Hi guys I have a 03 chevy blazer 2 door ls with a 77 sbc 350 4 bolt main everything is new pretty much I've set the timing everything with a light when ur driving it will all of a sudden start running really bad then it will clear up and run fine for a min and do it again like I said it has new everything and it runs good until it does that ibguess u can say its doin g it intermittently
Daniel r Adams
Edited by Daniel x on 05-13-22 09:00 PM. Reason for edit: No reason given.
Welcome to the site. A little more information is needed.
Are you using a mechanical fan or electric fans?
What size and type of carb is on it?
What other modifications are done?
What type of carb advance is running? Ported or full vacuum?
What is the thermostat running temperature?
Your post will be moved to the Performance Section. More board members will see your post for help.
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A 1977 model is very simple technology. What you are describing sounds more like an ignition problem to me, either brought on by a lack of electrical power/ground or the actual engine timing.
To me runs fine then runs poor then back says fuel. Runs than stops then runs says look at wiring. I have no idea on the timing as described but I don't suspect it.
Dirty fuel or fuel pump are possible and are kind of leading my thinking.
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