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Killa_dsm

15+ Year Contributor
2,162
19
Aug 31, 2004
Bay Area, California
Hey, so I finally got some larger injectors (Evo 560cc) and I was planning on tuning it. So I need your guys help.

Setting on High AFC:
1k -13
2k -13
3k -16
4k -15
4.5k~7k -16

Log: Big16g, 17psi.
Fuel: 560cc/ VR4 fuel pump

Rpms: 2500 O2: 0.96 TPS: 96 Timing 22
Rpms: 2612 O2: 0.96 TPS: 96 Timing 19
Rpms: 2744 O2: 0.94 TPS: 96 Timing 16
Rpms: 2892 O2: 0.94 TPS: 96 Timing 13
Rpms: 3048 O2: 0.94 TPS: 96 Timing 10
Rpms: 3232 O2: 0.96 TPS: 96 Timing 8
Rpms: 3444 O2: 0.97 TPS: 96 Timing 6
Rpms: 3652 O2: 0.97 TPS: 96 Timing 7
Rpms: 3860 O2: 0.97 TPS: 96 Timing 8
Rpms: 4076 O2: 0.97 TPS: 96 Timing 7
Rpms: 4288 O2: 0.97 TPS: 96 Timing 8
Rpms: 4472 O2: 0.97 TPS: 96 Timing 8
Rpms: 4652 O2: 0.97 TPS: 96 Timing 9
Rpms: 4848 O2: 0.97 TPS: 96 Timing 10
Rpms: 5004 O2: 0.97 TPS: 96 Timing 10
Rpms: 5224 O2: 0.97 TPS: 96 Timing 11
Rpms: 5408 O2: 0.97 TPS: 96 Timing 10
Rpms: 5556 O2: 0.97 TPS: 96 Timing 11
Rpms: 5712 O2: 0.97 TPS: 96 Timing 13
Rpms: 5888 O2: 0.97 TPS: 96 Timing 13
Rpms: 6036 O2: 0.97 TPS: 96 Timing 15
Rpms: 6180 O2: 0.97 TPS: 96 Timing 15
Rpms: 6324 O2: 0.97 TPS: 96 Timing 15
Rpms: 6452 O2: 0.97 TPS: 96 Timing 12
Rpms: 6584 O2: 0.97 TPS: 96 Timing 13

Yeah I think I’m knocking a little, but I’m new to tuning and hoping to learn.
Later on I want to run more boost if I can but I’m just trying to figure out how to tune everything properly first. Aren’t some of the AFC setting suppose to be in the + range? Does this mean I can up the boost and add more fuel? I know all cars are different but does anyone have any suggestions on how much boost to run and some settings for the AFC just to start off with?

Do you think it’s possible to run around 19~20psi safely on this set up?

Thanks
 
A couple of things to check before we get down to the tune. What is the gap on your plugs? Did you do a leak check?

Your running rich, and your timing isn't climbing as high as it should, but you have a good base. Go ahead and lean it out to about -18% across the Hi Throttle Map and make another pull.

Only log RPM, Timing, O2 and Airflow. Then post that bad boy up. :rocks:
 
My good friend Still_Good had some thoughts, but because he has never really posted here (despite being registered for quite a while) he can't post in this forum. Here are his thoughts:

Alright,

The key indicator in this case is your timing advance. At 2744rpm you have 16 degrees of advance -- now to this point you should expect your timing to be dropping

As you TPS just went from whatever to WOT. That said, it should sit right about 16-22 degrees, depending on a variety of factors. (You're pulling out airflow with an AFC, so in all truth, you should be on the higher end)

The fact that timing continues to drop tells us that the ECU is seeing knock. It pulls timing and continues to retard it. Timing again begins to rise at 4800rpm, and works its way back to 15 degrees by 6324, but then falls again, indication that the knock sensor is still picking up something.

Knock can be caused by a variety of factors, often fueling related, but as has been pointed out intercooling also plays a large role in cooling, and therefore knock.

An important thing to note is that once the ECU pulls timing for knock, its going to be hard to tell exactly whats going on without logging knock directly.

Therefore, I'd start at the bottom of your powerband and try to "work up" in figuring out where the kinks are.

Note that knock appears when boost should begin to appear. Try playing with your fuel settings and see how it changes things -- at 3k rpms you go from being -13% to -16%.

As this is the area where it seems to be encountering problems, start with those #s.

Hope that helps some.
Zak

It's unfortunate that the 2g doesn't have an easy way to log knock the way that the 1g does. :(

Also, it might be a good thing to log the injector pulse width & duty cycle, as they can tell you quite a bit as well.
 
slugsgomoo said:
My good friend Still_Good had some thoughts, but because he has never really posted here (despite being registered for quite a while) he can't post in this forum. Here are his thoughts:

It's unfortunate that the 2g doesn't have an easy way to log knock the way that the 1g does. :(

Also, it might be a good thing to log the injector pulse width & duty cycle, as they can tell you quite a bit as well.

I might be reading your friends post wrong, but is he saying that the timing should be staying at 16 degrees and then climbing from there??? :confused:

With 550cc injectors the timing should drop to anywhere from 6 - 9 degrees at it's lowest point and then steadily rise to over 17 degrees. Most likely it will end up around -20 degrees.

The only timing pull I'm seeing occurs at 6254 rpm. The other pulls of 1 degree can be explained by IAT, current ECU airflow map, coolant temp increase, etc.

Also, you can't log IPW and IDC on a 2g without DSMLink.

CanadianTSi said:
Looks to me like your heatsoaking your stock IC, that's why you look rich but your timing is going down.

I thought that at first also, but I dismissed it because of the winter temperatures everyone is experiencing and the fact that he is only running 17psi. But you very well may be correct. :thumb:

I know that I am able to make about two 3rd gear pulls before my SMIC gets heatsoaked durning the summer, but then again, every car is different.
 
Its been awhile since I posted a log but here is another one. Running 19psi.

Rpms: 2564 O2: 0.96 Timing 14 Hz:6.67
Rpms: 2732 O2: 0.96 Timing 12 Hz:8.01
Rpms: 2884 O2: 0.96 Timing 9 Hz:9.86
Rpms: 3108 O2: 0.96 Timing 7 Hz:11.99
Rpms: 3316 O2: 0.97 Timing 6 Hz:14.67
Rpms: 3544 O2: 0.97 Timing 7 Hz:14.93
Rpms: 3780 O2: 0.97 Timing 8 Hz:15.86
Rpms: 4028 O2: 0.97 Timing 7 Hz:16.96
Rpms: 4260 O2: 0.97 Timing 7 Hz:17.94
Rpms: 4456 O2: 0.97 Timing 7 Hz:18.88
Rpms: 4688 O2: 0.97 Timing 7 Hz:19.56
Rpms: 4896 O2: 0.97 Timing 9 Hz:21.18
Rpms: 5056 O2: 0.97 Timing 10 Hz:21.56
Rpms: 5288 O2: 0.97 Timing 12 Hz:22.14
Rpms: 5476 O2: 0.97 Timing 10 Hz:23.15
Rpms: 5672 O2: 0.97 Timing 12 Hz:23.07
Rpms: 5824 O2: 0.97 Timing 13 Hz:24.26
Rpms: 6000 O2: 0.97 Timing 13 Hz:23.8
Rpms: 6172 O2: 0.97 Timing 13 Hz:25.11
Rpms: 6292 O2: 0.97 Timing 13 Hz:24.67
Rpms: 6440 O2: 0.97 Timing 14 Hz:25.12

This log doesn't look good, correct? Am i knocking? I think I added a little more fuel on the S-AFC but not sure I would have to take a look. Anyways does anyone have any suggestions on whether or not I should add more fuel? I want to run as much boost as I can safely. But I know the stock SMIC is a big restriction right now.

Well thanks!
 
I personally think you're running super rich, but you gotta watch out tuning without any way of controlling your timing as larger injectors skyrocket your timing the more you lean it out. Id say lean it out more and more until you have atleast 19-20degrees advance at 5500+rpm
 
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