As George said.. if the fuel is boiling, you'd know it. Car will run very sporadically if at all.

If you really suspect it... another thing you can do is pull the air filters. When the car is good and warmed up, lift the pistons in the carbs so you can see the needle and jet. If the fuel is boiling, you'll see it spurting and burbling out the jet past the needle. Car need not be running.

But, also as George said.. I think you should be looking elsewhere for your issues.

Also... the phenolic spacers can help with boiling fuel issues. They won't necessarily eliminate it. During one hot summer, I went so far as to double up both phenolic spacers, and use dual heat shields... and a variety of combinations of the order in which I put them. Aluminum foil around the jet tubes... sometimes it would seem better. Other times not. I really think the main issue with boiling fuel is the fuel available these days.. not the car.


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-Matt I ♥ my ♂