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Unclemeaty · 02-14-2011, 11:12 PM

I found out two great things tonight. One of which I must place my forehead firmly against the palm of my hand while grinning stupidly. My air-filters are original equipment with original miles on them; they need to be replaced... but instead of pumping any money into replacement filters, my intention is to get a full CAI. Tonight when I checked my stock filters, I found 2 large brown leaves stuck in front of one filter, and one larger brown leave stuck in front of the other! The engine actually sucked them up into the airbox where the stock filters had them likely blocking airflow. I have not much idea how long they were sitting there for... Am glad I found them, but now I gotta do a few more high-RPM pulls to see if my latest street tune is still acurate. I feel like a dummy!!! Yet I'm happy I might get more outa this motor in stock form. I'm thinking even if the leaves were closing off 5% of the possible airflow then there would be a positive result to come from their removal.

The second thing I noticed is really very important. While running hard, the Radio Shack Mini-Amp will 'tweet' when there is pinging, but if it only tweets for the briefest of moments its sort of tough to discern. When there is pinging present, I notice the Cipher trace on the timing maps takes a 1 block step to the left. My best resolve is the ECU is more in tune with itself than I am with the Mini-Amp, for even the slightest degree is noticed by the ECU and not through the amp. Although this could be because I'm only monitoring knock from bank 1, the engine is retarding both scheduled fuel, ignition, and probably throttle to some degree as well. I was able to stabilize the timing trace by adding 1-2 ticks of fuel, and subtracting 1 point of the Timing_Low_Det map. From 6500-7500 RPM my engine likes ~67-68 on the timing maps and 12.3:1 AFR. That gives me +-27 degrees of timing advance.

So, if you are road tuning, it is very important if you see the timing trace step left while running her up, this is likely indicative of engine ping and the ECU is pulling back.

02-14-2011, 11:12 PM	#45 (permalink)
Unclemeaty Base Member Join Date: Aug 2010 Location: Atlanta Posts: 203 Drives: 150cc Scooter Rep Power: 15	I found out two great things tonight. One of which I must place my forehead firmly against the palm of my hand while grinning stupidly. My air-filters are original equipment with original miles on them; they need to be replaced... but instead of pumping any money into replacement filters, my intention is to get a full CAI. Tonight when I checked my stock filters, I found 2 large brown leaves stuck in front of one filter, and one larger brown leave stuck in front of the other! The engine actually sucked them up into the airbox where the stock filters had them likely blocking airflow. I have not much idea how long they were sitting there for... Am glad I found them, but now I gotta do a few more high-RPM pulls to see if my latest street tune is still acurate. I feel like a dummy!!! Yet I'm happy I might get more outa this motor in stock form. I'm thinking even if the leaves were closing off 5% of the possible airflow then there would be a positive result to come from their removal. The second thing I noticed is really very important. While running hard, the Radio Shack Mini-Amp will 'tweet' when there is pinging, but if it only tweets for the briefest of moments its sort of tough to discern. When there is pinging present, I notice the Cipher trace on the timing maps takes a 1 block step to the left. My best resolve is the ECU is more in tune with itself than I am with the Mini-Amp, for even the slightest degree is noticed by the ECU and not through the amp. Although this could be because I'm only monitoring knock from bank 1, the engine is retarding both scheduled fuel, ignition, and probably throttle to some degree as well. I was able to stabilize the timing trace by adding 1-2 ticks of fuel, and subtracting 1 point of the Timing_Low_Det map. From 6500-7500 RPM my engine likes ~67-68 on the timing maps and 12.3:1 AFR. That gives me +-27 degrees of timing advance. So, if you are road tuning, it is very important if you see the timing trace step left while running her up, this is likely indicative of engine ping and the ECU is pulling back. Last edited by Unclemeaty; 02-14-2011 at 11:21 PM.