I have a 350/290HP 4 bolt main crate engine w/670 Holley,It vapor lock,s after it warm,s up.has electric fuel.

Question

All your answer's were good.I have done all the above answer givin.except the insulated base plate.when i say vapor lock means Istart off w/7psi and end up with 3psi to 0psi,my glass filter shows lots of air and little fuel when it warm's up.This engine is in a 1963 chevy 2 Nova All new lines tank and vent to race specs.

Answer 1

you're saying it vapor locks.  What signs does it give that it vapor locks.  I suppose the fuel cuts off and stalls and so you say it vapor locks.  We push a lot of "vapor lock" where the trouble should be rightly be something else, the word "vapor lock" is an easy term to banter about.

Answer 2

Your vapor lock may be the fuel boiling out of the carb after shut down. There is an OEM and after market shields that goes under the carb and it has a gasket on it to shield the heat coming up from the intake manifold and boiling the fuel out of the bowls. There is one for the Holly carbs as well as the Quadrajet carbs.

Answer 3

check the fuel line from the carb,working back toward the tank,make sure the line is away from the block,manifolds etc.heat is normally what causes vapor lock,if the line gets hot from being to close to a heat source,that could be your problem.Or a bend in the line could be to tight and when it gets warm it expands,cutting off fuel delivery.

Answer 4

Every one here has given you good information. Another thing to check: Is the fuel tank being vented properly? You didn't say what the motor was in so just make sure the tank is vented according to the standards for that year vehicle. Older cars were vented to the atmosphere, newer vehicles are vented through any number of EVAP systems. Good luck.

Answer 5

Have you set the float levels in the carb?

http://www.panteraplace.com/Pantera%20Pi...

Remove the brass pan-head s***w from the side of the float tank.  The fuel should be at the base of the hole.  To adjust loosen the pan-head s***w on top of the tank.  Start the engine & turn the nut to the left until the desire fuel level is achieved. Hold the nut & tighten the s***w.  Replace the sight hole s***w.  Repeat the procedure on the rear tank if equipped.

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Answer 6

Insulate the fuel lines by the engine with anti-heat wrap tape and also get a carb insulator or heat shield/base gasket. My old 69 Charger RT 440 came from the factory with a three line fuel filter...one line in, one line out to the carb and one return line to the tank to bleed off any vapors....might be something to look into modifying if other options fail. Lowering underhood temps also helps...louvers or running a cooler engine. Make sure the carb float levels are correct also.

Answer 7

Start simple cork s***w a peice of garden hose and insulate the fuel lines. worked for me,good luck