just got my 550's in.... now for some tuning help on the S-AFC

[mitsugsx95]

I just installed my 550's today and would like some input on what to put the settings at. I am following the tuning path of this at the time.

http://home.attbi.com/~tarryo/kyle/tuning.html

I am going to start off with -10 for Low, and the same for High. I do not want to tune for maximum power at the time, just want to have a safe driving setting. Also, when datalogging, should I be looking at STFT or LTFT, or both? I know that the 2gs are suppose to be at 0%. And is it suppose to fluctuate when you are driving ( when accl. and decel.)
Thanks.

small list of mods:
sm16g
190lph
550's (new )
S-AFC
supra SMIC
IC pipes
full 3' turbo back exhaust
hks BOV
gauges (duh)
intake

 

[kpt4321]

While sitting at idle, tune the low throttle map at the 1000 rpm point. Tune it until the sum of the two fuel trims is 0%.

Then, while driving, tune up through about 4k rpm, on the low map.

Then, you can go over to the hi map.

I feel like this is redundant, since that is all in the tuning guide....

.....Kyle T.
93 TSi AWD "TURBO4"
14b - 12.8 @ 108

 

[mitsugsx95]

Ok, I tried tuning the low. I have it at -5. should I be leaning it out or richening it up at the low throttle? It says on the datalogger that 1k should be around -2, but for 2k and 3k, its alright at -6. Is it ok to keep it rich at low throttle.

 

[mitsugsx95]

I did a run last night with the highs at about -6. (@15psi)
RPM timing o2
3420 31 .86
3696 8 .98
4232 11 .98
4756 11 .98
5264 13 .98
5772 16 .98
6220 19 .98

Are you trying to tune for timing advance? Should timing be pulled at higher RPMs of more of it?

 

[Blk_99gst]

Originally posted by mitsugsx95

Are you trying to tune for timing advance? Should timing be pulled at higher RPMs of more of it?

Yes you mostly tune by timing advance. When boost hit, timing should dip down to 9 or so, then it should stay the same or always increase throughout the rest of the gear; ending up near 18-20degs at the top of the gear. If there are any dips when timing goes down, that could be a good indication of knock at that rpm level.

Even though you can not tune off of 02 voltages, .98 would say you were pretty rich.

 

[nowayout]

it you r running rich your timing will go up at higher RPM.

19 is no big deal. i try to keep my timing at 20 or above all the way to red line.

 

[mitsugsx95]

Im going to try and lean it out a little and go for aonther pull later tonight. Ill post up some numbers.

 

[kpt4321]

We can't tell you if you should be richening or leaning it out at low throttle, that's what the loger is for.

If the logger still has negative fuel trims, then keep leaning it out on the SAFC until the fuel trims are about 0%, all the way across.

I too think you should lean it out a bit more. As you do this, you will probably see timing increase at first, then you will get to a point where it starts to go back down. Once you get there, you have reached the knock threshold. Richen it back up a percent or 2 or so, and keep an eye on the timing, and you'll proably run pretty well.

Also, you'll find it's easier to tune at a lower boost level. 15 psi isn't bad, but if you can turn it down a tad more, it might be even easier.

....Kyle T.

 

[mitsugsx95]

Well, I did another pull after I i leaned it out about -2%. Timing is still climing, but only up to 18. There were no dips in timing and o2 volts held at about .96. From 3-4.5 rpms, it feels a little bumpy, but after 5k, its really smooth.
As for the low, I tried tuning it from a drive. After I got everything 0 out. I left it there. After about a 10min drive, I had my LTFT go up to 5%. So im not sure what that means.

 

[kpt4321]

If your LTFT went up, that means that your SAFC settings are too lean. Add a percent or two to the lo throttle table and see what happens.

If you were getting 19 degrees, and now you're only getting 18, then you need to slowly richen it back up until you get maximum advance.

....Kyle T.

 

[EuroGSTSpyder]

so what are the timing suposed to be at for best value? I am geting to tunem y car now and just wanna know ahat to look for?
I think my timing ended up at 24 at most when I did a full pull on third gear from 2500RPM all the way to redline...is that too high?

 

[mitsugsx95]

Originally posted by EuroGSTSpyder
so what are the timing suposed to be at for best value? I am geting to tunem y car now and just wanna know ahat to look for?
I think my timing ended up at 24 at most when I did a full pull on third gear from 2500RPM all the way to redline...is that too high?

24 is too high. You should be able to lean it out a lot. I've gathered that somewhere around 19deg of timing, with good base timing, is what you are looking for.

 

[nine5raptor]

24 is not too high. a lot of things determine what too high is (the point where you blow the headgasket most likely) if timing continues to increase as you lean it out, then you are good, if it starts dropping, go back the other way.

 

[mitsugsx95]

Thats what I meant. If he's getting 24deg of timing in the top of third, he has some room to lean it out and bring it down a little. With a big 16g and 660's, he should be able to lean it out to around 20, and still have good timing advance.

 

[nine5raptor]

lean it out to around 20??? I think I am missing something. 24 deg is better than 20. and leaning it farther would not be a good thing unless timing goes up.

 

[ILOSE]

There comes a point where too much timing has a little effect. But it allows you to lean out the motor or add more boost to bring timing down. You'll be able to make more power on a leaner car with let's say 19 degress timing then a car running rich and making 25 degress.

 

[nine5raptor]

There was a conversation about this about 6 or 8 months ago in one of the forums (before they changed them) and the general consensus was the other way around: that a rich car with more timing will make more power than a leaner car with less timing.

 

[EuroGSTSpyder]

well I can say my car is runing rich sine I even smell fuel of the exhausts..** Na seriously...I have the A/F right now..( no logger yet) and it sits all the way to the bottom (last green led )when I am at wot so ....Will tune with the new turbo and all when I get it here so you can get a new log to lok at....

My timing however never drops or gets wacky,its a steady climb from 2700RPM and 9-10 dgr to 7000RPM and 24-25dgrs in timing.Keps climbing nice and smoothly.

Hmm..need to log asap so I can tuneit in better again..*S* And hope for a logger to come soon! I need some cables for it really....nothing else...wellwell...in time...

 

[nine5raptor]

Without a logger, how do you know what your timing is doing?

 

[Kevin Jewer]

Keep in mind that as you lean out on the AFC, the reported airflow goes down, and the ECU will allow more timing. Until you knock of course. This is what Kyle meant a few posts back. So if he is getting 24, ad he leans out it will actually go up. Until he knocks, and that is a bad way to reduce timing 24 is considered good for a 1g, and is rarely seen on a 2g. The people that are better off with less timing are people that are flowing a lot more air than the origianl poster is. At lower airflow values, it is much safer to run more timing, and is quite productive. Somewhere over 35-40 pounds/minute though, trying to get that much timing is a lost cause IMO, and you are better off in the low 20s, tuned a bit rich to accomodate the higher cylinder pressures that come with high airflow values.

 

[EuroGSTSpyder]

Ok so I borowed a logger to get my first timing numbers..Now I got my own and I can give you correct numbers....I will psot a log soon enough for you to see...

I am still on y 440's not the 660s...They are in my room waiting for me to learn the SAFC and tuning part before I throw them on..Dont wanna mess withs tuff til I know wat I am doing basicly...

I am reading every post about STFT and LTFT and SAFC tuning to be able to do this myself but for now I have a few Q so I will probably be back agin**

 

[Hooah]

just had a quick basic question....when your doing the adding thing for the low trims say you have a short trim of 3 and a long term of 8 at 1000 rpm...you would have 11 so you would put the safc to -11% correct? thanks

 

[kpt4321]

No. The percentages on the SAFC do not correlate directly to the percentages that are the fuel trims. A couple percent on the SAFC wil do a lot for the fuel trims.

...Kyle T.

 

[kpt4321]

Originally posted by 95GSXracer
Somewhere over 35-40 pounds/minute though, trying to get that much timing is a lost cause IMO, and you are better off in the low 20s, tuned a bit rich to accomodate the higher cylinder pressures that come with high airflow values.

Case in point:

Andre just dyno'd his car again, and he made 466 or so whp on pump gas. He runs about 26 psi of boost, and timing advance in the low teens. He has found that gives him the best power on pump gas and the higher boost levels he is running.

The octane of the fuel you are using will vastly change the "best" timing to run also. Because race gas burns so much slower than pump gas, you need to advance the timing more in order to have the combustion occur at the proper place in the piston's travel. Pump gas burns more quickly, and thus you need less timing advance to have the "boom" go down at the right time.

...Kyle T.