73-87chevytrucks.com
73-87 Chevy _ GMC Trucks => Engine/Drivetrain => Topic started by: atxcobra on July 20, 2007, 06:46:41 pm
-
ok ive got an 81 with a 400 small block and when i put the pedal to the floor and then let off it backfires really nasty it sounds like a gunshot from my engine lol. what could this be due to im really new to carb engines and to this truck i just bought it, my thoughts are too much timeing or bad carb. please help me out and if you need more info on the engine ill supply as much as i know.also does it affect the performance having this problem? as far as i can tell this truck hauls butt and doesnt hesitate so other than the embarrasing backfire i dont see a problem.
-
check the plugs and wires, check the cap and rotor. Then set your timing.... go from there.
-
Backfires are explosions in your exhaust...your exhaust can only take so much. It is bad for it.
Do what Vile suggests.
Do you have any exhaust leaks? Air is getting into your exhaust system and when it meets raw fuel (do to a miss or bad timing lilke Vile says), since the heat is already there ...BOOM
w
-
thanks for the help guys ill look into all of this. the wires look good to me they look pretty new and there taylor racing wires ill pull a plug out today and ill check for leaks. what do i check with the cap and rotor
-
See if there is any corrosion on the metal terminals or cracks (lines) in the cap.
-
I am wondering if your carb is running really rich allowing extra gas in the exhaust system...just throwing things out there.
-
I am wondering if your carb is running really rich allowing extra gas in the exhaust system...just throwing things out there.
how can i check for that cus when i get on the truck it really really smells like gas