F-1 Cylinder Head Design

[gunt]

If they use 2 sets of injectors, 1 shower and 1 conventional , they could simply use 2 different pressures on each rail , it could account for it

[Brian P]

The engines that I am aware of that use both close (downstream of throttle) and far (at inlet to intake runner) injectors feed them from the same fuel pressure. Same pump, same regulator. The differences in pressure across the two injectors because of the shut throttle is accounted for in the mapping. (actually, in part load conditions in which there is significant intake vacuum, only the close in injectors are in use anyhow).

Even with the engines that use both direct and port injection, they are using the same fuel pressure. (The port injectors are running at direct injection pressure.)

[midnightbluS10]

The engines that I am aware of that use both close (downstream of throttle) and far (at inlet to intake runner) injectors feed them from the same fuel pressure. Same pump, same regulator. The differences in pressure across the two injectors because of the shut throttle is accounted for in the mapping. (actually, in part load conditions in which there is significant intake vacuum, only the close in injectors are in use anyhow).

Even with the engines that use both direct and port injection, they are using the same fuel pressure. (The port injectors are running at direct injection pressure.)

Speaking of that, and I realize it's not F1, the new LT5 has dual injectors like that. 1 set of direct injectors in the combustion chambers and another set in the ports to provide extra fuel when DI can't keep up. They actually do run on 2 different pressures.

The PFI system is supplied by the fuel tank’s electric pumps at a pressure of 58 psi and for fuel injected directly into the cylinders delivery pressure in increased to 2,900 psi by a high-pressure pump. This mechanical pump is driven by an extra lobe on the camshaft in the same location as the Gen I cam’s distributor drive pinion and was first used on the 2014 naturally aspirated LT1. This pump was bored and stroked to increase its capacity for the supercharged LT4, and now the LT5.

[gunt]

Alot of the oem manufactures run dual injectors as it helps keep the intake valves from clogging up which is quiet an expensive fix and gets a brand a bad name , the DI injectors can easily keep up but the port injectors are only used in WOT even from low rpm