http://foreinnovations.blogspot.com/...el-sensor.html
I have run OE E85 Continental sensors in many builds - splitting the -8 (1/2") fuel feed line into dual -6 lines going to each rail and having sensor on one -6 feed line.
Long story short - even without splitting, unless making some very seriously big power numbers, the pressure loss through the sensor is much less than portrayed.
Of course, I am an engineer and from Missouri - so 'show me' data is how I like to operate!
Also - I am a HUGE fan of returnless systems using PWM pump control (Carl @ VaporWorx) and stagging pump(s) as needed for flow capacity. Solves so many issues and has worked flawlessly up to ~1800hp applications on E85.
Fuel pressure sensor (low pressure) should be mounted near the tank (fuel pump outlet) to minimize 'noise' in pressure of system from injectors. Reason OE's put them by fuel sending unit in tank. Flow losses from near tank to by engine increase with fuel flow rate (is actually calibrated into OE systems) but with well designed systems can be kept to very small loss - and no detrimental effects on engine operation.
David