Did some logging today - 020, 026, 115, all that fun stuff
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Did some logging today - 020, 026, 115, all that fun stuff
First, because I was curious, I logged 020 and 026 together - Lemmi settings were 1% pulled primary fuel (still rich), .75 timing advance, 83% SEL. The key is in order of cylinder 1-4 (first in list in 1, etc.). The main thing I noticed is my CF's were almost never over 10, but the voltages were in the 20-25 range a fair amount:
<img src="http://www.twoturbos.com/logs/block020-026-.75T.gif">
Here is the same graph, but with timing pushed to 1.5. That initial spike I think is caused by the spike in boost. I'm getting some really weird boost, and I basically think the N75 sucks at controlling it, so I might just go straight MBC:
<img src="http://www.twoturbos.com/logs/block020-026-1.25T.gif">
I then logged boost and KV together - time stamps vary a bit so I threw them into separate graphs:
<img src="http://www.twoturbos.com/logs/boost.gif">
<img src="http://www.twoturbos.com/logs/knock.gif">
<img src="http://www.twoturbos.com/logs/block020-026-.75T.gif">
Here is the same graph, but with timing pushed to 1.5. That initial spike I think is caused by the spike in boost. I'm getting some really weird boost, and I basically think the N75 sucks at controlling it, so I might just go straight MBC:
<img src="http://www.twoturbos.com/logs/block020-026-1.25T.gif">
I then logged boost and KV together - time stamps vary a bit so I threw them into separate graphs:
<img src="http://www.twoturbos.com/logs/boost.gif">
<img src="http://www.twoturbos.com/logs/knock.gif">
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While watching the game, I reply...
Seems like you're reaching KV saturation and pullback on cylinder 2. Cyl5 is also a problem child, you should log that as well.
Why though?
I know you have some chronic timing problems and am curious as to why. Any aftermarket motor mounts ? Any problems with anything rubbing or hitting? Spark plug type? Any ECUx logs? If you don't have it, I think you should get it so you can log EVERYTHING at once to see wtf is going on here.
Hope this helps,
-Mike
Why though?
I know you have some chronic timing problems and am curious as to why. Any aftermarket motor mounts ? Any problems with anything rubbing or hitting? Spark plug type? Any ECUx logs? If you don't have it, I think you should get it so you can log EVERYTHING at once to see wtf is going on here.
Hope this helps,
-Mike
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You need to buy a wide band 02 sensor.
You are tuning blind man.
Stock 02 sensors are not reliable and something could be messing with your knock sensor like mike suggested. But, you could also just be running lean and causing your engine to knock..... Thus your timing problems. Wide band time.
That and I don't think your N75 valve is the problem..... Many Stage III cars run around just fine with a stock N75 valve and it is as smooth as stock.... Me included. Unless your N75 is not working properly, I doubt it is the problem.<ul><li><a href="http://www.extremepsi.com/store/customer/product.php?productid=17337&cat=0&page=">W ide Band 02.....</a></li></ul>
Stock 02 sensors are not reliable and something could be messing with your knock sensor like mike suggested. But, you could also just be running lean and causing your engine to knock..... Thus your timing problems. Wide band time.
That and I don't think your N75 valve is the problem..... Many Stage III cars run around just fine with a stock N75 valve and it is as smooth as stock.... Me included. Unless your N75 is not working properly, I doubt it is the problem.<ul><li><a href="http://www.extremepsi.com/store/customer/product.php?productid=17337&cat=0&page=">W ide Band 02.....</a></li></ul>
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Thanks, I'm actually starting to think something is rubbing
Jon (X-1) was in my car and pointed out that a vibration I have during hard throttle could be the exhaust or something rubbing. The engine definitely does not feel smooth when I'm getting on it, and I think something could be causing the higher knock.
Once Streetwerke gets the dyno, I think we'll be able to more scientifically narrow down the variables.
Once Streetwerke gets the dyno, I think we'll be able to more scientifically narrow down the variables.
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Had a wide band on yesterday, was running rich, and no amount of Lemmi tweaks did anything
We pulled 20% fueling and the ratios stayed the same...
The N75 is working fine, I just think it's too slow and oscillates too much. The boost spikes up, the engine thinks its going to knock a lot, so it pulls boost way down, then realizes it overcompensates and goes back up. I'd much rather tune with an MBC and control it all myself. BrammelS4, X-1 and I yesterday all agreed no one should expect to have great power and smooth delivery, it's just not going to happen on these cars.
The N75 is working fine, I just think it's too slow and oscillates too much. The boost spikes up, the engine thinks its going to knock a lot, so it pulls boost way down, then realizes it overcompensates and goes back up. I'd much rather tune with an MBC and control it all myself. BrammelS4, X-1 and I yesterday all agreed no one should expect to have great power and smooth delivery, it's just not going to happen on these cars.
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Based on those logs, I'd put timing back to default and add some boost back.
91 craptane and lots of timing are mutually exculsive, unless you do hot side mods.
On another note, your requested boost curve seems very odd to me (spike, drops down, gradually increases as RPM increases).
Like Mike said, you can figure out a lot more if you log with ECUx. If mine worked, I'd go log. Damn APR <Ctrl 7>
On another note, your requested boost curve seems very odd to me (spike, drops down, gradually increases as RPM increases).
Like Mike said, you can figure out a lot more if you log with ECUx. If mine worked, I'd go log. Damn APR <Ctrl 7>
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Yah, I think SEL scaling is doing that - I'm going to put it back to 100 and control with MBC
And I agree, I'll go back to how I had it before, but I think we are learning some interesting stuff. I think 91 octane tuning is tricky, especially given we dont have the ability to adjust variables at different load/rpm points...