Are the S4 NA injectors all 460cc? Is there any difference between the primaries and secondaries? Is there any point to putting larger secondaries in? Is it necessary to have the "fuel diffusers" in the upper intake manifold? My one UIM has them and the other doesn't for some reason (if you've had your UIM off, you know what I'm talking about... the diffusers are visible right where the UIM meets the LIM.



Chris

 

There is no point of having bigger injectors unless you have a heavily ported engine for high rpm.



You need the diffusers so the fuel can me atomized better with the air.



The injectors also sit on it so they provided the supports and the right height to press agaist the fuel rail.



C

 

Thanks turborotor... I wonder why the one man doesn't have them?



So is there any diff between the primaries and secondaries? All 460's?

 

i had mine out and they r the same theirs no difference in them