Sharing my bad, popping race tunes - looking for some direction

It's a long story but I was pretty well dialed in (by feel) for a brisk 1/8 mile and daily driving, then I got on the dyno in 5th gear (my 1:1 ratio) and found it was on the lean side (12:8 - 13:0). I have never really pulled through 5th to redline, and that explains my weak top end and once in a blue moon top end knock.

So I added a bit of fuel and it would not stop breaking up rich on the dyno. It produced 341 wheel torque a popping zigzag pattern 245 wheel horse. Both the PLX wideband and tailpipe sniffer agreed it goes stupid rich right after 4k RPM. Obviously, I am "doing it wrong" and need to connect the PLX to the software (a link to learning to do that would be sweet).

So I decided to stop messing with the other software I was using all this time and use HPT exclusively - as it is dominantly better for this application. Please don't scream at me or tell me I am going to blow my engine, as I've only had HPTuners for 1 week. I am sharing my tunes because I desperately need advice, me and my buddy Joe have been going back and forth about it in e-mail but at this time I need to open up to a wider audience to chime in. Thanks!

So tune "A" is going back to the first lean dyno, and making some changes. I know I should have just changed one thing at a time but I couldn't resist because there are SO many great options in HPT. The result was a VERY strong street pull and it rockets to 70 MPH with a blip of the throttle in 5th, no AFR issues except it pops hard as hell when I stand on it to downshift in "D". Had to pull over and stop the detonation by re-tuning.

Attachment 44018

In this tune B I made some changes that I though were going to reduce knock, it ran like a bat out of hell, felt like 400 wheel horse and it FLEW when I nailed it but... knock really bad on shifts. So I stopped again.

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Sick of the pinging (more like bombing), I pulled more boost and timing, and added more fuel - thinking it will not knock at all and I can slowly go back up. AFR ended up way too rich, around 10:5 but...still pops on shifts!

Attachment 44020

Sadly I did not log this time, I usually do (some preferred PIDs would be appreciated). I am new to logging with HPT.

The setup is a stock LHU with a 6T50, running 93 pump with full intake and exhaust. Newest PLX in ZZP downpipe. No cats and no boost gauge. My goal is to run mid 20s boost and make 300 wheel horsepower and 400 wheel torque and be able to pull through all gears smoothly whether on the dyno, at the strip, of in 99 degree traffic. I got a long way to go... please chime in if you can and care to. I will gladly answer any and all questions. Thanks!

.88 lambda is usually the sweet spot for DI as long as you have good gas. I believe the LHU has a factory wideband o2 sensor, use that not your PLX. By "pops" do you mean it downshifts hard?

I'm not sure if the LHU has the same knock sensors as the LNF, but either way read this thread- http://www.hptuners.com/forum/showth...ht=false+knock

I'd be very hesitant to run a 13.0 AFR on a boosted car.

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Originally Posted by Ju1ce

I'd be very hesitant to run a 13.0 AFR on a boosted car.

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direct injection has been known to run 22:1 on a lean cruise in some cars.. from the factory ours under full boost around 3200 rpm the max it wants is 14.1:1 afr. 13 is actually safer than stock in theory. it achieves the 13.0 afr with no knock (if everthing else is ok) b injecting fuel at near to spark events so the fuel doesnt heat up like in port injection motors where fuel in in the chamber from the get go on compression stroke so the fuel heats up and then detonates


correct me if im wrong thats what i have learned in m General Motors training at work

DI very different nanimal than port injection.

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Originally Posted by codename Bil Doe

DI very different nanimal than port injection.

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agreed! it has its pros and cons tho.. i work for a gm dealer and we see DI motors come in allll the time missfiring at cold start due to gummed up valves. if they arent cleaned on the regular its bad news bears for that head. we have to replace them most of the time they are so bad

I think I have more carbon on my valves in a week than a #2 pencil factory. You should see the Focus ST and DIZI MS3!

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Originally Posted by noorjSS

.88 lambda is usually the sweet spot for DI as long as you have good gas. I believe the LHU has a factory wideband o2 sensor, use that not your PLX. By "pops" do you mean it downshifts hard?

I'm not sure if the LHU has the same knock sensors as the LNF, but either way read this thread- http://www.hptuners.com/forum/showth...ht=false+knock

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Thank you for your reply. I was very confused about the Lambda settings in HPT. As I read the description of the commanded PE table, the values made no sense. I will post about this shortly.

While I understand the LHU has something "like" a factory wideband, this was discussed somewhere on another forum and I took from it that the latest gen. advance PLX I have is better for tuning. So I will stick with that since there are some setup settings for it in HPT and I don't see any for "stock LHU wideband".

By "pops" I mean a terrible knock / detonation due to high intake temps and combustion chamber pressure and poor tuning. At first I suspected it may be spark blowout or rich pops, but now I have my aftermarket colder plugs gapped to .29 and can tell an distinct difference between the rich burbles and these nasty lean explosions.

And yes when what I think is rich pops occurs, the KR is little to none, but when the hesitation and big puff of letting off boost / jerk happens - there is 5-6-7 degrees KR.

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Originally Posted by Ju1ce

I'd be very hesitant to run a 13.0 AFR on a boosted car.

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Me to!!! But...

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Originally Posted by projectlnf

direct injection has been known to run 22:1 on a lean cruise in some cars.. from the factory ours under full boost around 3200 rpm the max it wants is 14.1:1 afr. 13 is actually safer than stock in theory. it achieves the 13.0 afr with no knock (if everthing else is ok) b injecting fuel at near to spark events so the fuel doesnt heat up like in port injection motors where fuel in in the chamber from the get go on compression stroke so the fuel heats up and then detonates


correct me if im wrong thats what i have learned in m General Motors training at work

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Yes it is interesting that on ZZP's dyno of their boosted Regal, AFR seems to hover around what is traditionally lean - and similar to mine. They made big power and obviously aren't eng left and right like mine.

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Originally Posted by codename Bil Doe

DI very different nanimal than port injection.

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Yes. So anyone care to comment if 11.5 is too rich under full boost / peak torque and if 13.0 is too lean under the same (for DI)?

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Originally Posted by projectlnf

agreed! it has its pros and cons tho.. i work for a gm dealer and we see DI motors come in allll the time missfiring at cold start due to gummed up valves. if they arent cleaned on the regular its bad news bears for that head. we have to replace them most of the time they are so bad

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We used to have to do this ALL THE TIME on the 2.0Ts when I worked as a tech for the Collection Audi here in Miami. However, I though our and the newer DI cars were less susceptible to that problem somehow? I still Seafoam my car occasionally.

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Originally Posted by codename Bil Doe

I think I have more carbon on my valves in a week than a #2 pencil factory. You should see the Focus ST and DIZI MS3!

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Oh shoot, interesting - I will have to look into this! Does beating the crap out of it daily reduce carbon? It does on some cars.

meth injection, seafoam, submarining it in the ocean.

Issue with DI is you don't have the benefit of the fuel cleaning the valves as occurs in port injection. All those cleaning additives in gasolines are useless if they never pass over the valves.

Quote:

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Originally Posted by codename Bil Doe

I think I have more carbon on my valves in a week than a #2 pencil factory. You should see the Focus ST and DIZI MS3!

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lol i havent seen anyof those but i know these DI cars are BAD for it i have a walnut shell blaster that i do and it gets it spotless

Theoretically speaking going lean on DI actually increases power. The problem with the leaner you go is less fuel means more heat. This is where an EGT would actually come I. Very handy. I plan on making a new post soon about temps and tuning around it and when I do I will definitely add fuel to the subject. Now to the important stuff.

I haven't tuned an LHU so I'm not sure how it differs from the LNF and I don't have my computer handy to look at your tunes so bare with me on this advice.

Things that cause Lambda (AFR) to be all over the place including running rich is your physical setup. But Mike it has to be tuning. I know I know but what people don't realize or forget to think about is sensor locations. The motor senses stuff but then reacts to it but if the other sensors don't see it in the same timeframe they are expecting to see it in then it's compensating for something that isn't there yet or something that has already passed. Most commonly seen with intake tubes where the MAF sensor has moved to a further location.

Tuning wise that would cause it would be how smooth everything is and how you have them working together. If you have a huge change the car jumps through hoops trying to accommodate for that and it can cause Lambda to be all over (usually runs way rich and then on it's way back to commanded it can run slightly lean until it levels out at commanded).

Now for the LNF I have noticed that it for some reason will always command .01 lower then what I have it set to command at WOT. Not sure why. Their is actually a small period where I command .91 (the car actually demands .90) and my car runs flawlessly. I would not be concerned with .88 if I were you. My high rpm lambda is actually .88

Knock events of 5-7 degrees at WOT is a great way to kill a motor. Are you sure your running 93? It's either bad gas, terrible plugs, crazy high IATs, or a tremendous amount of timing.

NoorjSS it's not necessarily those things. 7 degrees of knock is extreme yes but it's not always caused by those things specifically. Lots of things can cause knock when tuning other then those things such as not having smooth transitions, running rich in some cases (yes you read that correctly, sometimes adding timing and leaning it out can actually fix this, though at WOT and 93 this shouldn't be the case), other tables that affect smooth flow and driveability, etc. Also if the LHU is anything like the LNF you can also get lots of false knock (never seen that high) and you would just need to adjust the knock sensors. I need to grab my computer and make it home so I can actually view peoples tunes for real help.

That is not to say that other things aren't causing it as stated above by noorjSS

hi looked at your file "C"...
i think you ar are brave man running that thing freakin' lean like that and having all COT and TOT disabled.
your desired PE lambda(sorry i am german ;) ) is at 0.93 this is AFR 13.6!... what is your exact wideband reading?
on my LHU i am running it at straight 0.83 which works fine w/o any knock. had the car on the dyno last week, 512NM/349HP (Engine), I tested alot and also hat to find out the hard way that the engine as long as it is stock can not take more or you rods will blow the block. (remember german autobahn is a bit different than in the US ;), i run it 160mph+ nearly every day, and not pulling it gear1,2,3 until reaching the speedlimit :P )

also all this trq mangement diabled and the max knock airmass table maxed out is a graet way to blow the engine.
raising the driver demand this high and maxxing the torque tables and conclusively lowering PE enrichment torque etc. is also senseless for fuel consumption, the car will be in PE everytime, even if not needed.

cheers tobi

Thank you all for your responses!!! You are all very correct, I need to tell you some specifics about my case to focus in. First let me try to reply to each comment, then I would like to tell you some more.

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Originally Posted by MikeM173

I haven't tuned an LHU so I'm not sure how it differs from the LNF

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Mike, the LHU for all intents and purposes IS an LNF. While I read several people were upgrading to LHU from LNF because "the block is better" and / or it's the latest and greatest, in my opinion and understanding it is 90+ % identical. More importantly, it's physical layout / look / sound / behavior / tuning strategy is virtually identical.

Here are some tidbits about LHU (hoping it helps):

Wikipedia states:

" LDK = A high-performance version of the LNF with 9.2:1 compression. This engine is also known as A20NFT and A20NHT by GM Powertrain Europe.

(2009 Opel Insignia, 2010–2012 Saab 9-5 2011, 2013- Saab 9-3 (NEVS), 2011 Opel Insignia, 2012 Opel Astra J OPC)

LHU adds E85 flex-fuel capability to the LDK.

(2011–2013 Buick Regal Turbo, 2011–2012 Saab 9-5 Turbo4, 2012–2013 Buick Regal GS, 2013–present Buick Verano Turbo)
Also, if you look at ZZP's dyno of an LHU, it is described as an LNF...

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In addition, LHU was one of Ward's 10 best engines in 2012 - beating out all competing 4 cylinders:

LINK TO ARTICLE HERE