Hi Fast355 Your Marine 395 cam has somewhat similar duration to my cam. I had to remove my intake manifold to swap out the HEI over to the L31 distributor to provide the CPS. the intake ports were heavily stained with fuel/carbon deposits al the way up to the TPI runners. I thought this to be excessive. This past summer, the engine had done a lot of idle tweaking with the OBDI set up. I understand big cammed engines have no business sitting at idle for extended periods of time. I do have a few questions regarding your set-up. - What vehicle is this engine in ? -or going in? - What RPM did you get the idle to settle at? - What have you done to the idle tables to compensate for the false lean condition the O2 sensors would read at idle ? - Are you running open or closed loop when idling? - Does the sequential injection and COP offer any help with a high overlapped cam at idle ? If there are any others who have comments to offer - please do. Thanks in advance. Cheers. Mikey G