Topic: DISTRIBUTOR VACUUM ADVANCE !!!
in Forum: C3 Electrical
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Canada
Joined: 3/9/2008
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Vette(s): 70 VETTE 350/300HP, AUTOMATIC, ALL STOCK EXCEPT FOR MILD CAM,LAGUNA GREY, 3:55 POSI GEARS
Car been missing a few times after I accelerate from a stop. Checked all distributor wires and coil wires seem fine. When i disconnect the distributor vacuum advance hose car runs fine, what can be causing this? Can i run it with the hose off?
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Duncanville, TX - USA
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Sounds like the timing may be off. Where is the advance getting the vacuum? From the front/bottom of the carb, or from somewhere else? Need to determine if it is ported, or straight vacuum.
Ported vac. would be from anywhere above the throttle plates, and straight vac. would be from anywhere below the throttle plates.
Ported vac. would be from anywhere above the throttle plates, and straight vac. would be from anywhere below the throttle plates.
Joel Adams
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Former Member
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Canada
Joined: 3/9/2008
Posts: 164
Vette(s): 70 VETTE 350/300HP, AUTOMATIC, ALL STOCK EXCEPT FOR MILD CAM,LAGUNA GREY, 3:55 POSI GEARS
Front bottom and i believe straight vac.
You can run without the vacuum advance hose connected, but your gas mileage will suffer. Something else to consider is that the vacuum advance device on your distributor, or the hose,may be bad(leaking) and causing a vacuum leak.
John
1973 BB 4-Speed Coupe Project Car
2009 Z06 Mostly Stock
Former Member
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Canada
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Vette(s): 70 VETTE 350/300HP, AUTOMATIC, ALL STOCK EXCEPT FOR MILD CAM,LAGUNA GREY, 3:55 POSI GEARS
Found the problem...it was a faulty pertronix ignitor. Runs fine now
in Forum: C3 Electrical
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