I am hoping to get some feedback from those that have been through this and can help interpret what the AFR's mean during the rpm and boost cycles.

I thought I had AFR's after my first data log but it was only a 1st gear pull near my neighbor hood. After I got the Zeitronix wide band working again I decided to log on the way home today. I was able to get a couple of good runs in. A rolling start, a 0-80 mph and a 40-90 mph.

Max psi – 19.7
Lowest AFR – 9.6
Highest RPM (auto mode) – 6100

AFR’s are frighteningly low, even after let off when thereis no throttle or boost (actually opposite, there’s 23mmHg) the RPM’s are stillup but the AFR stays way too low for a while. The AFR’s don’t stay consistent they will go up to 10.5 or 11 on somepulls but stay down in the 9’s on others.
Mods - DCAI, 62mm SC pulley, boxed Euro charged tune, using 93octane and it was 85 degrees outside.

Is there a need to calculate duty cycle to keep the AFRup? Is it time for injectors, SL55 fuelpump, and looped fuel rail? Or just geta looped fuel rail with fuel sensor for the wideband and check fuel pressurewith wideband and datalogs before the pump?


Here is the rolling start

a3594f79-2873-44ee-80d1-87f11280fe1d_zps15366333.jpg


here is the 0-80 from 1st gear to 2nd

0-80pull1stadn2ndgear_zps412e92e5.jpg

here is the 40-90 from 3rd to 4th

50-90pull3rdto4th_zps385ea999.jpg

 

I have AEM wideband and I am reading very lean. I am going to change my sensor. I have been told the sensors go out on them frequently. WOT I am reading 15-16. Cruising I am reading 14.7 perfect. If you find out information please let me know. I was also thinking about changing fuel pump & injections

 

You guys do realize that

<11 = rich

>12 = lean... right?

Jesse -- 9.6 AFR is a bit fat, you can lean that out and recoup some horsepower. If you're at ~10.9 under WOT at max boost, that's about where you want to be based on my memory from Anthony's best tunes.

Austin -- AFR's in the 16's are DANGEROUSLY lean... like, meltdown area. Don't do another WOT pull until you get your tune sorted out.

 

Yes totally understand. Typo. I have been told that. Super dangerous. The engine is running super strong. I'm thinking its the sensor. The gauge is old. I have not seen it in the green. Its stays at 14.8. All the time even in WOT. I took the car to dealership they hooked it up to the computer and told me my o2 sensor were good. I totally confused about it. If you have experienced an AEM gauge I would appreciate the help.

 

Once a car has been tuned does it need to be tuned again.

 

I'm in the mid 12's mostly. My first tune was on a dyno and the target, which we hit, was 11.8. It's leaner now after more mods. Under 11 and I'd retune. Over 12.5 I'd retune. I'm on the borderline but I run 100 octane at the track. Well, realistically, about a 50/50 mix of 93 and 100.

Les

 

Once a car has been tuned does it need to be tuned again. How can tell if a car is out of tune. The mechanic hooked the car to computer turned the key and said the sensor was good. I live in Louisville Ky no one knows anything about these cars.

 

New pump and new injectors...problem solved. Call rob at needswings, we get our pump and injectors from him.

 

Jesse, first make sure your wideband is reading around 14.7 AFR while cruising (closed loop). Just to rule out a sensor issue. I couldn't tell from the logs.

 

Do you know who the original tuner is?

 

Jesse, You have more than enough pump and injector for your setup. As stated above, it should be leaned out just a tad(less fuel).

 

I'm really shocked he's running as fat as he is, since he's running a bone-stock fuel system.

I thought surely I'd be playing with fire if I DIDN'T upgrade to at least bigger injectors... in retrospect, that might be why I ran so damn slow at the 1/2 mile

 

My stock system is healthy also....pulled a little fuel to get the afr's good.

 

The first place I'd look with a lean AFR and an E/C tune is the fuel filter. Larger injectors .... too much trouble for me. Much easier to upgrade the pump, which I have.

Les

 

First thing I would do would be check and make sure the wideband is giving me the right reading.

 

Reading this, I seriously need to put my stock injectors back in and sort out the other problems...

 

I was told by previous owner inmotion

 

tunaglove how can you check the reading is right.

 

[QUOTE=JHM2K;758826]You guys do realize that

<11 = rich

>12 = lean... right?

Jesse -- 9.6 AFR is a bit fat, you can lean that out and recoup some horsepower. If you're at ~10.9 under WOT at max boost, that's about where you want to be based on my memory from Anthony's best tunes.QUOTE]

Wow, I really messed this one up. You're right. So I am not lean according to the graphs, it is rich. Not a dangerous problem, just not ideal, right? Sooooo, I have room for more boost!



Tunaglove, thanks for pointing out that I need a baseline and to see if things are calibrated. I opend all the files back up and am consistently showing 14.7 AFR for normal crusing, ie. 15-20% TPS and around 2,000- 2,500 RPM.


I would like to get a reading on the IAT's, what is the best way to tie this into the wideband?

 

[QUOTE=JesseJamessrt6;758930]using the dashdaq you can log iat thru it.
crap tune
no need to replace the inj. just need a decent tune. i ran 550 cc inj. stacked pulleys, sl55 fuel pump and 11.9 afr at wot. it was all in the tune running 5% lt/ft
cars dont fall out of tune unless you change your mods. tunes are updated due to weather conditions or power adders. if you tune for conditions and dont change anything the tune lasts forever
14.7 to 15 afr during a cruise is normal for closed loop driving. open loop ie: wot needs to be 11.8 to 12.2 . if the gauge is bad why trust it?