I am not super knowledgeable about the ITBs, so I can't keep in mind within the setups I've observed if Just about every throttle provides a vacuum reference line or a little something very similar? If those aren't connected you might have some good vacuum leaks. The left flywheel pictured https://blacktop4ageforsale83714.bloginwi.com/66314687/rumored-buzz-on-4age-blacktop-engine-for-sale