i am runnin a 310 cc injectors w/ a walboro 255 pump and a 12:1 FMU disc. some people ahve told me that this will be too much fuel during idle.

is this troo and if so what should i set the fuel pressure @ idle for on my FPR.

 

just bump down the 12:1 to a 10:1 and you should be good. I've heard people use the 8:1 but to be safe just use the 10:1.

 

do u have any kind of afc? if so then that will solve that issue..the fmu will not affect the idle..

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by bruceleeroy &raquo;</TD></TR><TR><TD CLASS="quote">do u have any kind of afc? if so then that will solve that issue..the fmu will not affect the idle..</TD></TR></TABLE>
but the bigger injectors will.

 

310cc injectors is commonly used with an 8:1 fmu disc, and it generally still will run a bit rich. but it also does depend on how much psi u will boost.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by J337_UNIT &raquo;</TD></TR><TR><TD CLASS="quote">310cc injectors is commonly used with an 8:1 fmu disc, and it generally still will run a bit rich. but it also does depend on how much psi u will boost.</TD></TR></TABLE>

7 psi off the wastegate

 

did you get those injetors and fmu on ebay?/

 

no the injectors are RC's bought from the shop i werk at and the FMU 12:1 disc came with the revhard kit.

 

I sold somone my 310's and 12:1 fmu with a vafc in jersey. But When I had it on my setup/ i was a tad rich at idle but not over rich. That was because of the injectors and not the fmu.

 

You'll need an AFC to get it to idle.

I ran this setup for about 2 years with a 10:1 disc. I ran good. I recently changed to 450cc and AFC and it runs like crap...so, ya....what ever...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Haberdasher &raquo;</TD></TR><TR><TD CLASS="quote">You'll need an AFC to get it to idle.

I ran this setup for about 2 years with a 10:1 disc. I ran good. I recently changed to 450cc and AFC and it runs like crap...so, ya....what ever...</TD></TR></TABLE>

so u ran a 10:1 disc w/ 310cc's and ran fine? isnt 10:1 a tad more rich?

 

before my vafc I just had the 310 with jrsc fmu on my previous setup and it idled fine for 2 years. You don't need a vafc to idle 310's.

 

do you have an inline pump too?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by BoM &raquo;</TD></TR><TR><TD CLASS="quote">
but the bigger injectors will. </TD></TR></TABLE>

no kidding.. ..thats why i said he needed an afc ..i was replying to the guy who said he needed a smaller fmu diaphram..

 

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

no kidding.. ..thats why i said he needed an afc ..i was replying to the guy who said he needed a smaller fmu diaphram..</TD></TR></TABLE>

so you are sayin to use a afc with a FMu????? isnt that the whole point of hacking to get rid of the FMU?

 

if u have access to one...sure why not?..thats why i asked..it will solve your rich idle with the 310s...with ease

 

people have run 310-370s with fmu for years its not an uncommon thing..

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by bruceleeroy &raquo;</TD></TR><TR><TD CLASS="quote">if u have access to one...sure why not?..thats why i asked..it will solve your rich idle with the 310s...with ease</TD></TR></TABLE>

so then i wouldnt have any use for the FMU correct?

 

depending on how much u are boosting.. no...

 

only about 7 psi

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by kobi2002 &raquo;</TD></TR><TR><TD CLASS="quote">before my vafc I just had the 310 with jrsc fmu on my previous setup and it idled fine for 2 years. You don't need a vafc to idle 310's. </TD></TR></TABLE>

what compression was this motor, what ecu (chipped/stock), and what fuel pressure...?? idled 310s fine?...hmm interesting

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by bruceHungLO &raquo;</TD></TR><TR><TD CLASS="quote">only about 7 psi</TD></TR></TABLE>

well from what u are telling me u probably dont need the 310s..u can probably just run the fmu or just 310s and afc...your choice..

 

Ok, here's the deal....

If you are using 310/320cc injectors you need the FMU and AFC. You need the FMU because the 310/320cc injectors have the same problem as the stock injectors. They can't provide enough fuel by themselves when boost comes in. So you need to add fuel pressure as boost pressure rises. The 310/320cc injectors are 33% larger than stock, but the ECU will try to run them like they are 240cc. The result is a very very rich mixture at idle, almost to the point that it won't idle at all. So you use an AFC to compensate for the larger injectors.

 

What happened to using uberdata? I've seen you on the forum.

What do you do at Stage 2?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Mad Cow &raquo;</TD></TR><TR><TD CLASS="quote">What happened to using uberdata? I've seen you on the forum.

What do you do at Stage 2?</TD></TR></TABLE>

uberdata will be done later on for the time being gettin her running ill be running FMU. i will mostl likely be taking it to jeff (aka boosted-hybrid) for uberdata tuning once more money comes my way. as far as what i do at the shop i run the sales floor. anything ordered or sold most likely is done by me or the one owner.

yes it does seem like i am askin alot of questions namely because ive always been a all motor kinda guy. but since i havent done a turbo, and everyone @ the shop is basically turbo i am tryin to keep up and while doing that i am learning more and more about turbo so i can have knowledge. i figure the best experience is doing it not reading so i am just asking suggestions.