Holley/Demon Carb stumble

mderoy340 said

My AFR recently started going full rich 10:1 after the motor was up to temp during highway cruise. Turns out the mechanical pump was percolating and the fuel bowls were low. I'm changing to an electric pump with a return line. The ethanol in the gas today sucks.

Click to expand...

Could be the winter fuel. But low in the bowls should have been a slightly leaner mix if anything. Do you have a fuel pressure gage you can mount on the cowl?

I have one but don't usually leave it on the car. its not waterproof (and draws extra attention that not always a good thing)
It sits in this location.

The steel tubing gets held under the black backet atteched tothe the washer nozzle screw.
Red strap hold s the gage to the cowl.
AN-line goes to a tee in the carb feed. AN cap when not using the gage.