkw8181]

Looks like I'm not the only one who's gone overboard on the fuel system. I have a boyd tank, Radium surge tank and Radium fuel rails. Yours looks nice BTW. What advantage /disadvantage is there to blocking of the back?

[Hindsight]

It just saves more hose and fittings and clutter. You have just one line into each rail and no lines out. Performance wise, it all works the same. Radium even shows the single line setup on their site.

Make sure you use PTFE fuel hose or your car and garage will smell like fuel, badly.

[Bob_n_Cincy]

Check my build thread. I have a lot of pictures up there on how I routed the lines. I wouldn't attempt it without the engine in. I went with a dead-end setup where I have one line to the front of each rail and the back of each rail plugged. Very clean this way.

To summarize, I go from fuel pump through the firewall, then to a T fitting. One side of the T-fitting comes from the fuel pump, as mentioned, then the other side goes to a fuel pressure regulator. The bottom side of the T goes to a Y-fitting and each tip of the Y goes to one of the rails. The other side of the fuel pressure regulator goes to the return fitting on the tank.

I'm not a fuel rail expert. I thought the main reason for fuel to continuously flow through the pipes on the engine and back to the tank was so vapor (boiling fuel) would not occur in the lines near the injectors.
Bob