Hey guys im installing my rebuild S5 n/a and i read that the s5 primary rail is know to leak and cause fires. I dont knowbhow many miles my primary rail has and I rather upgrade it or mod it?
does anyone well a upgraded primary rail that I could use the stock n/a fuel injectors?
What do you guys recommend do?

 

Swap a series 4 fuel rail on there. It will fit your injectors perfectly although I can not speak to the clearance between the fuel rail and VDI valve on s5 intakes. The Fuel Pulsation Damper (part that leaks) is removable on s4 rails. You just need this bolt to delete it:

Earls banjo bolt part no: SS997591ERL

note: getting rid of the Fuel Pulsation Damper (FPD) will put more strain on the fuel pump. Not that this matters much. I’ve never seen a pump fail from lack of FPD, but have seen plenty FPDs leak and burn down cars.

 

I thought it was the other way around. That the '86 -'88 FPD leaked and putting the '89-'92 rail on resolved the issue.