I have been noticing that my idle is a bit unsteady at idle (640 rpm) so I checked the vacuum and it read about 11 in-Hg but moves +/-.5, I checked it at 1400 rpm and its 14 in-Hg and fairly steady. The only port on the carb was at the base that runs a hose to the PCV valve so I tapped into that. This is a 89 OMC 460 . I am suspecting vacuum leak, but havnt found it yet.I have the timing set a 11 deg. Is this the typical vacuum at idle for BBF 460?

Thanks Jim

that is low for a stock type engine, could be a leak, carb issue, camshaft wiped or even valves not sealing, Rob