I have no clue

[Mopar85]

I am having a mystery problem in my car. runs fine when cold but as soon as it warms up the fuel pressure starts to bounce from 15 to 10 psi. running a holley blue with the regulator that comes with it set at 8 psi. after it warms up while driving it starts to pop in the exhaust and sometimes backfires with 93 octane.
i am thinking about switching to a return style fuel system.
any clues?

 

[Mrmopartech]

Sounds like a over heating gas line to me.Try to insulate the line from any heat source,headers and mufflers,and engine heat to be sure,should clear up the problem,mrmopartech

 

[Mopar85]

I put some dei heat shield on the line where it gets close to the headers.