New Holley 750 vac sec. now 6 yrs old always read same vac on ported as on manifold/baseplate. Tech. agreed it`s not supposed to do that. something I`m not doing right? TIA
They should be the same/ similar above idle but not at idle. Unless you throttle plates are cracked open a long way (too far) at idle. Can you take a picture of the ports you are refering to?