anyone with this regulator can you let me know which orfice you are using in ot and why? need some help please.....reason is that at idle car is dumping too much fuel making it rough at start up ....need to know if i have the right orfice size in the regulator.

 

I am using the largest orifice (on my turbo 1.6 EL) as a result of my Walbro 255 hp fuel pump. The best way to determine orifice size is to measure fuel pressure once you insert the orifice. Its a pain in the ***, but the only way to do it properly.