gspot35

I just installed a AEM wideband the other day. What do you guys read on your gauges at idle and full throttle. At idle mine bounces back and forth from 14.2ish to 15.1 ish. I know 14.7 is perfect for idle, but I expected the gauge to be more stable. This thing is all over the place. At full throttle it shoots sub 11:1 and it's off the charts.

I'm going to the track on Thursday and wanted to do some tuning, should I try dropping the fuel until I atleast see it in the 11:1 range throught the revs? Timing map should not be touched to maintain safety, true? Is it reliable enough to even tune with?

HELP!

booger

iTrader: (6)

If your wide ban o2 sensor is before the cat it will jump all over...mine did to....I now have it after the cat and it doesnt jump around as much....and at idle it sits pretty much on 14.9 and goes back and forth from 14.7 to 15.1 when it does move

GurgenPB

iTrader: (2)

the whole point of this isto have hte wideband sensor sit BEFORE the cat, so that you can get an accurate account of the reading.

Mine is pre-cat and it fluctuates b/w 14.6 and 15.2.

gspot35

What about at full throttle during boost, does yours bury below 11:1..do you think I should pull out some fuel until I see it near 11:1 or 11.5:1?

etx

It's normal for the readings to bounce like that. That's the ECU adjusting the fuel trims via the nbO2.

You have your wb after the cat? LOL! That's virtually useless.

My wb reads about 11.8:1 under boost, it dips down to about 11.2:1 near redline.

gspot35

Thanks ETX, I have mine before the crawford cat, right near the flange. Should I attempt to remove fuel until I see my a:f in the range of low 11's?

booger

iTrader: (6)

I see you think thats funny ...lol....well if you had talk to any good tuner....with 25 or 30 years at it....they should tell you...At WOT the high flow cat does little of anything to the gasses going thru it , and the readings from one side of the cat to the other would be only minimal . The Crawfords leave little room to put a bung before the cat

Sharif@Forged

iTrader: (92)

I would also never put a wideband after a cat. Even if the reading is only slighly altered...why would you do it? I want the cleanest most accurate air sample possible...and before the cat is the source for that.

The reason the wideband bounces a bit is because it is spot-on deadly accurate, and it will fluctuate radically at idle and cruise. At WOT, it tends to be a bit more stable. If you are dropping to sub 11:1 across the board, I'd try to lean it up. But sometimes, mine looks like it goes sub 11 when I first go WOT, and then quicly stabalizes at about 11.5:1. So just do some practice runs to make sure it's not just one spot of richness.

Good luck!

gspot35

Thank you for the answer GQ...I'm going to check it out tonight on the track, I'll post results for the curious.

booger

iTrader: (6)

I didnt want to put it after the cat either...but Like I said...no room... We have the O2 to make sure the A/F doesnt get out of wack . And with little or no difference in the readings...whats the difference.....If you feel your better off with it before the cat...good for you

esemes

boog-

for 30$, doug welded an extra O² bung upstream of the cats (that i bought from him)....

maybe he can do the same for you, and then you can plug/weld the existing third one??

just a thought
'
es

booger

iTrader: (6)

Ive already had one put one after the cat...and Im not going to take it off to do it again for a .02 better reading

gspot35

Well after an event full evening at the track, I ran a 13.54 @ 103 mph, with my a:f shooting sub 11 at about 3500 rpm. After totally screwing up the R4 mapping and basically learning my way through it, I was able to get the old map loaded and modified it to -.08% on the cells between 1psi and 3500 rpm and 9psi and 6500 and the track closed. On the way home though it was hitting sub 11 right at about 5500 rpm.

Is this the best way to adjust a slightly rich mixture. Just highlight a big block and adjust slightly -1% until it gets to the right place?

etx

I shoot for about 12.8 @ 2psi and 11.8 by 5 psi. Running a little lean at low boost will help the turbos spool up.

Of course this only applys at WOT when the car is in closed loop.

gspot35

I'm running a vortech supercharger, but the case remains, I still want the car to run as n/a until about 2.5-3 psi then start pumping in the gas to get it near 11.5-11.8 correct?

zimbo

iTrader: (4)

My own goal with the Vortech was to have about an A/F of 12.5 at 3500 rpms and slope downward to 11.4 at redline. Under wide open throttle, of course.

--Steve