Changed the rocker cover last night on the S1 from cork to the rubber one, changed rocker and charge pipe also.

Drove today to see if the rubber one let oil out and it all seems ok.

BUT...my inlet manifold seems to be hissing quite loud.
Can here it sat in the car, what does it mean? or is it supposed to do that?

 

sounds like maybe youve not fitted on a boost hose properly. check they are sitting straight and are tight. also feel around to make sure they aint split.