afc w/440s or fmu - Honda Forum / Acura Forum

ericwlws66 · 03-04-2004, 08:32 AM

going to install turbo soon but still undecided on best way to control fuel.
here is setup
99 b16a2 stock engine in 98 hatch
t3/t4 turbo only plan on boosting 5-6psi for now, fmic
255 intank already
stock fpr
br7ke plugs

I have some 440cc injectors already that came with the pieced kit.
I was going to get vafc to controll them, but then read that a FMU would be sufficient for 5-6 psi with stock injectors.
any help would be appreciated thanks.

lude_pwr · 03-04-2004, 05:55 PM

in my opinion fmu's are crap. u can't tune them and u risk ruining your motor. use your 440's and the vafc and tune it the right way and you won't regret spending a little extra money. it's been said time and time again that with proper tuning you can make more hp at the same boost level.

GreekSpeed · 03-04-2004, 07:01 PM

Both would run fine for low boost such as 5-8psi, but you have more adjustablilty with a AFC to get a little more power out of it.

ericwlws66 · 03-04-2004, 11:12 PM

ok i just found out that the fmu needs an inline pump.
i thought the 255 walbro would be good enough, but its more high voulme pump but cant hold the psi that the fmu wants.
So would i be ok to put an inline pump with the 255 in the tank.

DaWickedOne · 03-05-2004, 06:37 AM

Quote:

Originally posted by ericwlws66
ok i just found out that the fmu needs an inline pump.
i thought the 255 walbro would be good enough, but its more high voulme pump but cant hold the psi that the fmu wants.
So would i be ok to put an inline pump with the 255 in the tank.

you already have an in tank, you might as well just go with the afc and bigger injectors...

ericwlws66 · 03-05-2004, 08:09 AM

but damnit i dont wanna tune

ive only tuned dsm, and its it a lil easier b/c you have bigger starting point

anyone know what intial settings i should run?
i remember some
pressure sensor..6 in 6out, arrow up and to right
but i dunno how to do all the lo cam and high cam shit

the RAN · 03-05-2004, 09:23 AM

http://www.geocities.com/thermalfid16/VAFChack1.html

Shaun · 03-06-2004, 02:28 PM

Quote:

Originally posted by the RAN
http://www.geocities.com/thermalfid16/VAFChack1.html

I like !

, good info

GreekSpeed · 03-07-2004, 06:27 AM

who says u needed an intake fuel pump, or inline fuel pump to run an fmu?

i ran 7psi with just an fmu, and nothing else... and never had a single problem.

Wadzii22 · 03-09-2004, 03:46 PM

Why the Vafc hack is not good

if you are gona cheap out and not do it right then keep the fmu, just make sure to get a good wideband guage or fuel pressure guage inside the car so you will know when it breaks. the vafc hack will cause the timing to be way to advanced in lower boost

GreekSpeed · 03-09-2004, 11:54 PM

When it breaks?

i ran an fmu for over a year (about 20,000miles) with my jrsc at 8psi and had aboslutly no problems with it, and my motor is still in top condition.

if u tune the hack right u can easily compensate for the timing issues by adding more fuel if u get big enough injectors.

both fmu and hack are safe enough to run boost up to 8psi-10psi

Wadzii22 · 03-10-2004, 12:00 AM

the afc dosnt have load based corrections..... so you cant add fuel for load, only throttle position which dosnt always correspond to a boost level. read my post and then read it again, then attempt to understand whats going on. vafc hack is no good and WILL blow your shit up. you cant correct 10 deg of timing error with fuel..... it dosnt work and you will blow shit up...... see a trend here... vafc hack=blow shit up

fmu's do go bad. i have seen many break. hell i have delt with 4 or 5 that have broken on the dyno..... they dont always break, but i have seen enough go.. id be worried about it, spend the 120 bux for the fpr guage and piece of mind.

GreekSpeed · 03-10-2004, 12:14 AM

well my personal experience is all i have gone off of.... and i have had absolutly no problems with it.

as far as the hack goes... the whole point of the hack is to lower the voltage reading of the map sensor, and allow the ecu to read boost. by doing so with big injectors the ecu will try to compensate and add fuel as it can,...... and although the ecu obviously does not hacve any boost maps, it will add as much fuel as it can, which still would not be enough for a normal case.... but thats where the bigger injectors come in, and they will dump the compensated fuel...

(i am not the best at explaining this, but this is in a nut shell how the guy who discovered the hack years ago described it)

obviously the hack is not an exact science, but i know plenty of people that have been able to run 10psi very safe doing so..and that is the point.

and yes i agree with u on the piece of mind thing.