HOXXOH Posted November 9, 2011 Share Posted November 9, 2011 With me putting the Callaway Honker, I really hope the MAF doesn't spaz out. I'm throwing on the dyno in a couple minutes. Unfortunately my laptop battery died and I can't log it. My experience says, as long as you leave the airflow alone around where the shroud is up front where your airbridge and filter draw air, you'll be OK. It's when the shroud has been modified or propped open where you get into trouble with air aimed directly into the face of the filter and MAF. People who have used the Vette-Air ram-air units from Carlos had these issues, which required a defuser be placed directly in front on the airfilter to stabilize the airflow. I'm not buying that explanation. The only guy with a diffuser I know, is JoeC5 on CF. The problem is kinda like whistling on a pop top. You can't keep the velocity constant on the filter face. The Donaldson powercore filter will create laminar flow from stagnant air, but can't be expected to deliver constant volume from a turbulent air mass. There are many more than just JoeC5 on CF that had this issue as well.....maybe the LS7 is more sensitive to the issue...don't know. Mark (AirBusPilot) is just one of the guys who also experieinced the issue with the factory OEM setup with a modified shroud and Vette-Air......seems to me Jay417 had issues with the modded shroud as well. I can tell you without doubt that my K&N closed face filter that came as part of my KillerBee II, with the MAF forward design, is WAY more sensitive to the propped shroud, and gives me small issues when at light throttle or coasting with no throttle.Closing up the shroud makes the issue dissappear. This same condition exist if I use my OEM filter and airbridge assembly. It's not just the LS7, as the LS3/LS9 inlets are the same style. It's the way the air flows around the inlet. When the car is on a dyno, the air is stagnant, so the filter ingests air evenly. However, when the car is moving, only the stock system creates a non-turbulent flow around the filter inlet. Notice how the filter is located deep into the frontal cavity and the available air comes from the openings on the lower sides and from the engine bay over the top. That is precisely the location that creates the closest condition to match dead air. Your statement "...air aimed directly into the face of the filter..." was what I was responding to in my reply. Direct air is handled just as well as stagnent or low velocity air. Turbulent air in the vicinity of the inlet creates surging due to fluctuations of static pressure even though the filter may be able to clean up the airflow toward a laminar condition. Filters/CAI that can't create a laminar flow, such as the poor filtering K&N, either excerbate the problem or cure it through a more controlled inlet found on systems like the Vararam. The Vette-Air system that doesn't control the air completely from the inlet to the filter contributes to turbulent air rather than resolve the issue. Link to comment Share on other sites More sharing options...
Jon Posted November 9, 2011 Author Share Posted November 9, 2011 I my drive home last night I felt some surging. I'm going to disconnect the battery to reset the pcm(power control module), which is what controls the engine. I will also log on the way to work tonight. Link to comment Share on other sites More sharing options...
Two Fangs Posted November 9, 2011 Share Posted November 9, 2011 I'm still trying to figure out these technical terms like: "And you though TRON was trippy" "this pisses off the computer a tad" "...the MAF freaks out" "hope the MAF doesn't spaz out" "all kinds of crazy shit starts to happen." And who are Jeanne Dixon and TJWong? Yeah, guilty. I traditionally relate conditions caused by erratic voltage signals or outputs in a way that is related to emotions or actions. I find that these are more easily related to than long drawn out explanations of non-perfunctory voltage signals. As far as TJWong, he is a reputable tuner on the upper West Coast. And Jeanne Dixon? Well, she is a psychic. Link to comment Share on other sites More sharing options...
Jon Posted November 10, 2011 Author Share Posted November 10, 2011 Well I did some logging on my way to get food for the family tonight. Didn't matter what gear I was in, if I floored it I got 3-6* or burst knock. I also did some long pulls on a highway down in Mexico and got what I think was real knock. If some of you guys want to PM me your email address, I will send you my log files. I can't post them in here. Link to comment Share on other sites More sharing options...
Two Fangs Posted November 10, 2011 Share Posted November 10, 2011 Well I did some logging on my way to get food for the family tonight. Didn't matter what gear I was in, if I floored it I got 3-6* or burst knock. I also did some long pulls on a highway down in Mexico and got what I think was real knock. If some of you guys want to PM me your email address, I will send you my log files. I can't post them in here. Send them to ********** at aol dot com. Link to comment Share on other sites More sharing options...
Jon Posted November 10, 2011 Author Share Posted November 10, 2011 Are you the Goddess of Healing??? Link to comment Share on other sites More sharing options...
Two Fangs Posted November 10, 2011 Share Posted November 10, 2011 Are you the Goddess of Healing??? 151 is Link to comment Share on other sites More sharing options...
Jon Posted November 10, 2011 Author Share Posted November 10, 2011 Lol. True. I'll email you my log files when I get home from work in the morning. Link to comment Share on other sites More sharing options...
Two Fangs Posted November 10, 2011 Share Posted November 10, 2011 Sounds great. I am off Friday. My morning is a little full, but I should have some time to take a good look at them. Link to comment Share on other sites More sharing options...
Jon Posted November 10, 2011 Author Share Posted November 10, 2011 No worries. It's so hard to not tune my car. I had burst knock turned off on my GTO. Link to comment Share on other sites More sharing options...
NicD Posted November 10, 2011 Share Posted November 10, 2011 The other thing is that some of the later calibrations will show total knock retard as the regular KR pid meaning you will see a static amount of knock retard while in throttle depending on IAT, ECT, and any other table that can add/remove timing from the main timing table. You will want to log all timing pids so to speak so you can see which tables are pulling timing all the time. Also report back with the version of HPT that you are using, some of the later betas may have gotten rid of this as I haven't seen it for a while. Link to comment Share on other sites More sharing options...
Jon Posted November 10, 2011 Author Share Posted November 10, 2011 I'll shoot you an email tomorrow as well Nic. I'm using that modified log file that you gave me. The weird thing is that I couldn't see STFT and LTFT on the histograms. Link to comment Share on other sites More sharing options...
Two Fangs Posted November 10, 2011 Share Posted November 10, 2011 Are you using 2.23.xxx? Link to comment Share on other sites More sharing options...
Jon Posted November 10, 2011 Author Share Posted November 10, 2011 I can't remember. It's a beta I downloaded a couple months ago. Link to comment Share on other sites More sharing options...
Two Fangs Posted November 10, 2011 Share Posted November 10, 2011 Yeah, if you are using a beta you are using some version of 2.23 Link to comment Share on other sites More sharing options...
NicD Posted November 10, 2011 Share Posted November 10, 2011 I'll shoot you an email tomorrow as well Nic. I'm using that modified log file that you gave me. The weird thing is that I couldn't see STFT and LTFT on the histograms. You probably have to remove and re-add the histogram functions for those as that definition I sent you is generic and the later calibrations have different boundaries. Link to comment Share on other sites More sharing options...
Jon Posted November 10, 2011 Author Share Posted November 10, 2011 Email sent to both of ya. Link to comment Share on other sites More sharing options...
NicD Posted November 10, 2011 Share Posted November 10, 2011 Just scanned through the first one pretty quickly and I see the normal burst knock at tip in on all the wide open throttle hits with some mild KR but that's pretty typical as the newer vehicles just ride that line so to speak and heavily depend on the knock sensors to save their ass. The good thing is that with only a 2-3 kpa drop at WOT to redline the intake is doing it's job and it's pretty efficient. I've seen a lot worse up to 7 kpa drops which really hurts the numbers. All in all I don't see anything bad and with your minimal mods it's doing great backing up your dyno numbers. Your fuel trims are not that far off either so the intake does a good job replicating the factory cross section and airflow model where the MAF is. I would probably add the burst knock pid to the scanner to clarify some of the timing hits but it sure looks like it and it's normal and not a bad thing. Is there something you saw in the logs in particular that you had a question on? If you do post up the location in the log in time scale. Link to comment Share on other sites More sharing options...
Jon Posted November 10, 2011 Author Share Posted November 10, 2011 Nothing specific. How much am I leaving on the table staying with the stock tune? I hate burst knock. It's not even real knock. Argh! Link to comment Share on other sites More sharing options...
NicD Posted November 10, 2011 Share Posted November 10, 2011 Nothing specific. How much am I leaving on the table staying with the stock tune? I hate burst knock. It's not even real knock. Argh! The burst knock is there for a reason on a stock setup and it's not harmful, besides it's minimal at only a couple of degrees and hardly has any effect on performance. Normally it's not really necessary to remove it except for larger cammed cars, speed density, etc. With your minimal mods you aren't leaving much on the table except for leaning it out a bit but that's not going to do much since the LS3/L92 cars like to be on the richer side at WOT anyways. Link to comment Share on other sites More sharing options...
Two Fangs Posted November 11, 2011 Share Posted November 11, 2011 ^^^This is the truth. Nothing wrong with the tune, I see a few things I would change looking at the stock cal, but Nic is right, LS3s do a little better on the fat side, and traditionally do not require a fuk-ton of timing to make power. If you are truly concerned about real knock, log the burst knock PID and compare it to the recorded KR. Link to comment Share on other sites More sharing options...
Jon Posted November 11, 2011 Author Share Posted November 11, 2011 I might need to hit you guys up later to get my logging histograms configured correctly. I'm a total newb to this stuff. Link to comment Share on other sites More sharing options...
Two Fangs Posted November 11, 2011 Share Posted November 11, 2011 I am sure one of us will be available. Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now