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Forum nameTurbo/Nitrous Tech
Topic subjectGuys with SFMU, need your advice.
Topic URLhttps://forums.2gnt.com/dcboard.php?az=show_topic&forum=i8&topic_id=37008
37008, Guys with SFMU, need your advice.
Posted by Nitrous_RS1997, Jan-06-03 01:58 PM
I dont know very much about the Vortech SFMU at all(never had one, ive got something like it that the guy who made my intercooler builds). anyways, we just finished a rebuild of a 97 Clipse, and he has already bought a SFMU. he has 30lb injectors for now, and he wants to run 12psi. also have a SAFC for fine tuning, just like on mine. my question is, what do you guys think we should set the idle FP at for this particular set up? he has a regular vortech FMU installed right now(that came with the STAR lot), is the hook up of the SFMU pretty much the same? if not, what all is different? and does it come with the adjustment springs/disks? cause i know you have to buy em for the regular FMU. anything else he will need to get with the SFMU for it to work properly? thanks for putting up with my dumb questions, for all the other crap ive done, im a newbie to the SFMU. thanks guys.



www.TeamKLR.com
1997 Silver RS
12.3@118mph,20psi, race gas(drag radials)
Wiseco 10.5 Pistons
Eagle Rods
Started as a manufactured turbo kit, now its a custom one!
Greddy Exhaust
440cc Injectors

Waiting on the EVOlution!
37009, RE: Guys with SFMU, need your advice.
Posted by JasonESi_T, Jan-07-03 01:11 AM
also have a
>SAFC for fine tuning, just like on mine. my question is,
>what do you guys think we should set the idle FP at for this
>particular set up?

I think it might be pretty low from listeng to other guys, bu I would just start out at stock levels (47 psi) and work from there. This is a situation where a datalogger would be EXTREMELY valuable. He would be able to look at the fuel trims at idle and see what the ecu was doing to lean ou things. You want to have the fuel trims at close to 0%.

he has a regular vortech FMU installed
>right now(that came with the STAR lot), is the hook up of
>the SFMU pretty much the same?

It's almost exactly the same. However, you can remove the stock FPR as I imagine he still has the hooked up since the FMU can not control that. I recommend installing the SFMU in the engine bay close to the fuel return line at the fuel rail. If he doesn thave one, fabricate one with some fuel injection line, and some hard fuel line to run under the car to some more fuel injection line at the return port at the fuel tank assembly. All of this will depend on what year car he has though. If it's a 95, you won't need to do any of the above. If he has a 96+, then he'll need to go buy a few things.

and does it come with the adjustment
>springs/disks?

Yes it does. It should come with a variety of springs and disks. You'll need to figure out which disk and ring he'll need to set up his boosted fuel ratio, but I would guesss somewhere close to the 5:1 or 6:1 combination. There are particular disks/rings that have that ratio.

The SFMU also comes with some springs. A light colored and a dark colored spring. With stock injectors, the dark colored spring is used. Go with the spring that gets you to your desired idle fuel pressure. This may take some trial and error, as with all of the tuning.

As has been said many a time here, every car seems to have different fuel needs, so it's best to use your own educated judgment through trial and error with the use of a datalogger and appropriate gauges.

cause i know you have to buy em for the
>regular FMU. anything else he will need to get with the SFMU
>for it to work properly?

He may perhaps need the abovementioned fuel lines and possibly some Aeroquip fittings for proper connections. But again, this will be specific to your application.

Check out the "search" option in this section. "SFMU" or "Vortech" should get you all the information you need for other people's tuning experiences and informational exchanges.