So I finally got around to tuning my wideband on the street and started logging and changing values in my VAFC.

I was doing 3rd and 4th gear pulls, and I had to pull an ASSLOAD of fuel out on the top end! Like above 6k, my VAFC settings are about -18 across.

The thing is, I am running an H23 VTEC and figured I would be using a considerable larger amount of fuel on the top end than on the stock H22........so does this sound right? It runs fine after tuning.

 

crate pulled about 24 out of his top end when tuned with a wideband, so i can easily believe it

 

Alrighty then, thanks.

I was worried about that. I knew we ran rich from the factory, but not THAT rich!

 

got a quick question.....

i got a vafc 2 and I have a pos autometer a/f gauge

But i knwo that when im in vtec my car runs rich as well...

can i bring the settings down at like (5000K rpms) to like -2 or 3 or whatever? and see if its faster? NOTHING crazy

 

i have about -18 up top with cams and pistons etc. kinda made me wonder at first too but i know i calibrated the wideband right. doesnt detonate and the plugs look good. although i will say im quite concerned about the timing when that much fuel is taken away

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by LudeyKrus &raquo;</TD></TR><TR><TD CLASS="quote">So I finally got around to tuning my wideband on the street and started logging and changing values in my VAFC.

I was doing 3rd and 4th gear pulls, and I had to pull an ASSLOAD of fuel out on the top end! Like above 6k, my VAFC settings are about -18 across.

The thing is, I am running an H23 VTEC and figured I would be using a considerable larger amount of fuel on the top end than on the stock H22........so does this sound right? It runs fine after tuning.</TD></TR></TABLE>

u get that thing reading right? not 17:1 anymore? fix your exhaust leak before tuning? i might go to boost solutions this weekend, maybe u can come and compare o2 readings? if not, want to let me use yours and ill compare the readings to the dyno

im bout to go fix my stupid hose and give the lude hell

call me i lost your #

 

you guys should becareful when pulling too much fuel with a vafc, your gonna severly **** up the igintion curve. Don't force the engine to run leaner. If it doesn't lean out after pulling 10-15% then dont bother.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by fastludeh22 &raquo;</TD></TR><TR><TD CLASS="quote">

u get that thing reading right? not 17:1 anymore? fix your exhaust leak before tuning? i might go to boost solutions this weekend, maybe u can come and compare o2 readings? if not, want to let me use yours and ill compare the readings to the dyno

im bout to go fix my stupid hose and give the lude hell

call me i lost your #</TD></TR></TABLE>

Called ya.

yeah, I got it running right. It turns out that the code #41, the O2 sensor heater code, was making it run off of some stupid map......I think it was bypassing the O2 sensor. And I got that busted exhaust gasket taken care of

Call me if you end up heading to the shop today, I'll take a break and head down there w/ ya.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by LudeyKrus &raquo;</TD></TR><TR><TD CLASS="quote">So I finally got around to tuning my wideband on the street and started logging and changing values in my VAFC. </TD></TR></TABLE>

Stupid question here but how does one tune their VAFC on the street? I know you need a wideband sensor ofcourse and some type of logger, but what type of logger are you using? and what are you looking at specifically so you know to pull fuel? I know 14.7 dead on isnt allways the best fuel ratio for power, so how do you measure the power with a logger?

 

The wideband comes with a cable and software to hook up the logging box to your laptop. You use the software to log what the wideband says when you make a pull in a gear. You then look at that log, and see where it runs rich or lean. You then look at what RPM it was running rich or lean at, then make a change in the VAFC at that RPM. Then you log a run again, and see how the change in the VAFC affected the fuel curve, and make more changes if necessary.

If you have a wideband and a VAFC (or anything else to tune with), then you can tune your own car.

Oh, and typically you try to keep the a/f at 13.5 on an n/a car, not 14.7

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by LudeyKrus &raquo;</TD></TR><TR><TD CLASS="quote">The wideband comes with a cable and software to hook up the logging box to your laptop. You use the software to log what the wideband says when you make a pull in a gear. You then look at that log, and see where it runs rich or lean. You then look at what RPM it was running rich or lean at, then make a change in the VAFC at that RPM. Then you log a run again, and see how the change in the VAFC affected the fuel curve, and make more changes if necessary.

If you have a wideband and a VAFC (or anything else to tune with), then you can tune your own car.

Oh, and typically you try to keep the a/f at 13.5 on an n/a car, not 14.7</TD></TR></TABLE>

Ahh I see so your just going for optimal a/f and hope it makes more power, which it should...but using the dyno would be better. Thanks.

 

Well all a dyno does is load down your car like it was on the road....but it's not moving. This just makes it easier to tune in the building. It also measures horsepower............so street tuning will still make the same power if you tune the same way, it's just you won't know exactly how much you made before and after.