I hate my damn SFMU! I cant seem to lower the fuel pressure down to a respectable number.

From what I have seen from searches, and heard, I am supposed to take the vacuum hose off the the barb on the top to set the "static" pressure. SO I took the vacuum line off and turned the allen/screw thing in the top of the SFMU to where it is almost all the way out, BUT STILL NO PRESSURE DROP!!! WTF!!! I am running around 40psi at idle according to the gauge mounted to the test port on my fuel rail.

Am I doing something wrong?????? Please help, I am trying to go to the Shootout but my gas mileage sucks right now.

BTW I have the 2.22" ring and disk with the small ( silver ) spring. I also have 415cc injectors.

Any suggestions?

Leave the vac line hooked up when setting your pressure. With your injects, you should idle around 16-18 psi. You do need the longer, silver spring in it too, the one that factory ships with the SFMU, as this spring lets you idle at much lower fuel pressures. You may want to put in the next largest disk too, just to be safe..start out rich, then go from there..

you can do it his way ^^^ or redo what you did, but once you unplug the vacuum line to the super fmu block the vacuum going to the intake manifold with something ( to stick in ) and then adjust your static fuel pressure. also you still might have to use a different disk/ring if what i said does not get you low enough.
good luck
Michael
99gs (broken) Motor being built now
HRC Stage 2 8-Injector Setup
Fully Built by July 25,2003 hehe
2GNT Member #32

Does the smaller the disk and ring make for a richer or leaner overall condition. I thought the bigger injectors you have the smaller the ring and disk combo.

I will try it again and let you know the results.

small disk/ring lowers the rise rate ( gain )

Michael
99gs (broken) Motor being built now
HRC Stage 2 8-Injector Setup
Fully Built by July 25,2003 hehe
2GNT Member #32

Don't worry bro your on the right path. I still don't have any extra fuel over stock, so I'm damn near 3000 miles on this motor and can't get on it. Try what they said about lowering the idle pressure first. (leave the Vac line hooked up and lower the pressure) then move to the static pressure, and so on. I have already realized there is no way for me to get to the shoot out, and it sucks. Keep at it bro your almost there.

So do you have the short/dark spring in, or the longer/silver spring in? you should use the long/ silver one to lower pressure.
www.TeamKLR.com
1997 Silver RS
Wiseco 8.8:1 Pistons(back to low compression!)
Eagle Rods
T3/T4 Turbo
Custom FMIC
Greddy Exhaust
440's
Most current 1/8th mile time: 8.3@90mph 2.015 60'(Nitto Drag radials, i suck)

I have the long Silver spring in the SFMU right now with the 2.22" ring and disk combo. The ring and disk DO go UNDER the diaphragm right? Thats how I have it assembled.

I will try again tomorrow and see what I can come up with.



Kirby....thanks for the support and encouragement. I am almost at wits end with this car right now. One thing after another. Sucks thay you cant make it to the Shootout. I had a blast last year and have been looking forward to it since the day it ended.

Yeah, the disk, then ring around the disk, then the diaphram, then the spring retainer, then spring, then the other spring retainer, then the top lid of the SFMU. Be sure the SFMU bolts are not overtightend, or not loose, and be sure the diaphram is centerd and not kinked, ect..Tighen the bolts snugly, dont hammer em down..

hmmm...goodluck curing your problem. but i use the 2.72" disk to start out with. it should be the correct one for the size injectors you have. and you will most likely need to get the optional bleed valve to lower the boosted fuel pressure a bit.
www.TeamKLR.com
1997 Silver RS
Wiseco 8.8:1 Pistons(back to low compression!)
Eagle Rods
T3/T4 Turbo
Custom FMIC
Greddy Exhaust
440's
Most current 1/8th mile time: 8.3@90mph 2.015 60'(Nitto Drag radials, i suck)