I'm just curious if its possible to run JUN cams 272 duration 11.5 lift without Springs being that S4 cams have 11.8 lift and don't use springs springs are mainly for Lift correct? What about using Springs without Titanium retainers...the retainers alone are like 270 bucks ...anyone have numbers on 272 Duration 11.5 lift cams? Thanks for any insight on this