Learning to tune my car for Autocross and NHA HillClimbs

[gmtech16450yz]

Ok since it looks like nobody else went back and read my Optimum Spark thread to see what it said 3 years ago, I'll copy and paste the first section here...

Ok guys, here you go...

Optimum Spark tables. Absolutely the most misunderstood and neglected tables in the E69. I'm here to say these tables (along with many other obviously) are VERY POWERFUL when you figure out what they do and how they work.

I waited over a year for somebody else to figure these tables out, but to this date I've never seen ANYONE else using these tables for tuning. I actually don't quite understand it, we all begged and pleaded to Chris and Bill to give us more for the LNF E69, then when they do, tables like these are left gathering dust.

Here's basically what these tables can do-

Ign timing control at idle, where so many guys have had issues that they couldn't fix.

Ign timing control on cold starts, again this will fix all "Cat Warmup Delete" surging idle issues if you figure out how to use them. I'll post up a log of a perfect cold start and idle that my car has had for over a year on the stock and EFR turbos, straight gas and E47.

Ign timing control to eliminate the timing drop(s) that occur right before 3k and 4k rpms. Tune these tables right and the ign timing drop of 10 or 15 degrees will be GONE. No more dips in those dyno charts that pretty much every LNF dyno that starts the pull at 2k or so has. ( When I was trying to decide which vendor to go with on my EFR build, one of the vendors I didn't go with really wanted me to fix this for them. Unfortunately, I never did tell them how to do it.)

Ign timing control on decel.

Throttle control at all rpm's and loads. (Really.)

Boost control at all rpm's and loads. (Yep.)

What else am I forgetting? Not sure.

Here's a very short version of how these tables work. They're lookup/compare tables. That means they don't directly control anything, they're tables the ECM looks at and compares what it's seeing elsewhere to the numbers in these cells. For instance, if you have 20 degrees of ign timing in a certain cell, but the stock number was 2 degrees, the ECM will do this- (ECM talking here- lol) Ok, the main ign timing cell I'm in right now is requesting 20 degrees, but my Optimum Spark cell is saying something like 5 degrees in that same cell. So if my airflow says I'm making plenty of power (again, more lookup tables involved), and my Optimum Spark cell says I'll be making optimum power at 2 degrees, why do I need to go all the way to 20 degrees? I don't, I'm gonna run this cell at say, 5 degrees.

Here's what happens in another similar situation- That particular main timing table cell was at 20 degrees stock, but you've set it to 2 degrees in your tune. That particular cell in the Optimum Spark table is at 30 degrees. Again, here's the ECM talking...
Ok, I'm not making the power (or airflow) that's being requested of me, so I'm gonna look at my tables to see what I can change. Optimum Spark cell says I'd be making optimum power at 30 degrees in this situation. My main ign table is requesting 2 degrees, there's no way I can make the power that's being requested at that amount of timing, so I'm gonna bump that up to say, 12 degrees. (Again, lot's more tables we can't see that control the amount of range any table can have. There IS a limit to how much timing the Optimum Spark tables can control. When they get over that limit, they use throttle and boost to control airflow/power.) Back to the ECM talking- Ok, so if I'm still not making enough power at 12 degrees ign timing, I'm gonna have to open the throttle more or give it more boost.

End result- you're NOT getting the requested 20 degrees that you put in your ign timing tables, and you're also NOT getting the requested airflow that you asked for in your DAL's, MALT or other airflow tables. Starting to see how powerful these tables are? Notice how these tables are in the "Torque Management" area instead of the "Spark" area? That's because they control torque more than they control spark directly. Lookup tables in any ECM are EXTREMELY powerful.

Here's a very simple analogy... The sky is blue. You're in charge of keeping the sky blue. Your "lookup table" says it's supposed to be blue. Somebody else made the sky blue, not you, that's another "table". You walk outside everyday and the sky is blue, everything's cool. You walk outside one day and the sky is green. You look at your "lookup table", it says it's supposed to be blue. Somebody changed that other guy's "table" to make the sky green. Your table says it's supposed to be blue or bad things are gonna happen, so you tell the other guy "Hey, I need that sky to be blue or we're gonna be in trouble!" He says "Ok, but this guy told me to make it green, so how about a compromise, we'll make it kinda blueish/green, Ok?" lol. Make sense? The problem is nobody got what they wanted. The sky is not green like the table was changed to, and it's not blue like the other guy thinks it should be. So now they fight over what color it's gonna be and nobody's ever happy.

That's the way these computers work. You can make changes, but you better make sure what you're doing is making all the other hundred tables happy. Otherwise they're all gonna fight each other and the car is gonna run like cr@p. As you can see, there are HUNDREDS of tables interacting with each other on these E69's. Anyone that says "tuning the LNF is easy" and "there's only a couple tables that everyone uses" is ignorant. Even I don't know all the table interactions on these E69's. Nobody does. Like I said, if your tuner says he's got it all figured out, RUN AWAY FROM HIM. I can guaranty he doesn't understand all there is to know about these four little tables. I've seen dozens of tunes from every vendor and professional tuner, I've NEVER seen a tune with modifications done to these tables.

Seriously. You put the wrong values in and here's what it can do- start and run perfectly at idle, run fine around town, but give it full throttle and IT WILL STAY AT FULL THROTTLE. Remember, the tables say "Optimum Spark", but they have a huge effect on throttle and boost also. BE CAREFUL! I can't stress this enough. These tables are powerful, way more powerful than the DAL table by far. You can make it so the throttle plate goes wide open at 1/8th pedal position if you want. You can make the turbo boost when you let off the throttle. You can make the throttle "latch", like I said above, it will not decel after you go past a certain pedal percentage. Basically, you could die!

lol. I forgot about my "Blue Sky, Green Sky" analogy! I love analogies! I've honestly forgotten half the stuff I learned back then because I rarely work on LNF's anymore, but it looks like it's still valid info. Yes, the Optimum Spark tables control airflow and boost, just like I remembered. Get them wrong and you can end up with -.5 degrees ign timing, 29.5psi boost and not be in PE. Again, I never looked at his recent tunes so I have no idea if that's what the cause is. I do know what the symptoms are by looking at the log. Hey, here's another good analogy that just popped into my head about looking at logs vs. looking at the tune...

A guy has a heart attack. He's in the ER. What does the doctor do? Does he do a DNA test on the guy to find out what his genetic makeup is? No. Does he ask him where his mother and father were born? No. Does he do a blood test to see what his blood type is? No. Does he ask if he's married or has kids? No, although that might explain the heart attack. These are kind of like the guy's "tune", it's what parameters he's been setup with. It's important stuff, but it's not going to tell the doctor what's wrong with the guy.

So what does the doctor do? He hooks up a bunch of wires to the guy, opens up his HPTuners Human Scanner or something like that and "scans" him. He can NOW see exactly how that guy is "running". What does he see? He sees a problem with the graph of the electrical signal from his heart. Maybe his commanded heart rate isn't matching his actual heart rate, hell I don't know. I know that doctor is doing pretty much what we do, trying to figure out what's wrong with the way this guy is operating. "Scanning" him will tell him that. THEN he can try to make changes to his "tune" to get the scans to look the way he knows they should.

I made that last part stand out because that's the key. If you don't know what the scans are supposed to look like, or what you're supposed to be looking at, you're screwed. I guess my whole point here is I think some of you need to concentrate less on what's in the tunes and more on what's in the scanner readings. The scans can tell you what's in the tune. The tune can't tell you what's going to be in the scans. There! Put that one in the "Gospel According to John"! Hahahahahaha By that I mean the scan can absolutely tell you what the tune needs more or less of. You can make educated guesses as to how to set up a tune, but you'll never actually know how it's going to make any particular car run until you put it in and scan it. Especially on the LNF's.

[gmtech16450yz]

John you are right and wrong. Right in the sense that yes people need to change the tune to help fix the scans. What if there is a mechanical problem? This is an unrealistic analogy but we'll say the turbo isn't pushing what it is supposed to. In the tune we command something but we see less. So we up it more and we make it push the 23psi. Everything in the log looks great. Down the road the owner is working on his car and sees that a hose is cracked. He fixes the hose. Now he is over boosting. Was it smart to fix the log with the tune when it wasn't the tunexpected causing the issue to begin with? I had a guy pushing less boost because a solenoid was bad. I could have added more but it would have been wrong. You hold a valid point though.

The fact is it is a completely different tune with the exact same issue from what I can tell (what people are saying, I have not looked at a tune or log). This would make me believe mechanical issue though I could be wrong.

That's where I look at things a little differently. (I'm gonna try to make my point here in as respectful as a way I can. It might not come across that way so please don't take it the wrong way.) Your "fact", and therefore your diagnosis is based on opinion, or really, emotion. You're still also basing much of your diagnosis (whether you realize or admit it or not) on Term's reputation. You really don't want it to be "his fault". I can appreciate that and understand that. But that shouldn't be part of a conclusion. Again, that's letting emotion into the diagnosis. When I'm gathering information to make a diagnosis or come to a conclusion, I put almost no weight whatsoever on things like reputations or "what people are saying". Those are not facts, those are opinions and random thoughts or statements. I base my conclusion on the actual facts, like comparing the log from the blown engine to the log of the new engine. To me, they are NOTHING alike. I'm also going to assume, since I did not compare the tunes, that they are also very different. I can't claim that as a fact, that's an educated guess.

So for me, "what people are saying" doesn't qualify as a viable piece to the puzzle. The ONLY pieces of the puzzle I looked at were the two logs, the before and after. They are different. They are BOTH bad looking logs. Those are facts. Wanting to believe that whoever created both of the tunes behind the two logs as being a competent tuner and not in any way at fault is of course noble and nice, but it should be given NO weight in the process of drawing a conclusion.

Oh and I just thought of an analogy to your analogy! lol.

Your analogy of the boost leak is perfectly reasonable. Of course you can't tune away mechanical problems. Here's my addendum to my "guy in the ER that had a heart attack"...

So when the guy had the heart attack, he fell on a knife and stabbed himself in the belly. He's now bleeding profusely. What does the doctor do? Hook up his "scanner"? NO! He fixes the hole in the guy's belly first! After he fixes the belly wound, THEN he can hook up his scanner and see how the heart is doing. Trying to diagnose a heart problem with blood gushing out of the belly is retarded! lol. How's that?

[gmtech16450yz]

Ok here's the log I posted in the other thread from before he blew the engine. Compare it to the one I just posted of him driving with a different tune and a rebuilt engine. Totally different logs, therefore totally different tunes. Look at the spot in the pre-blown engine log that I circled white. That's pedal vs. throttle. It's over 50%, it looks like about 65% pedal and throttle. Now compare that to the new tune log. Same or different? The part of the tune that controls pedal to throttle was actually BETTER in the pre-blown log. The logs are different. The tunes are different. They're both not very happy looking.


Log from before engine was blown...




Log from after engine was blown...





Now look at that spot I circled and look at the mixtures. It's at commanded 1.00 and actual 1.00. It's not in PE. It's at ~65% pedal and throttle, and about 15psi of boost, but it's not in PE. That's a problem with the tune. I'm betting the PE table is at stoich in all but the last or last two columns. The LOG is telling me the PE settings in the tune are wrong. Pedal to throttle is ok, boost is ok, but it's not in PE. In the log from after the engine work, the pedal vs. throttle is WAY different. It's again not in PE, but this time it's because the driver was only demanding 30% with his foot but the tune decided it needed 77% at the throttle. Does this make sense to you guys? Am I explaining it well enough? The logs are different and the tunes are different. They BOTH have issues. I'm not even addressing any possible mechanical problems because that's data I don't have. I can only assess the data that is available to me, and that goes for everyone else too.

[codename Bil Doe]

I'll keep this brief for now because I should be asleep. The tune after the engine is fine. How do I know? Because it's my tune that I offered to tbsteck for free because I felt bad for him getting screwed by term2. How do I know the tune is good? Because after several hundred logs, DAILY DRIVING IT AND ROAD RACING IT THE TUNE WORKS FINE. This is where posting a screen shot from a log and saying look it's the tune again is completely incorrect and irresponsible.

The tune isn't a soft mild tune. It's designed for racing. IT CAN AND HAS BEEN ALSO DAILY DRIVEN FOR OVER A YEAR. The pedal is very linear. How is that possible?

1) throttle blade following pedal position is no indicative of driveability or control. It's 2009 era tuning thinking the tb has to follow the pedal. There are multiple tables working in conjunction to develop the overal result of engine power.

2) it has an aggressive OS BECAUSE IT'S A RACE TUNE. Guess what? It's very streetable and drives like it has 50hp below 23% pedal. How could I know the threshold point for tb not following pedal position is 23%? From hours of testing and analysis.

3) You can be boosting and still be holding a steady speed. Not possible! Actually, it is. There are many factors that go into increasing power. Thia was extremely important for road racing because you need linear pedal control coming out of a corner. Originally, I tuned it like an on/off switch. it was undrivable on a road course. Guess what? That magical 23% pedal region. The OS is a single value and works in conjunction with a linear DAL and other tables to give a linear pedal down low rather than the typical exponential response.

Sorry to be blunt, but making judgement calls while ignoring the other evidence in the screenshot you posted is not responsible.

I'll tell you exactly what the tune does. 22.7psi flat, 5.6ms inj timing, 2100-2200psi rail pressure as low as 7psi (obviously ramped up), .87 lambda, steady timing.

I'm getting off the forums for this exact reason like Mike is. Not a mention of the ridiculously low rail pressure or the crackhead timing that looks more like a seismometer. It's out of control jumping all over the place.

There's something seriously wrong, probably mechanically. Could be something simple like a hose to the wg. It might be an issue with the copy/paste tune flashed, it may be ecu, idk. I'm not there looking at the car to inspect it.

How do I know the logs don't look like that with the tune I sent him? Besides the hundreds of on track and street logs I've taken, I just had both cars out this weekend.

I really respect your inout and work. But, instead of posting inflammatory comments with no basis, why not try getting more information first and helping tbsteck figure out what's wrong?

That's exactly why I told him to flash the stock tune and post a log.

I think that was brief enough. Good luck and hope people tuning LNF's read ALL the threads explaining how the tables work in conjunction with each other.

Next people will be bringing up the pill mod as a good idea again.

[cobaltssoverbooster]

Now I purposely stopped tuning and trying comment on new information because I do not have any LNF/LDK/LHU projects to test new stuff out. To prevent handing out bad data I am strictly trying to only help people get comfortable with using the software before they get started tuning. I only post this opinion now because I feel that what I am seeing in your logs is extremely dangerous events. If my findings come out rude please excuse me, I mean to highlight them so they can be accounted for, reviewed, and corrected which enhances your learning.

Now TBSteck you hit the ground running by flashing a non factory tune file into your fresh and expensive motor. How do I know? simple, even the gmpp file doesn't have as vicious of a boost and tps offset as what I can see in your logs now. the factory file is safe enough to make motors last 100k miles bone stock, it would break your new motor in just fine while you figured out how to use the vcm scanner properly. I have never broken a motor in on a modified file, I always use a original factory file and at the most only modify the map sensor data for those setups that have 3 bar conversions. In this thread i see a lot of data scans and no editor file. Can we see the tune file that is causing all the problems in these log files please? If you would have posted a file we could have told you in the first post if your tune was going to be a good one to start with but all we got here were logs of an unknown file being ran 8 posts into this thread, so as far as entering values goes, we never had a chance to tell you if the file was in the ball park for a good starting tune.

now im only going to mention one log file out of the many I sorted through.
log file: 2015 05 29 maf 3b

Why are you not recording intake and exhaust cam desired positions? the primary table still has room and the data is important. this can help track commanding problems as the cams are one of the hardest control systems to force the ecu to command the actual requested value. it is one of the many indicators I use to keep track of how well I am controlling the ecu.

I saw a lot of etc and etc pedal offset going on in there. some ranging in the 30-40% offset range. 4% throttle and 25% etc plate was a great example. sneeze on the throttle constitutes 25 to 30% opening on the tb? um..no.

The whole tune file the commanded kpa value is offset from the actual kpa.

@ 2.21.594 you already hit 23psi with roughly 31% throttle in a state that shows your in slow acceleration which shouldn't require boost at all. commanded lambda is 1.0 since pe is remaining inactive, actual afr 1.0 with lean fluctuations as the maf is not probably not finished. actual load is 200% at 3000 rpm. 200% load at 31% throttle holly frijoles!!

@ 2.13.907 fuel pressure is low in the 1200 psi range, injector ms 7.6. Full boost at 3k rpm with only 32 % throttle and 70% tb opening. pe still not kicked in. You haven't even hit power enrichment and your damn near out of the injectors range of reasonable operation. granted you have more time to fire at lower rpm before the next cycle comes around but damn that's excessive. AS noted before 38% throttle offset and only 30% away from having the throttle plate wide open with your foot only 1/3 the way down on an acceleration event not a deceleration event.

@4.42.469 boost desired in the 140 kpa range but actual overshoot is well into the 200 kpa range. Controllable with turbocharger settings and opti spark controls.
@13.04.985 14 psi overboost on part throttle acceleration 25% etc pedal position. guess what..lambda still 1.00 @ 23.8 psi

The overshoots im catching are killing you since they are all occurring when pe is no where near activating and if it is in an activation range it never passed the load and rpm selection that would push pe out of a 1.0 lambda control and into a richer state keeping that high boost level safe. Now I only tore up one log file but it alone is proof that your new parts are on their way to being caught by your oil pan. It would behoove you put a bone stock gm file in and focus on the basics highlighted by GMT and MikeM.

John, if you don't mind, in your screen shot above how did you arrive at 29 psi? Highest boost lo res I saw was roughly 262 kpa which would be high 23 psi. boost lo res at idle is 98 kpa so with the sensor correction leaves that 164 kpa/23.78 psi. everything else I get the same as yours just wondering why I have something different than you for boost.

[gmtech16450yz]

I am in awe right now. I'm skipping breakfast and I'm going to be late for work but I absolutely have to respond to the last few posts here.

I am so proud and humbled to be a part of this tiny section of the internet forum world. Seriously. You all know I talk chit about how weird the Solstice/Sky people are. I've been banned from 2 of the 3 Kappa forums. I'm holding out hope for the Sky forum simply because I really want the forum for the car I'll always have to be a good place to hang out. It's doubtful it will ever be that, but that's another story. It's not because I didn't try, that's why I was banned from the other two, because I tried too hard to help and protect others. I failed there.

But this forum and this little 4cyl section has always been different. The last posts here prove that. TBSteck (Tyler? Sorry, I forgot), do you have any idea what you have here in this forum? You have something that NO other forum I've ever seen has. You have a group of very intelligent guys that are willing to stay up all night in an effort to help you, a total stranger. I hope you realize how lucky you are, this just doesn't happen very often in the forum world.

I was afraid that my well-meaning post was going to be taken the wrong way. I was afraid this was going to turn ugly, like SOOOOO many forum threads seem to do, not here but in other forums. This forum, and you members in here specifically didn't let that happen. THAT'S why I'm proud and humbled. I'm proud because I feel I was a tiny little part of the "Learn and Share" philosophy here years ago. But it didn't die with me, it flourished. I'm humbled because I'm in the presence of GOOD people that care. I'm humbled because I'm in the presence of people that aren't afraid to stand up and voice their opinion. I'm humbled because I'm in the presence of people trying to do the right thing. This world needs more of this, it most definitely doesn't have enough. This is a community trying to protect one of it's members. And that's not a small statement. We all have our own lives and problems. Look at the length of the posts above. That takes time. That takes effort and passion and a willingness to give back what you've learned to others even if you have to lose sleep to do it. I am absolutely blown away, and that doesn't happen very often.

Bill, CSSOB, Mike and others- DON'T GIVE UP AND LEAVE. Please. You ALL have knowledge and passion to share. Guys like TBSteck NEED it. You all have the ability to make this forum better, or actually, amazing. Bill, you talk about the Gen 5 guys not knowing what they're doing. HELP THEM. Post links to our threads that are relevant to that ECM also. Mike, teach the guys here something huge in your other thread that happened to have NOTHING to do with the whole reason you made that thread. That happens sometimes, I've done it myself. If you feel like you failed (sorry, that's too strong of a word) in that thread, you didn't. There's an opportunity for learning there, it just needs to be cultivated. CSSOB, THANK YOU from the bottom of my heart. I know how much time making that post took you. You guys are ALL amazing. Keep being amazing and maybe this little corner of the internet will still be the cool place to hang out it's always been.

[mkriebs]

I had a response all typed and I erased it. I know what the issue is with these logs. People keep saying we're not reading, which is false. You don't KNOW if we read, you only know if we respond. I have read damn near everything in this forum relating to the LNF, but my car is sitting without an intake manifold or turbo right now, so I can't try anything out. Unfortunately, much of what I have learned in recent history is at the misfortune of the OP.

I don't know what to say. I know what the problems are, but I can say this...

I think the OP needs to start with a fresh, OEM tune (modified for 3 BAR MAP if that's what he has). The reason I say this is, we have a bunch of smart tuners here. A lot of the GDI pioneers, IMO. But everyone has their own thoughts on how the OP should proceed.

So, my final recommendation is to start with a clean OEM tune (adjust for GMPP MAP sensors, if need be). Work on the MAF tuning FIRST. A skewed MAF will schmuck everything else up. Get your STFT to -5/+5 (preferably less). Then work on the PE tables (.88 lambda seems the safe consensus). Then work on boost (24 psi being the max for the KO4, a flat line if on OEM MAP sensors generally means much higher than the 22.5 psi the scanner will show). While working on boost, keep an eye on fueling and making sure of two things: lambda is correlating to commanded lambda with very little % error, fuel pressure and commanded fuel pressure are correlating with a very small % error. Once the MAF, boost, and Fuel are done, move on to timing. Timing will consider all of the tables, Main Spark and Optimum Spark.

The other stuff I want to write, I will not, as it is neither pertinent nor constructive to this thread.

[gmtech16450yz]

I had a response all typed and I erased it. I know what the issue is with these logs. People keep saying we're not reading, which is false. You don't KNOW if we read, you only know if we respond. I have read damn near everything in this forum relating to the LNF, but my car is sitting without an intake manifold or turbo right now, so I can't try anything out. Unfortunately, much of what I have learned in recent history is at the misfortune of the OP.

I don't know what to say. I know what the problems are, but I can say this...

I think the OP needs to start with a fresh, OEM tune (modified for 3 BAR MAP if that's what he has). The reason I say this is, we have a bunch of smart tuners here. A lot of the GDI pioneers, IMO. But everyone has their own thoughts on how the OP should proceed.

So, my final recommendation is to start with a clean OEM tune (adjust for GMPP MAP sensors, if need be). Work on the MAF tuning FIRST. A skewed MAF will schmuck everything else up. Get your STFT to -5/+5 (preferably less). Then work on the PE tables (.88 lambda seems the safe consensus). Then work on boost (24 psi being the max for the KO4, a flat line if on OEM MAP sensors generally means much higher than the 22.5 psi the scanner will show). While working on boost, keep an eye on fueling and making sure of two things: lambda is correlating to commanded lambda with very little % error, fuel pressure and commanded fuel pressure are correlating with a very small % error. Once the MAF, boost, and Fuel are done, move on to timing. Timing will consider all of the tables, Main Spark and Optimum Spark.

The other stuff I want to write, I will not, as it is neither pertinent nor constructive to this thread.

Thanks for omitting the non-constructive stuff Matt, I appreciate it. If it's about me, I've heard it all before anyway! lol. I have strong opinions and passions and I realize not everyone gets the point of or appreciates my candor. That's certainly not what this is about. This isn't personal on any of our parts, this is a bunch of strong willed adults sharing opinions and thoughts. That's awesome in my book.

Anyway, I put one thing you said in bold because I think that's the one thing most of us ARE all agreeing with. I'll even put your recommendations in red so they can be read. (hahaha) I would only add ONE thing to your approach, and even that has already been said by others. I would DRASTICALLY drop the boost. Hell, cut all the boost control tables in half or half again. Get that engine running well on a max of 15psi before going any further. CSSOB mentioned that he "hit the ground running" on his tune. I totally agree. That's not how to start out a tune, especially on new engine parts. Take baby steps. That's the biggest mistake Term2 made in my opinion. Boost on a turbo engine is not something you can say "just put these numbers in your boost tables and your boost will be xx.xx. It doesn't work that way. The ONLY way to get control of boost is to start out WAY low and work up.

Thanks Matt.

[codename Bil Doe]

This bothered me so much last nite that I was going to post a bunch of screenshots demonstrating what I meant. But, I'm not even going to bother. I'll leave you with this-

You could set your optimum spark table to all 20's and still not hit 5psi of boost by 6500rpm. How is that possible? Because not one mention has been made of PID's, either. Derivative gain will overpower OS. Integral gain if adjusted too high will make the tb slam shut faster than you can jerk your foot off the pedal. Understanding how the ENTIRE tune works together gives you the whole picture, not just understanding one or two tables.

[gmtech16450yz]

I don't actually fully agree to that approach. Also just because you held stuff back doesn't mean you didn't feel obligated to say anything. You're right I don't know because I haven't looked at anything since Terms tune and logs. Why? Because of smart remarks like that and improper tuning from people who don't know or just feed off of what everyone says. I'm sorry this is coming across rude but this is the reason I am done.

I will give you one reason why I don't agree with your approach overall. Tuning the MAF and then everything else can skew the MAF a lot. All of the other tables you are talking about affect fueling. You will end up changing MAF values again. Do you know what happens when you skew the MAF off too much?

Last bit of advice, I already said it, start with a stock tune and see if you have these same issues.

Sorry for coming across like a d*ck.

I think it's assumed by anyone that's ever tuned a car that you don't adjust one part of the tune and then never go back. Obviously you don't follow those steps one by one and then you're done. I doubt that's what Matt meant. Every table effects every other table. That's been true since the internal combustion engine was made. You don't adjust the idle mixture on your Model T, then advance the timing and not expect to have to go back and tweak the idle again. Oh and in case you young'ins didn't know, you adjusted mixtures, ign timing and idle speeds right on the steering. Anyone that drove a Model T or Model A HAD to understand how to adjust mixtures, ign timing and idle speeds. Funny how things really go full circle huh? In the 1920's they had closed loop fuel and timing control. The only difference was the driver was an active part of the loop!

[mkriebs]

John, you're right. I skipped over that part about starting at low boost because I thought it was common sense. BUT, I think I would prefer to fully tune boost before moving on to timing. Just the way I have always done it. I can dial the boost to get the numbers I want, then I can dial the timing to the levels that seem appropriate and safe for those boost levels. But you say start low and work up, which is a nugget of golden advice.

Mike, I take no offense to anything on the internet unless it's a comment about my mother. I do agree that tuning the MAF first can lead it to be skewed again, but where would you start? Instead of saying you don't agree, please state what you would recommend. I guess tuning is like buffing a car. You get the nitty gritty big stuff (buffing) out of the way, but it would be incomplete without wax afterward, therefore, tuning the MAF, focusing on other things, then going back over it with a coat of wax (fine tuning loose ends) would be a wise way to go about it. Just my method.

Bill, you just dropped a gold nugget of advice... "Derivative gain will overpower OS. Integral gain if adjusted too high will make the tb slam shut faster than you can jerk your foot off the pedal." I don't think I knew that derivative gain would overpower OS. Might have read that somewhere, but there is such a massive amount of info on this site sometimes thoughts get pushed to the dark corners of my brain.

I am sorry so many people seem to be onboard the mass exodus. It's really tragic.

[cobaltssoverbooster]

Tune everything that affects cylinder pressure first then move to timing as it shifts the cylinder pressure spike. Every motor has a different pressure amplitude and that is what determine es where the timing may lie. I mean that in the most basic of descriptions.

[TBSteck]

DUDE! STOP DRIVING IT!!!!! NOW!!!


Sorry to yell but WTF is going on with your choice of "Tuners"????? Look at this screenshot. 29.5psi boost, your foot is at 32% but the throttle is at 77%, and because of that, you're not even in PE so your Lambda is 1.00!!! Holy crap dude you need to start over with a new tuner and a STOCK LNF file for that car. Do what Bill said to do, cut the boost tables IN HALF or more. DO NOT run ANYTHING over 20psi boost before you get a handle on the rest of that tune. Hell I'd have that boost maxing out at 15psi until I knew I had control over the rest of the engine management. You're driving a car with a new engine and NO CONTROL WHATSOEVER of the engine management.

Again, sorry to yell but WTF? I've stayed away from these couple LNF threads because they kept going in a wrong direction, but geez, after taking a quick look at your log I knew I HAD to say something. I don't know who's helping or not helping you, but my advice is to start over. Drop boost dramatically until you figure this other stuff out. Forged pistons are great, but that engine isn't gonna take a second round of this kind of abuse.

Oh yeah... and 1,271psi commanded fuel pressure at 29.5psi boost?????? The injectors are at 7.3msec at 3800rpm, at 6800rpm they'd probably be twice what they should be. Faaaaakkkk.

Sorry I didn't respond sooner but we had a autocross event this weekend and being Chief of Timing I am there both days from setup at 7 a.m. to tear down which was around 7:30ish on Sunday evening. ...

Now to respond on what gmtech16450yz is pointing out on the boost levels. Oh how do I say this ... (please I do not want to hurt anyone feelings because I want your help but ..) Note: The blue color is so you can tell my previous posts from the ones in this post, no other meaning.

On my very first post (#1) on this thread I said "Because of my previous experience I am extremely gun shy and I want to make sure I start out right and then I want to continue to make adjustments until I feel it is street ready and then I want to get it race ready.

My logs look a little bit odd when it shows 1.9 - 2.1 boost level idling but when you look at the dash display it show nothing (blank is 0). That is suggesting to me maybe my log .cnf files aren't right. I downloaded gmtech16450z .cfg and VCM Editor.cfg files and am using those files. I haven't change out the VCM Scanner.cfg (it wasn't available in the forum I could find), which I think has something to do with the placement of the graphs, so I am still using the stock version for that file. Needless to say my graphs don't fit. Right now that isn't my concern because I'm not really looking at the graph display.

My initial question is: Is there something odd/wrong with my .cfg files that is causing my boost # in the logs not to match my dash display which seems correct - at least at idle. Also do you think there is anything else I should be logging, especially when start to tune a newly built engine?" I now notice a type in this post, I reversed the VCM Editor.cfg wording with the VCM Scanner.cfg. (I downloaded the VCM Scanner.cfg file and haven't changed out the VCM Editor.cfg file), I guess I'm a little dyslexic, sorry.

Then I posted in #3 above...
I just looked at the Gauges display and the boost is normal (showing 0 at idle and never went above 23 the whole time. The Boost under Gauges is using PID of STK MAPS. But when I look under the Charts display it is using a PID called Boost2. It is a User Defined one. I see that Boost2 is a Function = ([PID.2339]*9.369)-([PID.2340]/6.895-.53 so what is this? I noticed in the documentation (Help file) that you can't make modifications to a User Defined parameter when the log is open. But when I close the log and then go look at the User Defined ones Boost2 is gone under the User Defined list?

Then after T-Man posted his boost formula post # 6 above "boost - ([SENS.30.KPA]-[PID.2340.KPA])/6.984757"

Here is the same log at the same point in time ... now look at the boost levels ... are they any better? At least it shows zero (or very close) at idle and never goes above 23.xx.

Boost display with corrected formula.JPG

gmtech16450yz, based on what I just posted, do you think the boost values make more sense? Are the formula's right now? Since I know you know what you are doing, I grabbed your files (12-10-12 LNF.cfg, VCM Scanner.cfg) you posted in another thread (http://www.hptuners.com/forum/showth...d-Config-Files) and updated my files.
Here is on section of the VCM Scanner.cfg file:
<userdefinedSettings>
<CustomPID>
<add key="1" value="Calculated Cylinder Air,Calc CylAir,41,45,[SENS.40.MET]*(120/[HPT.NUM_CYL])/[SENS.70]" />
<add key="2" value="Injector Duty Cycle,Inj Duty,0,100,[SENS.112]*[SENS.70]/1200" />
<add key="3" value="Air Fuel Ratio Error,AFR Err,0,100,100*([SENS.120]-[SENS.121])/[SENS.121]" />
<add key="4" value="Boost2,BOOST,0,31,([PID.2339]*9.369)-([PID.2340]/6.895)-.53" />
<add key="5" value="LT + ST Fuel Trim,LT+ST,0,0,[PID.6]+[PID.7]" />
<add key="6" value="STK MAPS,STK MAPS,0,31,([PID.2338.PSI] - [PID.2340.PSI])" />
<add key="7" value="Cam Overlap,OVERLAP,0,91,(([PID.2172]+10)+([PID.2178]+6)-16)/2" />
<add key="8" value="Intake Cam compensated,INTAKE,0,91,([PID.2172]-10)" />
<add key="9" value="Exhaust Cam compensated,EXHAUST,0,91,([PID.2178]-6)" />
<add key="10" value="" />
</CustomPID>
In your 12-10-12 LNF.cfg file you used "STK MAPS" in the gauges display but you used "Boost2" in the Charts display, which you can see above that the formulas are different. Can you tell me why? Remember I'm a newbie HPT so yell nice What I saw was the Boost2 values in the chart display after I made the changes that JimmeS suggested the boost value were inline with the car dash display and the gauge display in HPT. These changes were done on my workstation and when I made the changes on the tune laptop I used the formula T-Man suggested. They use different values but the result look similar.

I would like your response to this because I want to get my config files correct before I do anything else. The logs are worthless if I'm not logging and display correctly. I'll ask again, if anyone has a matched set of cfg files, seems to me there are three that are tied together so I would like all three as a set. Since I'm not positive maybe a HPTuners.com guy could tell me what files to you need to move from one computer to another and have the same log and display info. I would like to build a correct one on my big workstation (as Tim the Tool Man said "Move power!") then move it to my tuning laptop. This way I can have both doing and seeing the same thing without building both from scratch.

[TBSteck]

This just crossed my mind, but are you ABSOLUTELY SURE you flashed the correct tune in? If it's hitting 29psi of boost with 1200psi of fp and 7+ ms of injector timing thats sounds exactly like what you were getting with Term2's tune.

FLASH A BONE STOCK TUNE AND POST A LOG.

Bill, your first sentence was hopefully answers with my lengthy post a couple seconds ago. I will flash my stock tune and post but maybe I should make sure I'm logging correctly first ...

[cobaltssoverbooster]

Boost is more accurate reading the charge pipe sensor which is boost lo res. Since it doesn't see vacuum you must subtract the baro sensor to correct the offset and view true boost. It s much easier to use a custom pid that is boost lo res - baro.

[gmtech16450yz]

Boost is more accurate reading the charge pipe sensor which is boost lo res. Since it doesn't see vacuum you must subtract the baro sensor to correct the offset and view true boost. It s much easier to use a custom pid that is boost lo res - baro.

That's what my boost should be showing in my config. Like I said awhile back though, I haven't looked at what I have in some of my LNF configs for years. It's quite possible that the 29psi my scanner was reading was actually 23 something. Can someone please look at what PID's he's logging and what the chart is set up as? I can't right now. My boost custom PID was always Boost Lo Res minus Baro, like CSSOB said. Tyler, didn't you have stock maps before and now you have Bosch maps? Maybe the custom function is wrong in that config I posted, anything's possible. I know it was always annoying switching between cars with stock maps and ones with gmpp maps. I'll try to get a chance later to find a proper LNF config and I'll post BOTH the config files on here. Tyler, you only need the two for the scanner really, the other one just sets up the editor the way you want it.

Whether it's 23 or 29 psi, what I said still stands. Either is too high for the way the tune is messed up. I find it a little disappointing that since the very first time this OP got an aftermarket tune, he was asking for a "conservative" tune, or specifically NOT a "Race" tune. Why after all of this does he still not have what he asked for?

The tune isn't a soft mild tune. It's designed for racing.

it has an aggressive OS BECAUSE IT'S A RACE TUNE

TBSteck, correct me if I'm wrong here. Did you ever ask for a "RACE" tune?

[TBSteck]

I'm going to find some time today to flash it back to stock. I have some questions, which in turn are concerns of mine, Having a catless exhaust now is there any concerns with a stock tune of the engine going nuts trying to make adjustments when it see the cat isn't functioning very efficiently (especially since it isn't there anymore)? Everything is GXP stock except for the DDM intercooler - which I don't think will have any effect in the tune and the only other performance "go fast" part is the lighten flywheel which again shouldn't effect the tune except it revs faster.

Questions I would like answered for my confidence, since it is a the bottom right now:
1) Will the catless exhaust hurt the engine with a stock tune if I drive it a few miles (10 - 20 or so)
2) Show I make any "tuning" adjustments if I'm going to drive the car 500+ miles to break in the engine?
3) As I have shown from the above logs - if you don't have the right stuff being logged and logged correctly then the log can be misinterpreted and off they go ...
I have included by three files from my desktop workstation, the two files that start with VCM came from this this folder: Documents\HP Tuners\Settings; the other file came from this folder: Documents\HP Tuners\VCM Scanner\Configs and they all three have the 5/28 date as the last modified date.

Thanks guys, let me know what you think.

[TBSteck]

That's what my boost should be showing in my config. Like I said awhile back though, I haven't looked at what I have in some of my LNF configs for years. It's quite possible that the 29psi my scanner was reading was actually 23 something. Can someone please look at what PID's he's logging and what the chart is set up as? I can't right now. My boost custom PID was always Boost Lo Res minus Baro, like CSSOB said. Tyler, didn't you have stock maps before and now you have Bosch maps? Maybe the custom function is wrong in that config I posted, anything's possible. I know it was always annoying switching between cars with stock maps and ones with gmpp maps. I'll try to get a chance later to find a proper LNF config and I'll post BOTH the config files on here. Tyler, you only need the two for the scanner really, the other one just sets up the editor the way you want it.

Whether it's 23 or 29 psi, what I said still stands. Either is too high for the way the tune is messed up. I find it a little disappointing that since the very first time this OP got an aftermarket tune, he was asking for a "conservative" tune, or specifically NOT a "Race" tune. Why after all of this does he still not have what he asked for?





TBSteck, correct me if I'm wrong here. Did you ever ask for a "RACE" tune?

I did ask for a race tune but still have it streetable. We bought this car for one main reason to race this car competitively in autocross and Hillclimbs races. My wife and I co-drive this car. I drive very aggressive when racing, I've set many Hillclimb records (wife has too) and almost always in the top 5 PAX and almost always in the top 8 top raw times in an autocross events. I took 1st place in our annual OSI event last year which includes the 1st and 2nd place drivers in each of the different classes of all the clubs in Oregon. I will admit Oregon has some very fast drivers.

I didn't want a fast street car I wanted a fast race car for autocross and Hillclimbs. I also wanted it streetable because being IT consultants my wife I and will use this as our 2nd car if the other one is gone and in the summer the convertible is nice to drive around. I didn't want a 1/4 mile car - we don't do drags at all.

Bill gave me exactly what I asked for, a Race tune.

[gmtech16450yz]

I did ask for a race tune but still have it streetable. We bought this car for one main reason to race this car competitively in autocross and Hillclimbs races. My wife and I co-drive this car. I drive very aggressive when racing, I've set many Hillclimb records (wife has too) and almost always in the top 5 PAX and almost always in the top 8 top raw times in an autocross events. I took 1st place in our annual OSI event last year which includes the 1st and 2nd place drivers in each of the different classes of all the clubs in Oregon. I will admit Oregon has some very fast drivers.

I didn't want a fast street car I wanted a fast race car for autocross and Hillclimbs. I also wanted it streetable because being IT consultants my wife I and will use this as our 2nd car if the other one is gone and in the summer the convertible is nice to drive around. I didn't want a 1/4 mile car - we don't do drags at all.

Bill gave me exactly what I asked for, a Race tune.

Ok cool. It looks like you're going in the direction you want to go in then. I'll be the one bowing out of your threads. Good luck!

[TBSteck]

Ok cool. It looks like you're going in the direction you want to go in then. I'll be the one bowing out of your threads. Good luck!

Am I missing something here, why would you leave me hanging? I sure hope it wasn't anything I said, if so, I'm deeply sorry because I sure didn't mean it like you must have taken it. From what I have gathered you are one of the most knowledge people on this forum, even I figured that out just being on this forum for a few months. Anyways, I hope you keep at least a silent interest my thread because there are a few of us that like this kind of racing and yours and other senior member's input would be deeply appreciated. If you want to give any input you may always PM or Email me if you want - it would be welcomed. Just think about it - please.