So I just needed some clarification is SAFC is only really affective during WOT? because during normal driving the stock ECU will compensate for any adjustments? what gains have people seen with SAFC tuning on a stock GE all the forums i've search show the sc400? any feedback is great
thanks in advance guys

 

No, the SAFC has HI/LO settings that can be altered by throttle %. Airflow can be adjusted everywhere at the specified breakpoints, but not under multiple load settings, or 3 dimensionally.

 

The ECU will try and relearn its own settings - so most people have to pull their power to the car every couple of weeks to reset the factory ECU.

Jonny

 

From what I've read, the ECU will relearn the part throttle stuff so it's pointless to change it as it will eventually start to affect your WOT as well.

By suggestion I left my low settings alone and only adjust when the car is at 95% throttle and above when the ECU isn't adjusting anything and my AFR's haven't changed since I set it up.

 

I had my low throttle at 30% and high throttle at 85% on the s-afc. tuning was a breeze

I do, however, prefer pressure based (MAP ECU or similar), instead of a s-afc like tuning device.

Allen

 

So when setting the HI/LO if I set the low to 30% is SAFC gonna only adjust at 30% or does is it like go from 30+% to a certain point and when is that point? sorry for all the questions. Im picking one up this weekend and looking into a AEM wideband also, was wondering if I can get some information on how to tune with the wideband and what should A/F be at with just an air intake
thanks for the help fellas

 

the way the afc adjusts is based on the throttle percentage. so say if ur set at 30% low throttle, then it will try to adjust to the low throttle settings at 30% throttle, and same for high throttle. any area between the low and high throttle will be the average settings of the high and low throttle at that rpm.

for an NA application, i'm pretty sure an a/f ratio of around 13:1 would be ideal, close to stoichmetric yet lil bit more fuel to cool the combustion chamber.

for a turbo application, i think ideal is around 11.5-12:1 depending on tune.

 

Hmmm I thought that it was better to run lean? but not too lean that it causes detonation. can anyone give me steps on how to street tune with wideband, i.e. what gear I should be in and such
thanks guys been alot of help so far

 

well i have the a'pexi afc neo, and i street tuned it till i have sometime to go to a dyno..and i have an air and fuel gauge.so when ever am lacking fuel i jus add where it is needed...and it feel like i gained some hp

 

that NA target AFR seems a bit high
there is a book great for learning about this stuff called How to Modify and Tune using and Engine Management System
great book.

Also, 11.5 is a great AFR to run for TURBO, but it's also risky, w/ an s-afc u better be really good at tuning and now how to move the NE points, or else u will get fluctuation, and in which case just aim for a MAX value, and the street guys usually aim for solid 11.
remember the video that a member has on here, the black drag 2jz running a 10.1 but sitting at like 7k for 8seconds solid

for daily driving, if you want to tune w/ the s-afc and a wideband, you MUST disconnect the O2 sensor that is feedbacking the ecu. Then this is where i had to punt since i am rusty, but i'd aim for 12.5-13.5 depending on RPM.
when all done, plug in the stock O2.

it takes time to get a good tune using anything, i am lazy and just did every like 800rpms and have mine fluctuate from 10.1 to 11.2.
the area where spool occurs(if changed from stock) is going to be the biggest pain along w/ possibly 4k-5k where stock ecu's tend to go rich

*EDIT* RICH IS BETTER THAN LEAN. The ADDED FUEL WILL COOL THE CYLINDERS. hence the 10.1 compared to 12.5 which iirc is the DREAM combination(the book covers best tq and best hp, but in order to cool, more fuel)

 

after reading some of the other forums Im finding it difficult to decide If I should just take it to get tuned on a dyno or buying the wideband and tuning myself, but the question is because the air temperature here fluxuates so intensely through the seasons 30C to -30C. will I have to retune on the dyno to compensate for the extreme change in air density? so with that thought should I just stick with getting a wideband?

 

I've tuned mine myself with an AEM wideband.

 

11.5 with an SAFC is NOT risky. I dynotune (for a living) cars all day long and have been doing it for years, and with that target A/F, and I've never had a problem. Evo's, DSM's, Supras, Skylines, etc. All were fine. When tuning with an SAFC the major things you need to be aware of is that pulling airflow out will advance the timing, and that there is NO boost comp, meaning once the car is tuned at a target A/F, if you run less boost than that, it'll run lean. This is why, when tuning with an SAFC, you keep extra fuel in up top, but 11.5 on a turbo car isn't wrong with an SAFC or anything else for that matter.
On an N/A car, 12.5 is too rich to make any power. I run 13.5-14.0 on Hondas/other N/A cars, and if you go check other advanced discussions, on N/A tuning, you'll see that while that number may vary depending on the car, it's almost always in that area, but normally no less than 13.0 for N/A. All you have to do is work in baby steps and watch peak tq, and see if you're making gains in the powerband. If you are, you move along, if not, you stay where it is. There will be a point where you'll gain more hp, but not tq, when you hit that wall, that's when you know there's no more to be had with A/F tuning. Also, I've never had to disconnect the O2 sensor when tuning a 2J, RB, or anything else. I've never had a problem with LTFT/STFT. As far as spool is concerned. You can run the car from 13.0 down to the target A/F because there won't be cylinder pressure just yet. As boost is rising, you add fuel in so it's a nice slope down to your target A/F. That's the proper way to do it. Again, I've used SAFC's to make 750whp and never had a single problem. You just gotta have some clue of what you're doing. His best bet is to take it to someone who knows how to tune, because if he's trying to learn to do this reading on the forums, he's gonna end up in trouble.

 

yeah i was thinking it would save me a lot of headache if I just got it tuned by someone on a dyno... do you know If the changes in air temperature are gonna affect the settings. so will that mean I will hafta get it tune for summer and winter seasons

 

you don't have to disconnect the stock o2 sensor to run a wideband and tune. i have mines setup so that it runs as dual function. i have a wire from the controller running to the ecu to act as a narrowband while another set of wires run to the included gauge to act as a wideband. i have my wideband placed in the header o2 location to keep it ahead of the cat. i will note that when i took it to a dyno to tune, compared to their o2 in the tailpipe vs my wideband, their o2 sensor read 1 point leaner than mines.