Will s4 turbo fuel rails fit on an s5 turbo lim and s5 turbo middle iron?

 

The primary rail should be swappable without issue, but the secondary rails mount a little differently. IIRC, one of them is a little taller, so some modification would be needed. I can't remember which one, but you'd either end up with a fuel leak at the top of the injector or the rail smashing the injector down (w/out making some sort of spacer).

 

S4 TII secondary rail needs small spacers to fit the S5 TII LIM. no one does the reverse because the S5 rails are stamped steel garbageness.

difference between the 2 is only about 4mm in height on the legs.

 

The injectors are not a problem,as they fit like any other into the rail.
The problem is it fits too tight.But it can be rectified.
You can use a washer in between the rail and the manifold.This rings the rail UP so the injectors don't squish the bottom O ring,or possibly break the plastic diffuser.

 

so I just need to put sum washers under it, got it