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View Full Version : An evening with timing advance...



MrBluGruv
08-12-2009, 02:05 PM
So currently I have an xCal3 with a tune from Lidio, and a friend and I were discussing ways to wring out some more power and landed on the idea of advancing the ignition timing mostly for the immediacy and bang-for-buck. After a looooong process of stepping up the timing by 1 degree at a time testing revs and pulls each degree each time I stopped at 6 degrees (+4 global spark, +2 in each respective RPM band) and decided I wouldn't push the envelope any more, and adjusted the WOT AFR to "2.0 leaner" setting. I heard no knocking or pinging ever, temps seemed fine all evening, basically no funny sounds or smells or heat the entire time I ran it. The feeling was phenomenal, something that I would've expected to get from the tune as it would've come directly from the tuner, 2nd gear could pull me from 40 to 80 quite quickly, every gear had strong pull even without dipping too far into the throttle, even launches from a stop were NOTABLY quicker. Currently my only modifications aside from that tuner setup is no cats to custom mufflers and a JLT intake, and I run only 93 octane Valero gas(mostly for fuel purity reasons as I've heard of some other stations sneaking ethanol into their mix and also heard Valero doesn't, just what I've heard...).


My point to this thread, I've read a lot of threads saying to stay the hell away from the timing setting on the xcals cause the motor just can't handle much any advancement, but I've looked and listened for everything I could imagine besides directly trying to read the knock sensor through the computer or using a wideband, so what am I missing? For lack of better phrasing, why did this work and why was I able to get away with it? Would the knock sensor pull THAT much timing if this was being problematic?

After that night I switched it back to the canned Lidio tune for safety's sake, and I'm curious now what else I should be looking for if I was to slowly begin advancing my timing again. Is there serious possibility that the motor would kill itself without any audible or sensor signs of knock or heat or stress otherwise?


(yes, feel free to call me a moron for pushing it that far, but I'm learning and would appreciate some positive feedback and info to learn from too.)

Stranger in the Black Sedan
08-12-2009, 02:19 PM
Were you gathering data from the track, dyno, gtech, etc? I hope you are relying on more than seat of the pans for tuning, especially without a wideband

ImpalaSlayer
08-12-2009, 02:24 PM
the knock sensors are there to pull timing, just cuz you add it in the tuner dosent mean you will get it if the knock sensors sence knock

MrBluGruv
08-12-2009, 02:44 PM
yeh I know, that's why I was curious because if I'm to believe the general consensus in threads on the subject of advancing timing adding that much timing should've easily created knock, but there didn't appear to be any, so I guess that answers my question about the knock sensors working hard and retarding the timing (if there was indeed knock present). So then I guess my question becomes this on the subject: how much will the knock sensors retard the timing if they detect it? As far as necessary? If that's the case, basically functioning knock sensors would mean one wouldn't really have to worry about timing too much (although I don't plan on getting to that far timing advance again, if even that much)

judging from what I've read on the forum, the fuel mapping seems to be great from the factory on this car so if I go back and modify the timing the WOT mixture is being left alone.

i'm still curious though, aside from getting a hold of a wideband meter, what i'm a looking and listening for apart from knock and temperature hike?

Stranger in the Black Sedan
08-12-2009, 03:02 PM
The amount of timing and how fast it is pullled is based on many factors. You will hurt performance by running into the knock counts because the sensor will pull more timing than you could have gotten away with running the appropriate amount of timing. If you have a tune that is running heavily into the knock sensor, it is not much of a tune.

MrBluGruv
08-12-2009, 03:46 PM
Ahh, well that gives me a little bit of confidence, as if this is the case then I guess I hadn't pushed it too far, the settings I had dialed in were a HUGE improvement over what came with the xcal when I bought it.

Taking into account I not push radically advanced timing, could I realistically have a timing that was both too far for the knock sensors to correct before serious damage, let alone cause enough damage fast enough that I couldn't shut off the motor and retard timing back to a safer setting?

Krytin
08-13-2009, 06:13 AM
I'm not familiar with the XCal3. Can you Data Log with it and if you can can you log the knock sensor(s) during a "run"?

MrBluGruv
08-13-2009, 08:48 AM
It does some data logging but I don't think that's one of the things it can log that.

I'm actually looking into a piece of equipment called the DashDyno, it's a lot like the ScanGaugeII but a little larger and with some pretty extensive data logging and calculation abilities, and can be connected as a middle-man directly to a laptop to do it all via software.

ImpalaSlayer
08-13-2009, 12:32 PM
It does some data logging but I don't think that's one of the things it can log that.

I'm actually looking into a piece of equipment called the DashDyno, it's a lot like the ScanGaugeII but a little larger and with some pretty extensive data logging and calculation abilities, and can be connected as a middle-man directly to a laptop to do it all via software.


sounds nifty, i have the scan gauge and it shows me timing...... just not as much as i wana see :depress: