S-AFC Tuning

GEN1GST · 11-27-2004, 08:18 PM

i have a 92 gst, i have these mods..
3" HKS Upper ICP
HKS SUperMegaFlow intake
3" intake piping to turbo
GReddy lower ICP 2 1/2"
GReddy FMIC
N1 catback
boostcontroller
02 housing ported with external waste gate dump
hacked maf 9honeycombs out and screw flush)

i have a sparatic and rough idle and just want a general outline of what my thr% and dec-air should be set at as well as the other settings. can someone help????

evil_eagle · 12-02-2004, 02:55 PM

here are some good baseline settings to use, but 1st what injectors are you running, what pump?? I need to know these things to help you on the fuel maps.

throttle points
LOW 20%
HIGH 75%

TPS Arrow pointing up to the right
airflow sensor Karmen vortex

decel and all that bs don't worry about that as it does not do anything.

AS far as your idle, just richen it up or lean it out to find where the car likes it.

Now for the fule settings.

Stock fuel system, no more then -5 across the board, your car may need more fuel, hard telling. But you have your MAF hacked (lower honey comb removed and your screw out flush) you will need to richen things up at 1000rpm to get your idle back.
You need some type of wideband, or somthing to tune with, IE datalogger, wideband, EGT gauge, blah blah blah.

Let me know what your fuel system is like then I will be able to help you more.

-Jake

GEN1GST · 12-03-2004, 12:35 PM

im running stock injectors and fuel pump.

GEN1GST · 12-03-2004, 12:38 PM

i plan to get a logger in the next couple of weeks. so i know that will help out with tuning i just wanted to see what i could do now!!
thanks,
jeremy

CanadianTSi · 12-03-2004, 01:05 PM

Quote:

Originally Posted by GEN1GST

im running stock injectors and fuel pump.

Leave your settings at 0 and don't bother with dec-air

GEN1GST · 12-03-2004, 01:22 PM

all settings??? i should just wait until i get my logger b4 tuning???

GEN1GST · 12-03-2004, 01:23 PM

my idle... when i first start the car up it seems to want to die and then after it warms up it runs and idles better.. any ideas?

CanadianTSi · 12-03-2004, 02:37 PM

Quote:

Originally Posted by GEN1GST

all settings??? i should just wait until i get my logger b4 tuning???

You can't really do much tunning with a stock fuel system...

evil_eagle · 12-03-2004, 02:50 PM

You can tune a stock fuel system, I have thrown widebands on bone stock fuel systems on DSM's 1g and 2g and from the factory they are pig rich, on one of the cars I put the wideband on it was at 10.8 A/F ratio, that was on a 1g, the other was a 2g and the A/F ratio was at 10.6 :eek: That is at bone stock boost levels as well. You can get away with around -5 % on the afc, that is if you are running stock boost levels and stock turbo.

But on your car GEN1GST I would stick with 0% like stated above since you have a hacked maf. But every car is different, but I do know that dsm's come out of the factory pig ass rich.

just my 2 cents.

-Jake

GEN1GST · 12-04-2004, 06:07 PM

so basically if i up my injectors and fuel pump i would have more tuning capabilities with my afc??? what is your take in a gm maf translator with a gm maf???

GEN1GST · 12-04-2004, 06:08 PM

so basically if i up my injectors and fuel pump i would have more tuning capabilities with my afc??? what is your take in a gm maf translator with a gm maf???

97TSIAWD · 12-05-2004, 12:43 AM

Subsequent question for this guys. I am not near my car or manuals but is it possible to tune the fuel using .5% instead of a full 1%? I would think that you would be able to for more fine tuning?

GEN1GST · 12-05-2004, 10:22 AM

just make the adjustments using smaller increments??

Coup D E'Tat · 12-05-2004, 10:38 AM

Quote:

Originally Posted by GEN1GST

so basically if i up my injectors and fuel pump i would have more tuning capabilities with my afc??? what is your take in a gm maf translator with a gm maf???

If you already have an AFC, there's no reason to buy the MAFT.

97TSIAWD · 12-05-2004, 12:32 PM

Quote:

Originally Posted by GEN1GST

just make the adjustments using smaller increments??

That's my question can I change my settings so that I tune by only .5% and not a full 1%? Maybe in the settings part of the safc, for the past two years I've only been using 1% but I think now I have to more finely tune it.

WhiteTsiAwd · 12-06-2004, 07:49 AM

Quote:

Originally Posted by 97TSIAWD

That's my question can I change my settings so that I tune by only .5% and not a full 1%?

No you can not use .5%, only .1%.

97TSIAWD · 12-06-2004, 01:33 PM

Quote:

Originally Posted by WhiteTsiAwd

No you can not use .5%, only .1%.

Damn, thanks for the reply.

dsmstud04 · 12-09-2004, 09:01 AM

What about a fuel pressure reugulator? I dont know if that was mentioned, probly implied at least

GEN1GST · 12-09-2004, 10:27 AM

Quote:

Originally Posted by Coup D E'Tat

If you already have an AFC, there's no reason to buy the MAFT.

wouldnt it be easier with a gm maf and a translator?? i know they have the setting already in the translator.

eclipse90gsxt · 12-09-2004, 11:17 AM

You don't need a adjustable fuel pressure regulator for a stock fuel system. You can with the 1000/2000 points, or if you changed them, add/give fuel depending on how your car idles. You said it wants to die, so try adding a few %, and if that makes it die, then take away a few % until its "normal." The Gm maf has the translator but you still must set the base line settings and tune but hand. You have to log a run, go adjust the switchs in the box, log some more, adjust etc.. Just like the afc, but not in a graphical interface. A logger will help greatly and I wouldn't touch any other fuel levels until you know what the car is actually doing.

Coup D E'Tat · 12-09-2004, 01:33 PM

Quote:

Originally Posted by GEN1GST

wouldnt it be easier with a gm maf and a translator?? i know they have the setting already in the translator.

They have base settings, doesn't mean it's any "easier." I guess it's all preference. There have been lots of threads "AFC vs. MAFT," and both have there ups and downs.