pressure regulator
What other mods do you have? Is your car tuned? With flash, etc? Seems that the increased flow of the Walbro does tend to fatten up the fuel curve.
On a Buick GN I used to own, one would have an Eprom chip burned and then fine tune the fueling with the adjustable fpr. In fact, with Buicks the adjustable fpr was probably the most essential tuning device. At the track one would do a base run and then lean out(lower) the fuel pressure until the point where knock was detected(-2*).
On race gas the ideal FP was usually btwn. 36-38 psi. On the street and on pump gas most guys ran btwn. 40-44 psi. By leaning out the fuel pressure at the track one was usually rewarded with an increase in trap speeds.
Kind of an unsophisticated approach, but back in those days it worked for those who couldnt afford a standalone. With Evos however, I havent seen a widespread use of the adjustable fpr´s. I do miss not being able to tinker with the fuel pressure.
As a mater of fact, on my Buick I had a staged, double Walbro fuel pump setup, wherein the second Walbro would kick in via a Hobbes switch at the desired boost level(say 18 psi). So you could adjust the volume as well as the pressure. Sorry, for rambling OT.
On a Buick GN I used to own, one would have an Eprom chip burned and then fine tune the fueling with the adjustable fpr. In fact, with Buicks the adjustable fpr was probably the most essential tuning device. At the track one would do a base run and then lean out(lower) the fuel pressure until the point where knock was detected(-2*).
On race gas the ideal FP was usually btwn. 36-38 psi. On the street and on pump gas most guys ran btwn. 40-44 psi. By leaning out the fuel pressure at the track one was usually rewarded with an increase in trap speeds.
Kind of an unsophisticated approach, but back in those days it worked for those who couldnt afford a standalone. With Evos however, I havent seen a widespread use of the adjustable fpr´s. I do miss not being able to tinker with the fuel pressure.
As a mater of fact, on my Buick I had a staged, double Walbro fuel pump setup, wherein the second Walbro would kick in via a Hobbes switch at the desired boost level(say 18 psi). So you could adjust the volume as well as the pressure. Sorry, for rambling OT.