stock injector rating is 450 but at what psi?

[spaceball]

i know the industry stantard is to list flow ratings at like 43.5 psi but the base pressure on our cars in 37. so my quesion is are slock injectors rated at our base pressure, 43.5, or pressure at stock boost which would be 48 if the stock fpr is 1:1 or some other pressure that mitsu or bosch use as a standard?

 

[GVR4592]

They are rated 43.5 psi.

 

[aero_sallee]

i know the industry stantard is to list flow ratings at like 43.5 psi but the base pressure on our cars in 37. so my quesion is are slock injectors rated at our base pressure, 43.5, or pressure at stock boost which would be 48 if the stock fpr is 1:1 or some other pressure that mitsu or bosch use as a standard?

You have to realize that with a 1:1 regulator, as long as it is working properly base pressure is the only one that matters as far as flow is concerned. Your example of stock boost and the fuel pressure for example. The fuel pressure is ~48spi at that point, but there is now 11 psi pushing back from the intake against the fuel. So the differential pressure between the fuel rail, and the intake will always be the base FP setting of 37 psi (with the stock 1g regulator).

 

[dedlewamp]

Also remember that 1G Manuals have a base fuel pressure of 37, while automatics have a base fuel pressure of 43.5.