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I've read a couple of threads where people have swapped on S5 rails on S5 T2's but none of them really answered my question, Rotary Evolution told me that if I replace the S5 rail with an S4 and do the banjo bolt mod it will most definatley fix my fuel leak. I just primed the pump and its for sure the primary rail's FPD.
So just to make sure, I can use a NA S4 Primary rails on a NA S5???
Was told I'd need an S4 UIM & LIM because the S4 primary rail wont clear the S5's UIM...
Oh, maybe.
I used S4 TII fuel rail with S5 TII LIM and FD S6 UIM.
I have to say-
if you take off the pulsation damper and do AN lines on a S4 primary fuel rail, it is hard to see how it won't clear. I mean, its just the difference in thickness between cast aluminum (S4) and pressed steel (S5). Since the UIM is also cast aluminum some grindy grind should suffice if the S4 primary rail touches it.
You can also get an aftermarket S4 style primary fuel rail for ~ $130 if you can't find a Mazda one. Still need the plastic insulator.
or you could let me help you, since this is how i make a living... and it's totally awesome seeing other people get the sales. not that i guess i'm not used to it by now.
there is some discrepancies with the non turbo UIM fitments but for the most part it was the S4 EGR from memory that wouldn't allow a S5 UIM to go onto an early block without some grinding or a blockoff plate.
Last edited by RotaryEvolution; 02-07-17 at 10:58 AM.
the pulsation dampener is also on the opposite side of the rail on the non turbo but yes, eliminating it opens a bit more space.
but i'll double check and give you a better idea tonight after i can put it all together to see any potential fitment issues, though i don't recall there even being any in this case.
Last edited by RotaryEvolution; 02-07-17 at 11:19 AM.
the pulsation dampener is also on the opposite side of the rail on the non turbo but yes, eliminating it opens a bit more space.
but i'll double check and give you a better idea tonight after i can put it all together to see any potential fitment issues, though i don't recall there even being any in this case.
the S4 primary rail will not fit under the S5 UIM with the PD on it(the PD itself is too large compared to the smaller S5 stamped one), i do have one already modified with a PD delete that fits just fine under the S5 UIM.
i verified it by mocking up a S4 rail onto an S5 block with S5 manifold.
the S4 primary rail will not fit under the S5 UIM with the PD on it(the PD itself is too large compared to the smaller S5 stamped one), i do have one already modified with a PD delete that fits just fine under the S5 UIM.
i verified it by mocking up a S4 rail onto an S5 block with S5 manifold.
Awesome man! This helps so much! I really appreciate you testing it out for me!!!
02-04-17, 01:40 PM
