OK guys.
I am currently running stock injectors with SFMU and walbro 255HP.

And I know my static and idle should be 50PSI and 45PSI respectively.

But tonite, I just went out to try to change the fuel pressure (for the idle) and I can't.

How do I do it? currently it is at 55PSI for idle. using silver spring and largest disk.
I tried to turn the vaccum bolt on the lid of the SFMU to tighten and lose each way for 2-3 turns...but I do'nt see the fuel gauge pressure changes AT ALL (I waited too)... stay at 55PSI. should I turn more?

Thanks guys.
Gil

do not adjust the vacuum bolt. you want to adjust your fuel pressure with the static adjuster on top.

and for those that don't know, he is not turbo'ed

when you get that turbo on, you are going to want the dark hard spring installed.

Sup WIkki...
I am confused.

The SFMU manual said the screw on top lid (the vertical standing one with a NUT to lock it.... it said it use to set the "STATIC" pressure...and I have to use the vaccum to adjust the idle pressure?

SO what should Ido? I changed the setting of the vaccum nut....what can I do to make it back? and how do I change the idle pressure?

Please help.

I "believe" that the vacuum adjuster is just seated fully inwards. be cautious because I have not tried this my self. do not over tighten it.

to adjust your fuel pressure you want to loosen the nut on top and turn the allen
the changes should be immediate. you should not have to wait any time at all.

I just went out to try out the screw on the top like you said....
and I can ONLY make the fuel pressure HIGHER...making my idle pressure over 60PSI....what should I do?
I can't make it lower....HOW??? I can't do it....???
I am totally lost now.
I do'nt get how the SMFU works to tune..... x( :nono

gil

sorry, lets try this again. it is not posting my full messages.



wtf!
my messages are cutting off when I post them!

I "believe" that the vacuum adjuster is just seated fully inwards. be cautious because I have not tried this my self. do not over tighten it.

to adjust your fuel pressure you want to loosen the nut on top and turn the allen screw on top (if I remember correctly) counter-clockwise about one full turn, and then check your pressure. I would keep the vacuum hose connected, and adjust for Idle pressure only.

the changes should be immediate. you should not have to wait any time at all.

OK.... I do'nt konw...coz I tried that....counterclockwise..but I am thinking.
when the SFMU comes...that screw is already about 1 inch sticking out from the top lid....
if I continue to turn it outward.... how much further???
I do'nt want it to get to the end, and fall out or damage something.

So what should I do? Just keep turning it counterclockwise till it get to 45PSI for idle?

Gil

IMO,
if it doesn't change after one full turn, then there is something else going on. read this thread.

http://forums.2gnt.com/dcboard.php?az=show_topic&forum=8&topic_id=56240&mesg_id=56240&listing_type=search

I'm the search masta!:thumbsup

does anything come to mind?

oops! it is this thread.

http://forums.2gnt.com/dcboard.php?az=show_topic&forum=8&topic_id=56240&mesg_id=56240&listing_type=search

Tightening the STATIC bolt on the top lid of the SFMU will increase fuel pressure. If you can't get the static pressure low enough (by turning the screw in a manner so that you see more of it and it is turning out of the SFMU lid), try a different spring. If you are still having trouble, check your vacuum lines. If you are still having trouble lowering them, check for an obstruction in the return line. As you can imagine, if the fuel can't flow fast enough back to the tank, obviously the fuel is going to pile up in the fuel rail and keep your pressure higher than desired. Keep us posted, and good luck.


1996 Eclipse RS / 5-Speed / Aerogear Body / Coated in Magnetic Red Metallic rev.2 / T3 Turbo Intercooled @ 8 psi / More at http://home.insightbb.com/~mgalyan/
Mark Galyan - Indianapolis, Indiana

^^^^^ :thumbsup

if I remember correctly if you have the stock fpr still in place you will not be able to lower the fruel pressure. did you take out the stock fpr?

Hi guys...yes I disabled the Stock FPR.

OK....so I should change to the black spring then correct?
If I change it to the Black Spring. my idle pressure will drop then I can start tighten the screw to make the idle pressure back up to 45PSI?

And one question. I want to play safe and ge a good injectors that will give GOOD enough fuel even after I rebuilt and aim for 12-13PSI.

should I get 30lb/330cc injectors? higher? do I need to get AFC or whatever if I buy injectors larger then 330cc injector?

THanks.
GIl


*EDIT* One question, "for example": If I keep my exact current setup with the exact same spring, screw prosition etc.... for now I am at 55PSI stock injectors. if I put in a bigger injectors and DON"T CHANGE any SFMU setting...will the PSI drop right away? how much?

THanks.

The 310cc injectors work great up to about 13-14 psi, but above that you will want bigger ones. I sorta wish I had bought bigger ones, but they are cheap and I'll pop some 440's or bigger in when I rebuild the motor later next year when the funds are around for me. When you run bigger injectors, you will have to make some adjustments on the SFMU. For example, I've experimented with the biggest disc and the 2.72" disc, and I've found that the 2.72" disc does cause me to run too lean. The biggest disc caused a super rich condition and made the car studder in boost. The only way I was able to remedy the situation was to set up a bleed valve system to relieve a little boost from the SFMU. I did a writeup on it not too long ago. Check it out, it's cheap too.


1996 Eclipse RS / 5-Speed / Aerogear Body / Coated in Magnetic Red Metallic rev.2 / T3 Turbo Intercooled @ 8 psi / More at http://home.insightbb.com/~mgalyan/
Mark Galyan - Indianapolis, Indiana

http://www.vortechsuperchargers.com/pdf/manuals/superfmuim.pdf Go here this may be more helpful.