Why is the base fuel pressure higher on the later model cars?
 

Hi,

My early NB has a 3 bar referenced fuel pressure regulator, and my MSM/SE had a 4 bar static regulator.

Do you know why Mazda made this change, is it for better atomization at idle?

Do you think it is worth the effort of fitting an aftermarket regulator and setting it to 4 bar without any manifold reference?

Cheers

Fuel is heated much less on returnless systems.