Flathead efi issue

[Bored&Stroked]

The question of fuel filter placement depends on the application, type of fuel filter and the type of pump. Most fuel fuel pumps are designed to be as close to the tank as possible -- as they "push" far better than they "pull" fuel.

With that said, in many high performance EFI fuel systems, we'll have a larger micron fuel filter before the pump (to protect it from damage due to debris in the fuel) and a much smaller micron fuel filter AFTER the pump - to protect the very small orifices of the fuel injectors from clogging (due to smaller debris).

Almost all the fuel filters I've used in the above situations use a fine mesh screen in them (different micron mesh for before/after) - as they need to flow a lot (high horsepower) and can be cleaned and reused. Also, as most EFI systems have return lines, the overall fuel system flows a LOT more fuel through it, than the actual engine is using at any given time.

Another consideration can be fuel temperature - which can increase rapidly due to the amount of cycling through the system (especially low speed). When a car is idling or in traffic a ton of fuel is being pushed through the system and recycled right back to the tank - and the temperature keeps going up. To help with this, we will use fuel coolers and/or fuel pumps with control modules to slow down the fuel volume in these conditions.

As I'm not familiar with your actual system components, the above may be off base - just wanted to throw it out there just in case some of it applies.

Best of luck!
D