You'd could also try what Jeff said and run rubber hoses straight to the carbs instead of the oe fuel rail. Cost maybe $10 for the low pressure fuel hose. 

I'd definitely get that problem solved before painting your car. 

Priority planning

 

 

Take a look at this video and give me your thoughts:

https://www.youtube.com/watch?v=F6wGuYBiRLw

Car is right now at the paintshop! Already bought a Holley 1 to 4 psi regulator which i shall have installed once the car is painted. Is it still necessary to purchase the gas tank braided hoses?? Mine are the original once and look worn!

Replacing rubber, whether for fuel, brakes, clutch or water, is a must. The gas tank hoses attached to the breather tank can be made from pieces of standard hose linked together. For the fuel hoses, I like to use high pressure fuel injection ones as they handle aging a bit more than the average rubber hose.

Your tank will leak once those old hoses give way likely right after you fill up and make a hard left turn up a hill.

4 hours ago, jalexquijano said:

I have an Airtex 8012S electric fuel pump rated 5 to 9 psi and still have vapor lock issues. Whenever my car sits on traffic for long time plugs get black and rear carb gets really hot.  My father who is an industrial engineer and has quite some knowledge on mechanical engineering concurs with the opinión that its fuel percolation. Too much heat from the manifold to the float bowls. The stock heat shield on the 240z must be modified. Maybe using stainless Steel. Just too much heat in Panama: 33 degrees Celsius + Engine heat. Imagine???

 

 

Dude.. you have about 57 threads on this subject and now you're hijacking someone else's thread? Very bad form 

Not hijacking anything! Just trying to get a solution to the vapor lock issue at idle!!

On March 5, 2016 at 9:10 AM, Mark Maras said:

  Chickenman or anyone else, were the 70 & 71s plagued with vapor lock and or percolation as much as the later SUs? Having driven an early 71 for years and never had a problem with it, It seems to me, every time they "updated" the SUs the problem became worse. Any truth in this theory?

I've driven my '71 for 45 years without any vapor lock problems.  Summer temps run about 115º here in the desert.

Dennis