Just started tuning w/ MAFT and logger. HELP!

99gst_racer · 05-17-2005, 07:08 PM

I recently installed my new turbo (T04b v-trim), MAFT blow-thru, 650cc injectors, and Key driver chip. I'ma also relativily new to my datalogger.... I cant seem to get my timing curve to even look good, let alone be perfect.

If anyone is very familiar with the MAFT translator, please feel free to chime in. I got the car to idle good and it seems to be driving OK too. It was better on stock injectors though. Here's my log I just took today.

5/17/05-20:11:51 - Obd2
Time,RPM,Timing,O2 1 Bank 1

00:03.56, 1252.0, 13.0, 0.82
00:04.76, 1416.0, 21.0, 0.86
00:05.94, 1400.0, 21.0, 0.58
00:07.13, 2484.0, 23.0, 0.0
00:08.32, 3576.0, 14.0, 0.02
00:09.52, 1576.0, 7.0, 0.9
00:10.71, 3296.0, 9.0, 1.0
00:11.89, 5316.0, 19.0, 0.96
00:13.09, 7708.0, 39.0, 0.6
00:14.27, 5032.0, 16.0, 0.92
00:15.46, 6084.0, 19.0, 0.94
00:16.64, 6980.0, 15.0, 0.94
00:17.84, 5296.0, 35.0, 0.84
00:19.03, 3504.0, 16.0, 0.96
00:20.21, 3572.0, 9.0, 1.0
00:21.39, 2772.0, 9.0, 0.06
00:22.60, 2988.0, 34.0, 0.9
00:23.78, 2896.0, 23.0, 0.0
00:24.96, 2800.0, 23.0, 0.0
00:26.15, 2716.0, 30.0, 0.06
00:27.35, 2692.0, 30.0, 0.78

I'm wondering why at 7708 RPM's, I have a 39 for timing..... And seconds later, at 6980 RPM's, I have a decent number of 15. I am only tuning with the translator, and I'm still learning about it. Can someone knowledgable on tuning please chime in and help me out. Educate Me!!!

CanadianTSi · 05-17-2005, 08:39 PM

Just do a 3rd gear pull from 2.5 to 7k.

99gst_racer · 05-17-2005, 09:32 PM

OK, here's my 3rd gear pull. Before I did the pull, I made one change to the translator. I change my WOT setting from -25% to -20%. This log looks much better.

5/17/05-23:02:13 - Obd2
Time,RPM,Timing,O2 1 Bank 1

00:00.72, 2856.0, 9.0, 0.96
00:01.43, 3016.0, 9.0, 0.98
00:02.14, 3200.0, 8.0, 1.0
00:02.86, 3392.0, 6.0, 0.98
00:03.57, 3640.0, 8.0, 0.96
00:04.28, 3916.0, 10.0, 0.94
00:05.01, 4232.0, 14.0, 0.88
00:05.73, 4516.0, 13.0, 0.9
00:06.44, 4840.0, 13.0, 0.92
00:07.15, 5144.0, 14.0, 0.94
00:07.86, 5452.0, 14.0, 0.94
00:08.57, 5748.0, 16.0, 0.94
00:09.28, 6016.0, 17.0, 0.94
00:10.01, 6264.0, 20.0, 0.94
00:10.72, 6472.0, 19.0, 0.94
00:11.44, 6712.0, 20.0, 0.94
00:12.15, 6904.0, 20.0, 0.94
00:12.86, 7056.0, 17.0, 0.94
00:13.57, 7228.0, 19.0, 0.92
00:14.30, 7368.0, 18.0, 0.94
00:15.01, 5340.0, 19.0, 0.68
00:15.72, 3472.0, 35.0, 0.7
00:16.45, 2012.0, 23.0, 0.0
00:17.15, 1020.0, 13.0, 0.0
00:17.87, 1060.0, 16.0, 0.04
00:18.59, 1180.0, 9.0, 0.08
00:19.29, 1244.0, 11.0, 0.86

What do you think? I just put the 650's in 2 days ago. Until now, I've been running stock injectors and it was running really good actually. I'm only at 12 lbs. right now, but will be turning it up to 20-22 PSI (hopefully) by the end of the week. I just need to increase my tuning skills a little bit before I go cranking up the boost too much.

Hows this log look? What needs to be better? Thanks in advance.

CanadianTSi · 05-17-2005, 09:43 PM

looks like you go a bit lean around 4k, I would add some fuel there.

99gst_racer · 05-17-2005, 09:50 PM

Quote:

Originally Posted by CanadianTSi

looks like you go a bit lean around 4k, I would add some fuel there.

Forgive me if my questions sound "newbie-ish". I just want to make sure I understand everything correctly. To richin it up around 4K, I would want to make a change to the MID control, right? It is currently set at 30%. What would you recommend changing it to? Thanks for the help.

TimG · 05-17-2005, 10:23 PM

You can't tune with a stock O2 sensor housing well enough to validate the interpretation of the sensor reading a few volts less then the other rpm ranges. I'd like to see what the log looks like under the guidance of a wideband.

Just make sure you aren't knocking and take the general average of the O2 sensor using the fuel trims to tune conservatively now.

99gst_racer · 05-17-2005, 10:34 PM

Quote:

Originally Posted by TimG

I'd like to see what the log looks like under the guidance of a wideband.

Yeah, you and me both. I'll see if I can get ahold of one within the next 2 weeks.

Quote:

Originally Posted by TimG

Just make sure you aren't knocking

I have the knock sum gauge where the factory boost gauge is. One of the Keydriver features... Are they at all accurate? I'm not getting any high readings on it......

Quote:

Originally Posted by TimG

and take the general average of the O2 sensor using the fuel trims to tune conservatively now.

How should my STFT and LTFT look?

hakcenter · 05-17-2005, 11:15 PM

Quote:

Originally Posted by 99gst_racer

I have the knock sum gauge where the factory boost gauge is. One of the Keydriver features... Are they at all accurate? I'm not getting any high readings on it......

What options are there for the factory boost gauge?
Let's face it, the factory boost gauge is pretty useless! It only looks at the amount of corrected airflow, and takes a guess at what the boost is! By now you should have purchased a proper boost gauge, so let's do something useful with the old boost gauge (you can choose ONLY one): Knock sum - On DSM's, the gauge will normally rest on the "-7", for 0 knock sum. It will rise 5 knock sum per division on the gauge, so "0"=5 knock sum, "+7"=10 knock sum, and "+14"=15 or more knock sum. On GVR-4's, the knock sum is displayed as 5 knock sum per LED. O2 - In this mode, the gauge will give you a quick indication of whether you are in closed-loop or open-loop operation. The center of the gauge ("0") is roughly .50 volts, and the needle should swing back and forth around this point during normal closed-loop operation. The highest mark on the gauge represents approximately .90 volts. Or, if you choose, the boost gauge can be left alone, its up to you.

I'm not sure about 2nd Gens, but it probably works well.

99gst_racer · 05-18-2005, 06:00 PM

OK, I was just prcticing my holeshots to see where I want my 'selectable launch RPM' set at, and I decided to log one of them. Check this out. (I seperated it where I shifted, 1st through 3rd gears)

5/18/05-19:06:33 - Obd2
Time,STFT,LTFT,RPM,Timing,O2

00:01.18, 0.0, -4.0, 2932.0, 26.0, 0.0
00:02.36, 0.0, -4.0, 1824.0, 5.0, 0.92
00:03.55, 0.0, -4.0, 3044.0, 10.0, 0.98
00:04.76, 0.0, -4.0, 4828.0, 19.0, 0.94
00:05.94, 0.0, -4.0, 7528.0, 39.0, 0.58

00:07.13, 0.0, -4.0, 4852.0, 16.0, 0.94
00:08.31, 0.0, -4.0, 5972.0, 21.0, 0.94
00:09.52, 0.0, -4.0, 6940.0, 22.0, 0.94

00:10.69, 0.0, -4.0, 4720.0, 21.0, 0.86
00:11.88, 0.0, -4.0, 5288.0, 16.0, 0.94
00:13.06, 0.0, -4.0, 5696.0, 19.0, 0.94
00:14.27, 0.0, -4.0, 6084.0, 20.0, 0.94
00:15.44, 0.0, -4.0, 6472.0, 17.0, 0.94
00:16.63, 0.0, -4.0, 6784.0, 18.0, 0.94
00:17.84, 0.0, -4.0, 7056.0, 19.0, 0.94

Whats up with my timing and O2 reading at the end of 1st gear? What would cause it to look so nasty? Also, how do my fuel trims look?

44pirate · 05-18-2005, 06:38 PM

I assume your using a pocket logger. You will only get like 11data points at a time, so only log 3 items, rpm, timing and O2, at a time.

When your trying to get your STFT in line, before you make a change on the MAFT reset your ECU, a 2g compensates rather quickly. I found that I got a better STFT tune this way.

Since you have the keydiver knock indicator, what I would do is just log rpm and timing and eyeball the knock guage as I'm going through the rpms. If it's not knocking then the hell with O2's. It's all in the timing as you go through the rpm's.

99gst_racer · 05-18-2005, 08:02 PM

Quote:

Originally Posted by 44pirate

I assume your using a pocket logger. You will only get like 11data points at a time, so only log 3 items, rpm, timing and O2, at a time.

When your trying to get your STFT in line, before you make a change on the MAFT reset your ECU, a 2g compensates rather quickly. I found that I got a better STFT tune this way.

Since you have the keydiver knock indicator, what I would do is just log rpm and timing and eyeball the knock guage as I'm going through the rpms. If it's not knocking then the hell with O2's. It's all in the timing as you go through the rpm's.

Yeah, I'm using the pocketlogger. I usually only do log RPM, Timing, and O2's. I just wanted to see my fuel trims this time around..... (i'm still experiencing with my logger. i've only had it for a couple weeks)
My keydriver knock sum gauge satys at 0 all the time, which I believe is indicating a knock count of 5 (right?).

CanadianTSi · 05-18-2005, 10:09 PM

Quote:

Originally Posted by 99gst_racer

Whats up with my timing and O2 reading at the end of 1st gear? What would cause it to look so nasty? Also, how do my fuel trims look?

It's goes like that for the instant when your off the throttle shifting...

As for your fuel trims, check them under idle and while cruising at steady rpms not WOT.