billk2k

My big question is that I dont know when I dont need it anymore. I have a Walbro 255 HP fuel pump w/ AEM Fuel Rail AND FPR running at 40psi (until tuning) and VTEC Controller (untuned). I still have the stock JDM injectors on the car but am soon replacing them with some 550's. At what point would the FMU be unnecessary. Thanks for any input!

inspyral

You don't need an FMU w/ 550cc injectors. You also porbably won't be able to use the AFC hack with 550s.

Muckman

iTrader: (2)

I have a brand new Vortech 12:1 FMU for sale if anyone wants one

billk2k

Well I plan on getting a standalone unit eventually, but I have heard that 550's can be tuned through the VAFC. So touching base back on the first question, can I actually get rid of the unit now while running the stock injectors?

inspyral

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by billk2k &raquo;</TD></TR><TR><TD CLASS="quote">Well I plan on getting a standalone unit eventually, but I have heard that 550's can be tuned through the VAFC. So touching base back on the first question, can I actually get rid of the unit now while running the stock injectors?</TD></TR></TABLE>
If you're running stock 240cc injectors, you need an FMU.

As for the 550s, the largest injectors you can run with the hack is ~450cc. Anything larger and your idle will be pig rich(er) since you have to set the AFC to -40% correction to idle 450s, and the 550s flow 100cc more per. Keep in mind the - correction on the AFC maxes out at 50%, which I doubt will yield a very good idle with 550s.

billk2k

That's ahhh...that's ah pretty gewd. I am still very new on this whole fuel/tuning thing. I am hoping to get the fuel situated and put down some decent numbers soon. Thanks!

ILLICON3000

[QUOTE=inspyral]You don't need an FMU w/ 550cc injectors. QUOTE]


Don't listen to this ASSHAT He's just another dumb keyboard tuner....There are tons of people who use 550 injectors with FMU's all day long.

Why swap out 550 injectors for 880's and have to worry about wiring in a resistor box, etc when you can just run an FMU instead?? Dummy

inspyral

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ILLICON3000 &raquo;</TD></TR><TR><TD CLASS="quote">[QUOTE=inspyral]You don't need an FMU w/ 550cc injectors. QUOTE]


Don't listen to this ASSHAT He's just another dumb keyboard tuner....There are tons of people who use 550 injectors with FMU's all day long.

Why swap out 550 injectors for 880's and have to worry about wiring in a resistor box, etc when you can just run an FMU instead?? Dummy</TD></TR></TABLE>

When did I ever say I was a tuner? He asked if he could use his 12:1 FMU with 550cc injectors. Are you saying he should do that? If so, you need to revauluate just who is the "ASSHAT"

kgibson16

12-1 fmu and 550s wont work, u at least need to change the pill in the fmu and still the car will sputter, just keep the fmu 12-1 with stock injectors with a 255 pump that ***** good for a solid 10psi

ILLICON3000

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by inspyral &raquo;</TD></TR><TR><TD CLASS="quote">

When did I ever say I was a tuner? He asked if he could use his 12:1 FMU with 550cc injectors. Are you saying he should do that? If so, you need to revauluate just who is the "ASSHAT"</TD></TR></TABLE>

You're the keyboard tuner...giving FALSE tuning advice on a subject that you have no experience with. Ask the owner of Inline Pro if you can run an FMU with 550's...or just look under his hood

kgibson16

dude the car definitly wont run right with 550cc and a 12-1 fmu , the owner of inline pro probably runs a way smaller pill like 4-1.

DSF

Geez.

Yes, you CAN run 550s or whatever size injectors with a rising rate FMU. No, you may not NEED to, however, with your setup. Until you list exactly what you are working with engine/turbo-wise and what your goals are <U>no one</U>, can tell you what you must/have/need do.

If I recall, this is the internet, so all of us are currently keyboard tuning. And yes, I too am an asshat. I just have temporarily misplaced my membership card.

billk2k

So aside from using the 550's with the Vortech FMU, is it still possible to use them with the VTEC controller, or would changing them require a standalone unit? My current setup is in my sig. All stock internals and wastegate set at 5 psi.

inspyral

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ILLICON3000 &raquo;</TD></TR><TR><TD CLASS="quote">

You're the keyboard tuner...giving FALSE tuning advice on a subject that you have no experience with. Ask the owner of Inline Pro if you can run an FMU with 550's...or just look under his hood</TD></TR></TABLE>
Again, you miss the point of this thread. He asked if he would be able to use his existing 12:1 FMU with 550cc injectors.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by billk2k &raquo;</TD></TR><TR><TD CLASS="quote"> At what point would the FMU be unnecessary. </TD></TR></TABLE>

As for the owner of Inline Pro, if he's running an FMU with 550s, I highly doubt it's a 12:1.

As for my having no experience, I ran a 12:1 FMU with stock injectors and an inline pump for several years. I also ran the hack with 450s for a year, so don't tell me I have no experience with turbos, FMUs, or plus-sized injectors, and certainly don't accuse me of giving false information.

ILLICON3000

there's no reason why he couldn't use his existing FMU.

Ya he does....he runs consistent high 11's on street tires..Turbo S2000

and You did what was conventional....I had an FMU, RC440 AFC, and my car had more torque than it does now..alot more.. I ditched the FMU and got a 255 and got tuned..It pulls much harder after 5k rpm but also I'm running 8 with 10 pound spike..but the torque isn't there. My point here is that it can be done....and what's popular isn't necessarily the best... (as in my case I lost alot of torque and my turbo spools way slower as well by tuning, another popular thing people like to splat around) and that you can run 550's with an FMU and get em to run like 880's.


To give you a concrete answer the FMU isn't NECESSARY with 550 injectors...HOWEVER it is a great fool proof method of ensuring that proper fuel gets to your motor (IE rev limiter, ecu cuts fuel).. and also for higher boost applications if you don't wanna have to run gigantic injectors.

DSF

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by billk2k &raquo;</TD></TR><TR><TD CLASS="quote">So aside from using the 550's with the Vortech FMU, is it still possible to use them with the VTEC controller, or would changing them require a standalone unit? My current setup is in my sig. All stock internals and wastegate set at 5 psi. </TD></TR></TABLE>

It's really going to be up to your personal preference and to your tuning. With only 5psi on the stock DRAG turbo, the 550s alone should be fine. If you upped your HP goal or maybe wanted to run a lower base fuel pressure, then you should be fine with keeping the FMU. I don't think you would want the 12:1 disc in there, however. A 4:1 up to an 8:1 if necessary would suffice. I mentioned running a lower base fuel pressure because I have seen on some vehicles that running the hack with 550s there can be trouble with idle. Some are fine with 550s, some aren't.

kgibson16

My current setup is in my sig. All stock internals and wastegate set at 5 psi.

who cares what inline pro runs, the kid runs 5 psi not 20 psi . not everone is building something to try to go the fastest. stock injectors 12-1 fmu and 255 pump is fine for 5 psi