#23275, "RE: What disk to get for a s-fmu?" In response to Reply # 2
S-FMU comes with a variety of disks. An HRC stage 1 works well with the 2.72" diameter disk and dark colored spring. You will get nearly perfect fuel pressures with that combination.
Corbin
'95 ESI-T HRC+FMIC+ETC...
Gimme fuel...Gimme fire...Gimme that which I desire
#23277, "RE: What disk to get for a s-fmu?" In response to Reply # 0
Is the 2.72 disc the same as the 3.62 disc? Some peeps are saying to use the 3.62 disc with the dard spring for stage 1 at 5 psi?? I am getting a used S-FMU soon, and has the wrong disc in it, so what exactly do i need to keep my 80-90 boosted fuel pressure at 5 psi?? Please help! I don't know squat about this S-FMU or proper discs to use..sorry
13.5 @108 MPH-2.2 60ft(stupid FWD!) S16G @ 18 PSI/FMIC/Running on MegaSquirt II (Now with sequential fuel injection) My webpage: http://eclipsed4evr.home.comcast.net -1998 Mitsubishi Eclipse RS-T- "Toy" -1992 Plymouth Laser Turbo AWD(SOLD) -2000 Honda CR-V(daily)
#23278, "RE: What disk to get for a s-fmu?" In response to Reply # 5
2.72" disk is like a 5.4:1 ratio. 3.62" disk is like a 6.5:1 ratio. The 2.72" disk and dark spring work perfectly with a HRC at 6 psi. Your idle and full boost pressures will be perfect. It is a stretch to use the 2.72" disk and dark spring with a HRC at 9 psi. You have to raise the idle pressure way up to get the proper full boost fuel pressure. The 3.62" disk, silver spring, and a bleed valve work well with the HRC at 9 psi.
#23280, "RE: What disk to get for a s-fmu?" In response to Reply # 7
If you got 2 silver springs with your S-FMU, you have an old version. They recently stopped including the short silver spring and started including the short dark spring (it was optional). The short silver spring should give a lower actual gain than the longer silver spring. The dark short spring should give the highest actual gain. You want to lower the gain of the 3.62" disk for use with a HRC kit at 9 psi, so try the short silver spring. If you can't get your idle pressure high enough (40-50 psi), then try the long silver spring. If that still won't let you get the idle pressure high enough, use the short dark spring. You may need to get the bleed valve to lower your fuel pressure at max boost.
Corbin
'95 ESI-T HRC+FMIC+ETC...
Gimme fuel...Gimme fire...Gimme that which I desire