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DiGiTal66

Junior Member
what is Vafc? dont know what it is, i'd like to know what it does and where its at. thanx
 
Vtec Air Flow Converter

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It is a piggy back computer for adjusting A/R ratios and vtec engagement,it is located at your local speed shop,or on line.
 
Pissedoffsol (sorry if name is wrong man) said "another vafc hack job waiting to blow up :D" in a post in general about a turbo civic with 311 hp.

so what is the hack? and why does it have to blow up?
 
i think he was just saying that that turbod civic prolly wasnt tuned properly with the vafc.
 
Originally posted by RejecK@May 18 2003, 03:04 PM
Pissedoffsol (sorry if name is wrong man) said "another vafc hack job waiting to blow up :D" in a post in general about a turbo civic with 311 hp.

so what is the hack? and why does it have to blow up?


The "hack" makes it possible to tune the AFC for boost application without the help of a bypassed MAP sensor, such as the use of missing link or check valve. The theory is simple. MAP input is vital for the ECU to calculate fuel efficiency. The ECU constantly compensates to changes of the power plant through various sensors. What the AFC does is allow MAP reading manipulation while assisting the ECU on fuel enrichment per RPM status.....and there it is..... the AFC "hack" in the works. Unlike a Boost Dependent FMU which only provides fuel enrichment at boost condition, the AFC actually assists the ECU on fuel management at all RPM band. It lets the ECU compensate with the changes while the AFC is maniipulating the voltage output of the MAP sensor. It hides the "actual" true reading of the MAP but still lets the ECU thinks that the input is an actual reading. The problem with this AFC 'hack" is that, it has to set the fuel enrichment lean to avoid MIL/CEL with a MAP code. I guess it can be considered a hack because it is set up so no FMU or missing link is needed.
 
haha nice quote :)

basically what it comes dwon to, is that honda computers dont know what the fuck to do with boost. when it senses boost over 2 or 3 psi, it throws a code from the map sensor.

by running larger injectors, and tuning them DOWN to like -40% at idel, and so one, the vafc hack alters the voltage signal going to the ecu. so even though its seeing say, 10 psi, the -40% fuel curve drops it down under 2-3 psi, and thus doesn't throw a code.

its a hack, plain and simple.

it isn't great at fighting detonation, and it isn't great for tuning.
 
If your using the Missing Link, can you still use the Vafc? Is the Vafc worth 300? I was looking at hondatas and they look to be about the same price but it looks to be that you get more from the hondata?? Does the hondata completely replace the ECU or piggyback like the Vafc?

Thx in advance :blink:
 
does the vafc take the place of a boost guage and a/f guage?
and can you also adjust boost on it?

if so,

1) how much should i look to pay for one
2) is it reccomended to install it yourself?
 
Originally posted by karnash@May 18 2003, 06:28 PM
1) how much should i look to pay for one
2) is it reccomended to install it yourself?

I wouldn't pay more than $300,I got mine from Jason for $310 shipped :)

But it doesn't seem that hard to hook up,just grab some patience,wire cutters,soldering gun and basic tool set,and go.A couple hours maybe.
 
Originally posted by 92b16vx+May 18 2003, 12:34 PM-->
@May 18 2003, 06:28 PM
1) how much should i look to pay for one
2) is it reccomended to install it yourself?

I wouldn't pay more than $300,I got mine from Jason for $310 shipped :)

But it doesn't seem that hard to hook up,just grab some patience,wire cutters,soldering gun and basic tool set,and go.A couple hours maybe.

does it monitor boost and a/f?
and can you adjust boost with it?

on a greddy 15g kit that is....
 
Originally posted by karnash@May 18 2003, 06:48 PM
does it monitor boost and a/f?
and can you adjust boost with it?

on a greddy 15g kit that is....

A/F,not boost.No you can't adjust boost with it.
 
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