So in doing some research on this site and team-integra.net. I relized that my cars running a little rich due to the bolt ons. If I get a vafc II I should be able to correct this right? Tell me what you guys think about it. Planning on ordering it ASAP. Just wanna run it by you guys first. 00 GSR by the way.

 

bump

 

I had my VAFC II in my 94 GSR, also some of the guys have the VAFC in an 95, 96 and 97 GSR, and my final thought on them is just to get a Hondata system. I mean its great and everything. I love it, but my problem was that when I ran in against a stock ECU it will throw out a check engine for a VTEC problem, so I had it in, but always had to leave it on defult. Now the guy with 95 GSR had to dyno his car and come to find out that he need to rip out his. I means to get the max out of your VFAC you have to dyno it, but when you get to the dyno, mostly everyone recommands Hondata. Plus most of the time Hondata is cheaper and less open. If you leave your VAFC out near your shifter or near your radio, people then to break into your car thinking you have crap to steal. YES THIS HAPPEN TO ME!!!

 

bump any other thoughts. Will I definetly throw a cel with vafc 2? If i get HONDATA dont I also need an OBD1 ecu w/ conversion harness and a skunk 2 or similar manifold. because the p28 will not run secondaries on a GSR. I Can get VAFC 2 for a little over $200. Somone let me know what a good option is and what to get. Also everything I need to know. I want to get the ball rolling on this ASAP. Thanks in advance guys.

 

hey guys, can u guys tell me what running rich mean ? n wat the other beside rich? wat does it mean to run rich? sorry 4 asking.. cus i seriously dont know.

 

Running Rich mean you have too much fuel in the motor and not enough air. It's won't do too much damage vs. running lean. But after a while the motor will feel the effect. 14.7 a/f ratio is storch(or normal) but when you full throttle you need more fuel vs air in the engine. A turbocharge, supercharge, or nitrous need somewhere 11.5 a/f ratio to 12.5 a/f ratio depend on how much boost they're running.

 

For the First question. VAFC is basicly a hack on you ECU. VAFC is useless unless you have Force induction. VAFC is good for beginner who want some control of the motor and fairly easy to tune. But it also mess up your torque curve. A stock ECU have a normal fuel map and you are basiclly hacking it and changes the whole fuel map. With Hondata and AEM EMS you can do more because you are a standalone. You can finner tune you car with standalone vs. VAFC. Time to tune you care VAFC 30min-1 hour. Standalone 4-6 hours. Tune cost $50-$75 hr. So unless you have turbocharge your stock car this is useless!!!

 

Though the fact remains that the car is running rich and needs to be fuel tuned. Anyone else have some more in depth info for me?

 

From what i understand the VAFC is a great tool to do some basic tuning. If you took your car and tuned it with the vafc and dynoed it lets say you got 150hp, well if you did a full uberdata or hondata you might be able to gain a few HP and you would be able to work on the power curve.

For simple bolt on's I/H/E you should not need to tune. If you are running rich you might want to first see if you are throwing any codes, check you plugs/cap/rotor do all the basic maintance first. Ypu might have a sensor going bad and that is causing you to run rich. If this is the case the VAFC will only act as a band-aid.
Once you put cams, or start to do head work that is the time you really need a VAFC or other tuning device.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Racermech &raquo;</TD></TR><TR><TD CLASS="quote">For simple bolt on's I/H/E you should not need to tune. If you are running rich you might want to first see if you are throwing any codes, check you plugs/cap/rotor do all the basic maintance first. Ypu might have a sensor going bad and that is causing you to run rich. If this is the case the VAFC will only act as a band-aid.
Once you put cams, or start to do head work that is the time you really need a VAFC or other tuning device.</TD></TR></TABLE>


Thinking the same thing. You should be running lean if anything if you added I/H/E because youre adding more air and expelling it faster. Check your O2 sensors and your Smog equipment to make sure its running properly

 

The ECU normally sees a certain amount of air, so it adds fuel. The problem with I/H/E is that it adds more air, in turn telling the ECU that the motor is running lean(more air,not enough fuel at the O2 sensor) so the ECU sees this and adds more fuel to overcompensate for the added air. So then you run rich.
A vafc just takes certain points over the rpm range and adds or subtracts fuel. Tricks the ecu really. Works, but is not really effective. I was gonna get one till I realized what they really did.
Good luck though.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by honda1982 &raquo;</TD></TR><TR><TD CLASS="quote">VAFC is useless unless you have Force induction.</TD></TR></TABLE>
And it's even more useless when you add forced induction to an engine/engine management system that didn't originally have it.

It's a moderately ok solution for OEM supercharged vehicles, but it approaches uselessness when you swap out the supercharging units with different ones.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by honda1982 &raquo;</TD></TR><TR><TD CLASS="quote">But it also mess up your torque curve.</TD></TR></TABLE>
Umm...right.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by honda1982 &raquo;</TD></TR><TR><TD CLASS="quote">A stock ECU have a normal fuel map and you are basiclly hacking it and changes the whole fuel map.</TD></TR></TABLE>
Changes the WHOLE fuel map, huh? Last time I checked, AFC's can't read and write to and from the ROM. Through an AFC, you can change the MAP input voltage and as a result alter the ignition and fuel outputs, but it definitely doesn't change the fuel or ignition base maps.

Most of the other stuff you said, I can't find enough wrong with the statements to argue against them. So, you're good there.

As for the whole running rich thing, you should use a more accurate and consistent means of measuring what the air:fuel mixtures are than guessing at it and saying, "Hey, you know what Bob....that looks rich to me." Use a lambda meter that employs a wideband UEGO sensor to check your fuel mixtures under various operating conditions.

You can also use certain scan tools to look at the STFT's and LTFT's to see how much the oxygen sensor feedback is trying to correct back to hit it's target fuel mixture.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Racermech &raquo;</TD></TR><TR><TD CLASS="quote">From what i understand the VAFC is a great tool to do some basic tuning. If you took your car and tuned it with the vafc and dynoed it lets say you got 150hp, well if you did a full uberdata or hondata you might be able to gain a few HP and you would be able to work on the power curve.

For simple bolt on's I/H/E you should not need to tune. If you are running rich you might want to first see if you are throwing any codes, check you plugs/cap/rotor do all the basic maintance first. Ypu might have a sensor going bad and that is causing you to run rich. If this is the case the VAFC will only act as a band-aid.
Once you put cams, or start to do head work that is the time you really need a VAFC or other tuning device.</TD></TR></TABLE>

Brand new cap wires plugs and rotor. No codes. I just want to know that the VAFC 2 will help lean it out a little.

 

If it really is the STFT and LTFT that are causing it to run rich at WOT (from the carryover LTFT), then you need to fix the problem at the root rather than only trimming the WOT fuel back or, God forbid, simply leaning out everything. WOT driving only makes up a small percentage of your driving (I hope). If you lean out the part throttle conditions when it's already too lean, then you'll only increase the amount of positive oxygen sensor feedback and make it add more excess fuel under WOT conditions.

You'll need to have an accurate way of measuring the STFT and LTFT so you can see when you've hit a target of +/-0%. For that, you'll need a scan tool that can read the STFT and LTFT.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by DC2_005200 &raquo;</TD></TR><TR><TD CLASS="quote">I had my VAFC II in my 94 GSR, also some of the guys have the VAFC in an 95, 96 and 97 GSR, and my final thought on them is just to get a Hondata system. I mean its great and everything. I love it, but my problem was that when I ran in against a stock ECU it will throw out a check engine for a VTEC problem, so I had it in, but always had to leave it on defult. Now the guy with 95 GSR had to dyno his car and come to find out that he need to rip out his. I means to get the max out of your VFAC you have to dyno it, but when you get to the dyno, mostly everyone recommands Hondata. Plus most of the time Hondata is cheaper and less open. If you leave your VAFC out near your shifter or near your radio, people then to break into your car thinking you have crap to steal. YES THIS HAPPEN TO ME!!!</TD></TR></TABLE>

My VAFC II manual did not have the VTM hookup in the wiring diagram... threw a code 22 after adjusting the VTEC crossover point. Defintley need to hook this up for USDM ECU's... JDM ECU's do require the VTM hookup. Still haven't emailed APEXI USA to let them know there is an error for OBD2a Integras... plan to get this info to them soon so others can problems solve this.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by IN VTEC &raquo;</TD></TR><TR><TD CLASS="quote">If it really is the STFT and LTFT that are causing it to run rich at WOT (from the carryover LTFT), then you need to fix the problem at the root rather than only trimming the WOT fuel back or, God forbid, simply leaning out everything. WOT driving only makes up a small percentage of your driving (I hope). If you lean out the part throttle conditions when it's already too lean, then you'll only increase the amount of positive oxygen sensor feedback and make it add more excess fuel under WOT conditions.

You'll need to have an accurate way of measuring the STFT and LTFT so you can see when you've hit a target of +/-0%. For that, you'll need a scan tool that can read the STFT and LTFT.</TD></TR></TABLE>

If you're goona use non standard acronmys than you should explain in your posting...STFT = short term fuel trim.... LTFT = long term fuel trim.

STFT and LTFT are always governed by feedback and calculation are made by the by the ECU to determine these values. VAFC cannot change these...the ECU will compensate using fuel trim for whatever VAFC setting you set and get back to it's set parameters. Traditionally Honda errs on the rich side of fuel trim. Look at any honda and you'll see tons of soot in the trail pipe.

You can always reset the ECU when you want to revert back to the original VAFC setting...easy way is to install a switch to remove backup power to the ECU.

To fix the root cause you need to reset the parameters for fuel trim calculations using by resetting the fuel tables. i.e . Hondata, Crome, Uberdata, Power FC etc. VAFC will not do this.

Hope this helps.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by DC2_005200 &raquo;</TD></TR><TR><TD CLASS="quote">I had my VAFC II in my 94 GSR, also some of the guys have the VAFC in an 95, 96 and 97 GSR, and my final thought on them is just to get a Hondata system. I mean its great and everything. I love it, but my problem was that when I ran in against a stock ECU it will throw out a check engine for a VTEC problem, so I had it in, but always had to leave it on defult. Now the guy with 95 GSR had to dyno his car and come to find out that he need to rip out his. I means to get the max out of your VFAC you have to dyno it, but when you get to the dyno, mostly everyone recommands Hondata. Plus most of the time Hondata is cheaper and less open. If you leave your VAFC out near your shifter or near your radio, people then to break into your car thinking you have crap to steal. YES THIS HAPPEN TO ME!!!</TD></TR></TABLE>

i agree, hondata

 

STFT and LTFT are not non-standard acronyms. Unfamiliar to some people, but definitely not non-standard.

Now this is non-standard. I would have preferred re-calibrate.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">reset the parameters for fuel trim calculations using by resetting the fuel tables</TD></TR></TABLE>

If you get the partial throttle STFT and LTFT close to zero corrrection, it'll minimize or eliminate the effects of the LTFT on WOT conditions. That way you won't have to reset the ECU all the time.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by IN VTEC &raquo;</TD></TR><TR><TD CLASS="quote">STFT and LTFT are not non-standard acronyms. Unfamiliar to some people, but definitely not non-standard.

Now this is non-standard. I would have preferred re-calibrate.


If you get the partial throttle STFT and LTFT close to zero corrrection, it'll minimize or eliminate the effects of the LTFT on WOT conditions. That way you won't have to reset the ECU all the time.</TD></TR></TABLE>

Yes standard industry terms but non-standard on this message board.

Sorry for the typo... yes you're right; "re-calibrate."

To the original poster: Even without your mods your car ran rich from the factory. Adding a VAFC and tuning it to be more lean will help you but the stock ECU will eventually go back to where it's programmed to be.

 

still dont understand why you would throw a CEL in a obd2a car w/ the vafc2?
someone care to enlighten

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by DC2_005200 &raquo;</TD></TR><TR><TD CLASS="quote">I had my VAFC II in my 94 GSR, also some of the guys have the VAFC in an 95, 96 and 97 GSR, and my final thought on them is just to get a Hondata system. I mean its great and everything. I love it, but my problem was that when I ran in against a stock ECU it will throw out a check engine for a VTEC problem, so I had it in, but always had to leave it on defult. Now the guy with 95 GSR had to dyno his car and come to find out that he need to rip out his. I means to get the max out of your VFAC you have to dyno it, but when you get to the dyno, mostly everyone recommands Hondata. Plus most of the time Hondata is cheaper and less open. If you leave your VAFC out near your shifter or near your radio, people then to break into your car thinking you have crap to steal. YES THIS HAPPEN TO ME!!!</TD></TR></TABLE>

agreed to. i bought my turboed gsr and the owner said to get a hondata. last nite my AFC got ****** stolen so imm really pissed off. hopefly theyll pay sum of it and ill be able to get a hondata system.

 

the car keeps throwing a code 71 itll go away then come on agian a week or two later.