You dont want to tune it by yourself. You need to take it to a reputable tuner.
Every car is different so you cant just use somone elses settings.

The install is self explanitory as per the manual. Solder the wires.

The only thing that may be tricky is for the 04 owners, because the ECU pinout is different.

 

You dont want to tune it by yourself. You need to take it to a reputable tuner.
Every car is different so you cant just use somone elses settings.

The install is self explanitory as per the manual. Solder the wires.

The only thing that may be tricky is for the 04 owners, because the ECU pinout is different.

I am also going to be installing a wideband O2 sensor, so I will be tuning it myself, if no wideband then I would definately bring it somewhere to have it dyno tuned. I also would NEVER use anyone elses settings, each car and location is different (fuel maps, elevation, climate, etc), I am just curious how the whole "correction percentage hi vs low throttle and throttle percentages" thing works.

 

do not use the low throttle settings they will only fight with the short term fuel maps.

 

I am assuming there is a way to "turn off" and not use the low throttle settings?

 

high throttle: :
3200 - +5%
3600 - +14%
4000 - +13%
4400 - +11%
4600 - +9%
4800 - +5%
5200 - +0%
5600 - (-3%)
5800 - (-3%)
6200 - (-2%)

all i can give are my settings, sorry.
there are two "runfiles" with the s-afc2, allowing you to run stock fuel maps or modded ones with the switch of a button.

the guy who did my tuning also did the low throttle, and on the highway i get an SES light for the MAF... so be warned!

 

Contrim....what do you mean by not using the low throttle settings? 0 all of them out?
What about on a turbo car like mine?

 

high throttle: :
3200 - +5%
3600 - +14%
4000 - +13%
4400 - +11%
4600 - +9%
4800 - +5%
5200 - +0%
5600 - (-3%)
5800 - (-3%)
6200 - (-2%)

all i can give are my settings, sorry.
there are two "runfiles" with the s-afc2, allowing you to run stock fuel maps or modded ones with the switch of a button.

the guy who did my tuning also did the low throttle, and on the highway i get an SES light for the MAF... so be warned!

Ok, so the +'s mean your making it leaner or richer (adding air or fuel)? From what I've read, our cars run rich low and mid and run leaner up top.

Wouldn't one want to set the low throttle to get the AFR to stoich for gas milage?

Also, just what he asked, set all corrections to 0 to negate the low throttle settings?

 

high throttle: :
3200 - +5%
3600 - +14%
4000 - +13%
4400 - +11%
4600 - +9%
4800 - +5%
5200 - +0%
5600 - (-3%)
5800 - (-3%)
6200 - (-2%)

all i can give are my settings, sorry.
there are two "runfiles" with the s-afc2, allowing you to run stock fuel maps or modded ones with the switch of a button.

the guy who did my tuning also did the low throttle, and on the highway i get an SES light for the MAF... so be warned!

The guy who did your tuning is an idiot.

a) why the hell is that much fuel being added in the low rpms when at WOT? Not necessary. And you're hardly having any fuel taken out in the high rpms where you WANT to take out a bit of fuel (on an N/A qr25de). Ex: I am running as high as -14% at one rpm point in the upper rpms at WOT. My a/f is ~13:1-13.5:1 from 4k-6krpms.

b) You DO NOT need to do anything with the low throttle settings! On the 02-03 qr25s the ECU bases the fuel maps off of our 2 o2 sensors at low throttle. The aim here is for fuel efficiency. The ECU WANTS to be at stoichometric when at cruising speeds so we get the best gas mileage possible. If you mess with the low throttle settings you will only end up pissing off the ECU and it will fight/negate the changes the safc-II is trying to make. Hence why you're probably getting the SES lights for the MAF when cruising on the highway. Now when we go WOT or above ~50% throttle the ECU bases the fuel maps off of both the o2 sensor readings AND the MAF primarily.

Point is:

On the 02-03 qr25 ECUs leave the lo throttle (below ~10-20% throttle) settings at zero.

High throttle settings (above ~50%) is where you'll do your tuning.

 

Ok, so the +'s mean your making it leaner or richer (adding air or fuel)? From what I've read, our cars run rich low and mid and run leaner up top.

Wouldn't one want to set the low throttle to get the AFR to stoich for gas milage?

Also, just what he asked, set all corrections to 0 to negate the low throttle settings?

1) - means the safc-II is telling the ECU that the MAF voltage is less so the ECU then adjusts the fuel tables to accomodate 'less' air flow coming into the engine. This way you still in reality have 'x' amount of air coming into the engine, but the ECU thinks differently. Say you have 200cfm of air entering the engine, the MAF will register this via a certain voltage output to the ECU, BUT with the safc-II the ECU will get a different voltage reading. So you'll still have 200cfm of air entering the engine, but the ECU only thinks 180cfm is coming in because the safc-II is manipulating the MAF voltage (hence why the MAF wire is the only wire we cut and not just splice into.) So in reality the +/- = more voltage or less voltage signal being sent to the ECU. I hope that made sense.

2) As I said in my last post on the 02-03 ECUs the a/f is ideally maintained at stoichometric by our o2 sensors (at low throttle) then when we go to WOT the ECU shifts the fuel maps and bases the reading primarily off of the MAF sensor.

3) Yes, set the low throttle settings to zero and you'll be all good.

 

The guy who did your tuning is an idiot.

after thinking about it for a bit, i think your right. im gonna turn off the low settings so my damn ses light won't go off.

i called him today to get some answers.... i'll get back to you guys.

 

Cortrim1....what do you mean by not using the low throttle settings? 0 all of them out?
What about on a turbo car like mine?

you have a turbo car its different. You are using larger injectors and have to compensate for them. I am also sure you throttle switch over point is pretty low so you don't go lean under boost.

 

So, according to our ECM, more voltage means more air (ECM adds more fuel), less voltage = less air (ECM leans it out).

According to this image (courtesy of Avatargsr from his '03 Spec V), the general trend is for the motor to richen up as revs increase, which would make sense with the corrections that SpecVracer is using. HOWEVER, Avatargsr has an SAFC listen in his sig (not sure if he would have had it installed at this time and the corrections are allready apparent on the graph)... This is the only AFR graph I could find, if someone has a stock one lying around I'd love to see it.

 

Here is my last dyno (prior to installing GWs, DP, and TA)

I know it's a little hard to see, but this dyno compares my baseline dyno w/ only a CAI to then I/H/E/P/BSR/safc-II/KS/TBBP

Look at the a/fs below the graph:

Red = stock fuel maps = pig rich in the upper rpms (hovers ~11:1)

Blue = after safc-II tuning = better 13.1-13.5:1 a/f ratio

Off the top of my head my settings are (low throttle 10% high 50%)

Low throttle settings all set at zero

High throttle settings:

2200 -2
2600 -3
3000 -2
3400 0
3800 -5
4200 -6
4600 -8
5000 -10
5200 -12
5600 -14
6000 -11
6200 -11

These are from what I can remember, I'll have to check later to give you exact numbers, but these are close. I've been running these for over a year now and my Spec runs strong as can be. My best at the track so far has been a 14.6@95.8 (best trap one time was a 96.4) but I was on the stock Contis and was having major traction issues so my 60' sucked. This car is capable of low 14s with the right tires and the nut behind the wheel properly calibrated.

 

Fantastic, thanks for the dyno... I'm stuck at work (paint won't cut it), can anyone lighten that up for us?

 

my chart can be seen on page 2 of my cardomain page. the link is in my sig

 

Red X

 

I drew a line at 13.5 for reference. Thanks again.