Normally I can find all the information I need on my own but this time I am having a very difficult time. My question is about aftermarket fuel lines, regulators and rails.

I have seen two different types of ways to mount fuel pressure regulators. One on the firewall and one on the fuel rail. To my understanding on the fuel rail the lines are run from fuel feed line to the fuel rail then from FPR to the fuel return hard line. If the FPR is mounted on the firewall then it would be fuel feed line to FPR, FPR to fuel rail and also FPR back to fuel return line.

1.What would be the difference between these two setups?


2. This is an example of the FPR on the firewall correct?


3. In this example where is the FPR if its not on the firewall and not on the fuel rail. This one confuses me because it has a line coming into the fuel rail on one side and out the other??


4.I've also seen on tucked bays the stock FPR on the stock fuel rail but with AN lines. Is that possible?

 

Alright so both systems work the same, On the fuel rail there is a nut on both sides, one for the fuel feed and one that is sealed with a bolt or welded shut. There are some that you can put a line for a external FPR and so you bolt it to the "outlet" of the fuel rail. I hope this makes sense and I think the external FPR is alittle more accurate but that is my personal opinion others can say diffrent. Both systems work as they should but there are a few diffrences maybe someone can put there idea in aswell

 

So if aftermarket fuel rails have a spot for the fuel pressure regulator what happens if you want to run an external one? I know for mine I want to run off the fuel feed hard line into a nylon line to FPR then from other side of FPR to fuel rail and 3rd spot on FPR back to the fuel return hard line. What happens to the spot on the fuel rail for the FPR?

 

You cap it. Run your lines any way you want them. As long as there is proper fuel/pressure flowing there is no big deal. Someone is making things more complicated than they need to be.

 

Okay that makes sense. I was just wondering since I couldn't find any info. So if I run a russell nylon fuel line from the fuel feed hard line to a BDL FPR than other side of FPR to a BDL fuel rail. Then bottom of FPR have a line going to the fuel return hard line should work right?

 

All you need are the proper fittings for the rail.

 

Ok thanks. So basically the three options are

1. Fuel feed hard line->Stainless line to FPR inlet->stainless line from FPR outlet to fuel rail->third spot on FPR to fuel return hardline.

2. Fuel feed hard line->stainless steel line to fuel rail-> stainless steel line from FPR on fuel rail to fuel return hard line?

3. Fuel feed hard line->stainless line to FPR->opposite side of FPR to one end of fuel rail->opposite side of fuel rail to return hard line