Jump to content


fuel rail installation question

Jeff Berk

Recommended Posts

I'm installing a fuel rail with a gas tank return on an SU fuel system. A PO removed the original fuel rail and set the fuel system up as a dead head which is causing some vapor lock issues when the car sits between auto cross runs. 

The issue I'm having now is how to attach the aluminum fuel rail extrusion. There are four 10mm bolt holes on the cylinder head (circled in red), two wire loom screws, and valve cover bolts as possible mounting options. The cylinder head bolt holes would be a good option except that they are so close to the intake manifold flanges that I'm not sure they will be something I could use for mounting. Also, is there any off the shelf fixture for mounting the fuel rail extrusion or at least a design I can copy?

Fuel rail question.jpg

  • Haha 1
Link to comment
Share on other sites

Never seen a published solution for using an extrusion on an SU manifold, but I bet it’s been done. 

Heat wise, I’d be tempted not to mount the rail to the head. There are plenty of un-used mounting points on the balance tube that I would likely press into service.

The stock fuel rail return line has a tiny orifice hole in the tip where the 3/16 hose gets clamped on, this is the stock pressure regulation. I’m hoping you plan on running some sort of regulator on your system on the return side of your rail. 


Link to comment
Share on other sites

Plumbing and electrical fixtures offer a wide assortment of possibilities especially if the final route to the carbs is rubber hose.  Many come with rubber or plastic grommets inside.

Don't forget to insulate the rail.  Nissan made up a whole fancy insulation package for the rails to combat heat soak and percolation.  That aluminum is going to soak up the heat.

Link to comment
Share on other sites

The fuel will enter the fuel rail at the front and has two ports for the pair of SUs. Excess fuel flows out the rear of the fuel rail to a low pressure regulator mounted on the firewall. Fuel then flows to the return line which hopefully has no leaks in it.

As for insolation, I'll likely wrap it with something.

Link to comment
Share on other sites

  • 5 months later...

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Create New...

Important Information

By using this site, you agree to our Privacy Policy and Guidelines. We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.