Hot Rod Forum : Hotrodders Bulletin Board - View Single Post - 305 sbc good idle, Dies when in gear
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Old 11-07-2007, 03:16 PM
1drwgn 1drwgn is offline
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main reason vacuum drops is because rpm drops. the engine is not pumping as much air at a lower rpm and therefore is not pulling as much vacuum against the butterflies of the carb. just like when you are cruising on the highway, higher load at a lower rpm vacuum will be higher, something like 20 to 25 or even higher depending on the engine size and whatnot, because of rpm and lack of opening in throttle blades. hope this blurb is correct and helps.
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