Just a thought, but when I pulled my EFI intake which had been installed exactly as Edelbrock specified using the Edelbrock gaskets and Edelbrock Gasgacinch on the gasket to head surface I found two places where the gasket had failed, creating one leak between two adjacent cylinders, and one runner to plenum leak. I bought a set of FelPro gaskets to put it back together, and they seemed to be much, much more substantial. I'll be using FelPro from now on.