Autotap Results - Analysis Wanted
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I finally broke down and ordered an auto-tap on Sunday night. I had it shipped next day air, so it went out on Monday and was at my house this morning.
I hooked it up and logged a whole bunch of WOT runs, and some partial throttle, all while out driving around for 30 minutes. This was in 80-90 temperatures with very high humidity. I had 2 other people in the car, plus air the condition on and off through out.
My intake temps ranged from 100-115F.
My car is a 2002 SSEi with 3.25 pulley, Thasher CAI, SLP 1.8 Roller Rockers, TOG Headers, and flexpipe. There is no u-bend. I also had half a tank of Sunoco Ultra 94.
The car currently has stock spark plugs.
I had several WOT runs throughout 1st and 2nd with 0 KR - and 9-11 degrees of ignition advance.
I saw a maxium of 4.2 degrees of KR, but this was a spike right in the midde of 2nd on the highway at the begining of a run. I also had a few spikes to 1.7 or 2.3 in begining of runs. The KR would be zero or less than spike for a record or two in the log, than go back down, sometimes all the way to zero.
I actually had my highest spikes under part throttle, although later runs with less, more, or the same throttle produced no KR.
Do you think this might have be false KR? Possibly from dipstick hitting my headers or transmission downshift?
I got a spike when manually shifting the car from 4th, down to 3rd, then 2nd at 60MPH under little to no throttle.
I have read the PCM on the SSEi is much more aggessive on pulling timing, as is the traction control. The TCS will pulling timing even when there is no wheel spin, or its "turned off", if it detects "excessive acceleration".
Does anyone know if this is true, and if TCS would show up as KR on autotap?
Should I get colder plugs?
Would this car be faster with a 3.4 pulley?
Are there any KR mods I should do?
I hooked it up and logged a whole bunch of WOT runs, and some partial throttle, all while out driving around for 30 minutes. This was in 80-90 temperatures with very high humidity. I had 2 other people in the car, plus air the condition on and off through out.
My intake temps ranged from 100-115F.
My car is a 2002 SSEi with 3.25 pulley, Thasher CAI, SLP 1.8 Roller Rockers, TOG Headers, and flexpipe. There is no u-bend. I also had half a tank of Sunoco Ultra 94.
The car currently has stock spark plugs.
I had several WOT runs throughout 1st and 2nd with 0 KR - and 9-11 degrees of ignition advance.
I saw a maxium of 4.2 degrees of KR, but this was a spike right in the midde of 2nd on the highway at the begining of a run. I also had a few spikes to 1.7 or 2.3 in begining of runs. The KR would be zero or less than spike for a record or two in the log, than go back down, sometimes all the way to zero.
I actually had my highest spikes under part throttle, although later runs with less, more, or the same throttle produced no KR.
Do you think this might have be false KR? Possibly from dipstick hitting my headers or transmission downshift?
I got a spike when manually shifting the car from 4th, down to 3rd, then 2nd at 60MPH under little to no throttle.
I have read the PCM on the SSEi is much more aggessive on pulling timing, as is the traction control. The TCS will pulling timing even when there is no wheel spin, or its "turned off", if it detects "excessive acceleration".
Does anyone know if this is true, and if TCS would show up as KR on autotap?
Should I get colder plugs?
Would this car be faster with a 3.4 pulley?
Are there any KR mods I should do?
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I am getting some random numbers as well from the autotap. You can see some of the results in this thread: http://www.bonnevilleclub.com/forum/...pic.php?t=7407 As for the KR I noticed (as shown on the pic in the stated thread) that my KR only showed up after letting off the throttle from full to 0. I'm wondering if this is the PCM sort of engine braking. It would seem consistant with your KR showing up under partial throttle or coming off of WOT.
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What were your 02'* (B1S1 02 Sensor)? The car may be running lean. I need to get more information before I can tell you why you are getting KR.
1 thing you DEFINATELY need to do is insulate your airbox. You are never going to get rid of your KR with air intake temps of 110. You should easily be able to keep them within 5 degrees of ambient temps.
You also need to put in a 180 degree thermostat (preferably drilled) and 1 or 2 step colder spark plugs. If you do this it should get rid of some KR and make the engine run at a more comfortable temperature if nothing else.
It could possibly have been false KR, but I need more information like I said before. What rpms did the kr start at? What rpms did it stop at? Things like that.
If you get me these things I should be able to tell you what is happening:
A list of every single reading you recorded. I need these readings to include:
Vehicle Speed
Engine RPM'*
Throttle Position Angle
Knock Retard
Barometric Pressure
Manifold Absolute Pressure
Long Term Fuel Trim
Short Term Fuel Trim
B1S1 02 Sensor
Injector Pulse Width
Ignition Timing Advance
Engine Coolant Temperature
Transmission Coolant Temperature
Air Fuel Ratio (optional, but helpful)
Air Intake Temperature
Current Gear (optional, but helpful)
Those are the things that I monitor on the GTP at the track, and i recommend monitoring those things every time you do a log. This information tells you basically everything you need to know about how your car is running. If you give me the readings for those things, I can tell you what needs to be changed on your car to get it running properly.
Logging misfires helps too, although I have never done it before, but it can be helpful if you think it isn't running quite right.
1 thing you DEFINATELY need to do is insulate your airbox. You are never going to get rid of your KR with air intake temps of 110. You should easily be able to keep them within 5 degrees of ambient temps.
You also need to put in a 180 degree thermostat (preferably drilled) and 1 or 2 step colder spark plugs. If you do this it should get rid of some KR and make the engine run at a more comfortable temperature if nothing else.
It could possibly have been false KR, but I need more information like I said before. What rpms did the kr start at? What rpms did it stop at? Things like that.
If you get me these things I should be able to tell you what is happening:
A list of every single reading you recorded. I need these readings to include:
Vehicle Speed
Engine RPM'*
Throttle Position Angle
Knock Retard
Barometric Pressure
Manifold Absolute Pressure
Long Term Fuel Trim
Short Term Fuel Trim
B1S1 02 Sensor
Injector Pulse Width
Ignition Timing Advance
Engine Coolant Temperature
Transmission Coolant Temperature
Air Fuel Ratio (optional, but helpful)
Air Intake Temperature
Current Gear (optional, but helpful)
Those are the things that I monitor on the GTP at the track, and i recommend monitoring those things every time you do a log. This information tells you basically everything you need to know about how your car is running. If you give me the readings for those things, I can tell you what needs to be changed on your car to get it running properly.
Logging misfires helps too, although I have never done it before, but it can be helpful if you think it isn't running quite right.
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Originally Posted by dbtk2
What were your 02'* (B1S1 02 Sensor)? The car may be running lean. I need to get more information before I can tell you why you are getting KR.
1 thing you DEFINATELY need to do is insulate your airbox. You are never going to get rid of your KR with air intake temps of 110. You should easily be able to keep them within 5 degrees of ambient temps.
You also need to put in a 180 degree thermostat (preferably drilled) and 1 or 2 step colder spark plugs. If you do this it should get rid of some KR and make the engine run at a more comfortable temperature if nothing else.
It could possibly have been false KR, but I need more information like I said before. What rpms did the kr start at? What rpms did it stop at? Things like that.
If you get me these things I should be able to tell you what is happening:
A list of every single reading you recorded. I need these readings to include:
Vehicle Speed
Engine RPM'*
Throttle Position Angle
Knock Retard
Barometric Pressure
Manifold Absolute Pressure
Long Term Fuel Trim
Short Term Fuel Trim
B1S1 02 Sensor
Injector Pulse Width
Ignition Timing Advance
Engine Coolant Temperature
Transmission Coolant Temperature
Air Fuel Ratio (optional, but helpful)
Air Intake Temperature
Current Gear (optional, but helpful)
Those are the things that I monitor on the GTP at the track, and i recommend monitoring those things every time you do a log. This information tells you basically everything you need to know about how your car is running. If you give me the readings for those things, I can tell you what needs to be changed on your car to get it running properly.
Logging misfires helps too, although I have never done it before, but it can be helpful if you think it isn't running quite right.
1 thing you DEFINATELY need to do is insulate your airbox. You are never going to get rid of your KR with air intake temps of 110. You should easily be able to keep them within 5 degrees of ambient temps.
You also need to put in a 180 degree thermostat (preferably drilled) and 1 or 2 step colder spark plugs. If you do this it should get rid of some KR and make the engine run at a more comfortable temperature if nothing else.
It could possibly have been false KR, but I need more information like I said before. What rpms did the kr start at? What rpms did it stop at? Things like that.
If you get me these things I should be able to tell you what is happening:
A list of every single reading you recorded. I need these readings to include:
Vehicle Speed
Engine RPM'*
Throttle Position Angle
Knock Retard
Barometric Pressure
Manifold Absolute Pressure
Long Term Fuel Trim
Short Term Fuel Trim
B1S1 02 Sensor
Injector Pulse Width
Ignition Timing Advance
Engine Coolant Temperature
Transmission Coolant Temperature
Air Fuel Ratio (optional, but helpful)
Air Intake Temperature
Current Gear (optional, but helpful)
Those are the things that I monitor on the GTP at the track, and i recommend monitoring those things every time you do a log. This information tells you basically everything you need to know about how your car is running. If you give me the readings for those things, I can tell you what needs to be changed on your car to get it running properly.
Logging misfires helps too, although I have never done it before, but it can be helpful if you think it isn't running quite right.
The KR spikes occured at various RPM, in 1st, 2nd, and 3rd gear. I was seeing between 48-52 KP of absolute manifold pressure at WOT, 28-30KP barometric pressure. I believe this translates to 10-11PSI of boost.
The KR would sometimes even go down as the RPM, speed, and boost went up. I would also sometimes have KR with a zero knock sensor count.
The vehical speeds were between 20MPH and 90MPH. I can not go WOT under 20 MPH without spinning my tires.
The air-fuel ratio stayed in the 11-12 range at WOT.
Note even at WOT, the throttle position read 99.6%. Is this right?
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I did another bunch of runs today, mostly at the highway. The temps were in high eighties and low nineties.
I saw similar results, athough intake temp was at 120-130 degrees!
I had one run with had ~4.0 degrees of KR at 86MPH and 5333RPM in 2nd gear - 124 degree intake temps. The car spiked to 4.7, right around as I let off throttle and upshifted. I didn't have simolutanious readings for all parameters right here, so not sure of the 4.7 occured at end of full throttle or at let off.
I did another run and only 2KR at 5506RPM in 2nd and 99.6% throttle, and this was with 133 degree intake temps!!! The manifold pressure was 48KP, so 10PSI boost. My air fuel ratio was 11.9.
Why are my intake temps so high? I am going to take a look at the CAI tonight, and see if maybe its hot air coming up around the enclousure?
I saw similar results, athough intake temp was at 120-130 degrees!
I had one run with had ~4.0 degrees of KR at 86MPH and 5333RPM in 2nd gear - 124 degree intake temps. The car spiked to 4.7, right around as I let off throttle and upshifted. I didn't have simolutanious readings for all parameters right here, so not sure of the 4.7 occured at end of full throttle or at let off.
I did another run and only 2KR at 5506RPM in 2nd and 99.6% throttle, and this was with 133 degree intake temps!!! The manifold pressure was 48KP, so 10PSI boost. My air fuel ratio was 11.9.
Why are my intake temps so high? I am going to take a look at the CAI tonight, and see if maybe its hot air coming up around the enclousure?
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The KR would sometimes even go down as the RPM, speed, and boost went up. I would also sometimes have KR with a zero knock sensor count.
The air-fuel ratio stayed in the 11-12 range at WOT.
Note even at WOT, the throttle position read 99.6%. Is this right?
Why are my intake temps so high? I am going to take a look at the CAI tonight, and see if maybe its hot air coming up around the enclousure?
The car spiked to 4.7, right around as I let off throttle and upshifted. I didn't have simolutanious readings for all parameters right here, so not sure of the 4.7 occured at end of full throttle or at let off.
I had one run with had ~4.0 degrees of KR at 86MPH and 5333RPM in 2nd gear - 124 degree intake temps.
Hope this helps.
Shawn
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This is analysis was really helpful!
So, most of my KR was probably real and due to the the extremely high intake temps, which in turn were do to outside temps and exposed intake.
However, some of this maybe false KR, as indicated by it actually decreasing as boost and rpm increase. The rest may be PCM pulling timing at up shifts.
Overall though, it looks like my car is flowing very well. I am seeing 10-11lbs of boost at WOT and high rpm. Plus even my worse KR, in high temps, with an open intake, is about the same as some people see stock or just with a 3.4 pulley.
Would I be better off with a CAI system like the one from SLP - where it is closed like the stock airbox?
What is the trade-off between the two? Is it more airflow vs colder airflow?
My understanding is the SLP flows enough for a 3.25 pulley, so maybe I should switch over.
Would colder plugs make sense, or will the airbox be enough?
What about the the fact there was KR sometimes with a 0 knock sensor count (i.e. no knock detections)?
I looked at the car tonight and there is a signifcant gap between enclosure for CAI and fender wall, where hot air can get in, plus the enclosure itself is only thin plastic with a metal shield on the bottom.
I also noticed that my engine oil dipstick is right next to one of the collectors on my front header, almost touching it. I couldn't get a good look at tranny dipstick, due to the way the car was parked. I will look at it later.
So, most of my KR was probably real and due to the the extremely high intake temps, which in turn were do to outside temps and exposed intake.
However, some of this maybe false KR, as indicated by it actually decreasing as boost and rpm increase. The rest may be PCM pulling timing at up shifts.
Overall though, it looks like my car is flowing very well. I am seeing 10-11lbs of boost at WOT and high rpm. Plus even my worse KR, in high temps, with an open intake, is about the same as some people see stock or just with a 3.4 pulley.
Would I be better off with a CAI system like the one from SLP - where it is closed like the stock airbox?
What is the trade-off between the two? Is it more airflow vs colder airflow?
My understanding is the SLP flows enough for a 3.25 pulley, so maybe I should switch over.
Would colder plugs make sense, or will the airbox be enough?
What about the the fact there was KR sometimes with a 0 knock sensor count (i.e. no knock detections)?
I looked at the car tonight and there is a signifcant gap between enclosure for CAI and fender wall, where hot air can get in, plus the enclosure itself is only thin plastic with a metal shield on the bottom.
I also noticed that my engine oil dipstick is right next to one of the collectors on my front header, almost touching it. I couldn't get a good look at tranny dipstick, due to the way the car was parked. I will look at it later.
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I went back over my logs again.
On the first run (from home to lunch) my intake temps were right around 110 degrees.
On the second run they started at 150 degrees, drop down to 140, and then down into 130s.
I noticed a lot of times their was no knock sensor count at all when the the KR occured. In fact the only time there were knock sensor counts was right as i let up, and upshifted.
Would this be false knock from the upshift, and maybe PCM pulling timing otherwise when there is no knock count?
On the first run (from home to lunch) my intake temps were right around 110 degrees.
On the second run they started at 150 degrees, drop down to 140, and then down into 130s.
I noticed a lot of times their was no knock sensor count at all when the the KR occured. In fact the only time there were knock sensor counts was right as i let up, and upshifted.
Would this be false knock from the upshift, and maybe PCM pulling timing otherwise when there is no knock count?
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So, most of my KR was probably real and due to the the extremely high intake temps, which in turn were do to outside temps and exposed intake.
However, some of this maybe false KR, as indicated by it actually decreasing as boost and rpm increase. The rest may be PCM pulling timing at up shifts.
However, some of this maybe false KR, as indicated by it actually decreasing as boost and rpm increase. The rest may be PCM pulling timing at up shifts.
Would I be better off with a CAI system like the one from SLP - where it is closed like the stock airbox?
Would colder plugs make sense, or will the airbox be enough?
What about the the fact there was KR sometimes with a 0 knock sensor count (i.e. no knock detections)?
I noticed a lot of times their was no knock sensor count at all when the the KR occured. In fact the only time there were knock sensor counts was right as i let up, and upshifted.
Would this be false knock from the upshift, and maybe PCM pulling timing otherwise when there is no knock count?
Would this be false knock from the upshift, and maybe PCM pulling timing otherwise when there is no knock count?
I hope I didn't forget anything.
Hope this helps.
Shawn
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The insulation idea, is interesting. Would I put this inside the enclosure? Maybe roll a piece and insert in around cone filter?
How does this stay in?
How does this stay in?