ok i have a Vortec fmu 12:1, can i still use it? Anyone know where i can set the vafc to work with the fmu? t3 turbo, only pushing 7.5 pounds .5 bar. tial wastegate, I already have the resistors.
also, where should i set my timing

turboing a b16

 

AFC hack = NO FMU !!!

All u need is afc and larger than stock injectors, THATS IT. A search will yield loads of info on this.

 

sell your fmu. you don't need it.

 

What size injectors do you have? The AFC hack works strictly of the relationship between the size of the stock injectors and your new ones. For those running a 450 cc injector, AFC settings around -40% mimic the output of the stock injectors at negative manifold pressure.

For the FMU to "work" (i use the term loosely), you'll need a "Missing Link", or some check valves for the MAP sensor. People running the FMU setup do benefit from an AFC for tuning. However, don't count on your rings lasting long no matter how much boost you run with that setup. I would suggest selling it as well (even though you didn't ask for advice on that. )

 

I have personally used the fmu with missing link and vafc all together for 5,000 hard use miles. (dragstrip, high rpm freeway, etc.) boost was at 1 bar, injectors were at the time 550cc, and ran flawlessly,with no check lights, and no dyno tune. just the occasional fouled sparkplugs but a cheap fix at 13.00 a set no biggie always kept a set in the glove compartment.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by numba1 &raquo;</TD></TR><TR><TD CLASS="quote">I have personally used the fmu with missing link and vafc all together for 5,000 hard use miles. (dragstrip, high rpm freeway, etc.) boost was at 1 bar, injectors were at the time 550cc, and ran flawlessly,with no check lights, and no dyno tune. just the occasional fouled sparkplugs but a cheap fix at 13.00 a set no biggie always kept a set in the glove compartment. </TD></TR></TABLE>

your so full of **** its not even funny!!!! 176.4 psi of fuel pressure with 550's your car would litterally be so rich it wouldnt run. stop lying and try and help someone....

Landon

 

why would my rings not last long, do u mean cuz they are stock rings? or just cuz i'm boosing period? what should i sell? what do i do about my timing?


Modified by mp3albums2k2 at 6:15 AM 5/17/2004

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by fsp31 &raquo;</TD></TR><TR><TD CLASS="quote">What size injectors do you have? The AFC hack works strictly of the relationship between the size of the stock injectors and your new ones. For those running a 450 cc injector, AFC settings around -40% mimic the output of the stock injectors at negative manifold pressure.</TD></TR></TABLE>

i thought i had 440's but they arent labeled. im running from -36 at idle and -22 at wot. ughh..

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mp3albums2k2 &raquo;</TD></TR><TR><TD CLASS="quote">why would my rings not last long, do u mean cuz they are stock rings? or just cuz i'm boosing period? what should i sell? what do i do about my timing?.</TD></TR></TABLE>

im boosting only 6psi and im already hearing some slight detonation, i'd recommend something like a msd btm to retard the timing. but im personally getting rid of the afc to go with hondata.

Modified by mp3albums2k2 at 6:15 AM 5/17/2004[/QUOTE]

 

Using FMU together with AFC is NOT a hack Why do people not understand this?? It defeats the purpose of using the hack in the 1st place!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by swlabhot &raquo;</TD></TR><TR><TD CLASS="quote">Using FMU together with AFC is NOT a hack </TD></TR></TABLE>

Nah, it's pretty much a kludgy hack either way.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mp3albums2k2 &raquo;</TD></TR><TR><TD CLASS="quote">why would my rings not last long, do u mean cuz they are stock rings? or just cuz i'm boosing period? what should i sell? what do i do about my timing?</TD></TR></TABLE>

The rings will be killed by detonation. The problem with an FMU is it is just impossible to "fine tune" them at all. Someone mentioned running a 12:1 FMU at 1 Bar. As someone else mentioned, that equates to more than 170 psi of fuel pressure at the rail. Obviously, that's not happening. So, what happened to the "missing" 70 psi or more? Well, that's more than enough variability to make effective tuning impossible. I don't believe numba1 is lying, but that is definitely a risky fuel setup.

Sell the FMU. Buy some ~ 450 cc injectors (like DSM's). Manually retard the distributor (don't forget to jump the ecu), about 3 or 4 degrees. Set your AFC to -40% across the board, and start tuning from there with a wideband O2 sensor. Or better yet, try to figure out the Uberdata stuff (what I'm doing).