Tuning Help - Timing Related

[RedlinedTSi]

When I log my car I notice that my timing falls off when I floor it, which I expect, and then recovers up to around 6K rpms, but then it starts falling off again to redline. What would cause this? I can post more of the log if needed. Thanks.

 

[FastRthenU]

Probley getting high knock counts. Then the ecu is pullin timming out for protection. What are your fuel trims like? Try adding more fuel were your losing timing/or knockin

 

[RedlinedTSi]

Yea, my knock increases at that point. My high fuel trim is at 92, so that shows a little rich. My O2s borderline safe, at .86 or .84. My injector duty cycles are way past 100%, but I didn't think about getting bigger injectors because I'm still on the 14b. I've tried messing with my boost at either 15 or 17 but it doesn't make any big difference. My fuel mods consist of a rewired Walbro 255, Stevetek style fuel line, and a Buschur/SX AFPR at 43psi. I'm tuning with a MAFT and just can't get it right.

 

[tsitalon1]

Sounds like heat soak to me !!!

By chance is this more prone to happening in like 3 & 4th gear ?
2nd gear is much better right ?

btw what boost are you running ?
JAmes

 

[RedlinedTSi]

I usually do my logs in 3rd gear. Never tried them in 2nd before, so I don't know. Right now it's at 17, but I've tried it at 15 too and it didn't look that much different.

 

[tsitalon1]

I still think it's heat soak.

Also try checking for boost leaks. You might be overboosting your turbo to make 17psi.

You can also try taking your pass side headlight out with the headlight in the up position to try to get some cooler air. If knock goes down it is heat soak..

Also try freezing your ic with a can of r134 a/c before your 3rd gear run.. that will also tell you if it's heat soak.

Good luck,
James

Keep me informed.

 

[tsitalon1]

forgot Check base timing too

 

[whitegst97]

I have a couple of questions my self, i dont' really know how old this thread is but i hope someone could help me, if im jmping in in someone else's thread , sorry, please let me know,

I need a little bit of help here, people that really spend time tuning 2G's with a datalogger, perhaps you could give me a couple of hints. I just did a couple of pulls and tuned to get the most timing advance possible, i can't get it passed 16 maybe 17 at 7k. The 02's in the datalogger read rich, about .98 but if they go lower the timing decreases, and i also heard that the datalogger 02 readings aren't that accurate they are always a bit higher than normal. So here are a couple of runs, tel me what you think, this was at 17 psi. i also lowered the boost to 15 and it was about the same.

RPM Timing 02's
0.3 2552.0 29.0 0.82 -0.78
0.58 2684.0 18.0 0.96 0.0
0.87 2852.0 21.0 0.94 0.0
1.15 3020.0 19.0 0.94 0.0
1.43 3200.0 20.0 0.94 0.0
1.71 3404.0 17.0 0.92 0.0
1.99 3612.0 16.0 0.94 0.0
2.28 3844.0 13.0 0.94 0.0
2.56 4064.0 4.0 0.96 0.0
2.84 4408.0 10.0 0.98 0.0
3.13 4744.0 9.0 0.98 0.0
3.42 5124.0 8.0 0.98 0.0
3.7 5460.0 8.0 0.98 0.0
3.98 5960.0 11.0 0.98 0.0
4.26 6028.0 13.0 0.98 0.0
4.54 6376.0 15.0 0.98 0.0
4.82 6724.0 15.0 0.98 0.0
5.11 6968.0 15.0 0.98 0.0
5.4 7204.0 16.0 0.98 0.0


RPM Timing 02's
3.4 2508.0 27.0 0.86 0.0
3.68 2644.0 20.0 0.94 0.0
3.96 2804.0 20.0 0.94 0.0
4.24 3000.0 19.0 0.92 0.0
4.52 3188.0 17.0 0.92 0.0
4.81 3368.0 16.0 0.94 0.0
5.09 3592.0 15.0 0.92 0.0
5.39 3852.0 11.0 0.94 0.0
5.67 4136.0 10.0 0.96 0.0
5.95 4420.0 10.0 0.96 0.0
6.23 4776.0 9.0 0.98 0.0
6.52 5120.0 9.0 0.98 0.0
6.8 5508.0 8.0 0.96 0.0
7.08 5824.0 10.0 0.98 0.0
7.37 6132.0 13.0 0.98 0.0
7.65 6452.0 14.0 0.98 0.0
7.94 6748.0 14.0 0.98 0.0
8.22 7032.0 15.0 0.98 0.0
8.51 7312.0 16.0 0.98 0.0

 

[tsitalon1]

Sorry I'm a 1g guy

 

[RedlinedTSi]

Heat soak is possible cuz I'm still on the stock SMIC, but I don't have the funds for an upgrade right now. Base timing SHOULD be right cuz I did the timing belt last and set it. I've had my car for over a year and really never checked for boost leaks. I'm probably gonna go for that one and get a leak tester. Thanks.

 

[tsitalon1]

No problem

Good luck
James

 

[kpt4321]

WhiteGST- Those logs look decent, it looks like timing is increasing as you get towards redline. 2g's won't ever get as much timing advance as 1g's, 17 degrees is pretty good.

 

[Phoenyx]

Originally posted by kpt4321
WhiteGST- Those logs look decent, it looks like timing is increasing as you get towards redline. 2g's won't ever get as much timing advance as 1g's, 17 degrees is pretty good.

True, but his timing is terrible in the mid-range (4k-5k). You must be knocking at that range. Try turning the boost to stock and see what your readings are.

It will be hard for you to tweak at certain rpms without a SAFC.

-M

 

[whitegst97]

Well i do have an AFC, i've been told that the timing in the 2gs goes down a lot when the Accel. is punched, or when the turbo starts to boost, the boost is at 16 psi right now,