[Jeff@TopGearSolutions]

Originally Posted by Morpheus

look in the first post where a stock motor is knocking Mr. Goodwrench.

I'm sorry how does that support anything about failsafes?

Did you get lost in your own question?

Give this guy some ketchup.

[Clap135]

Originally Posted by InCityPhoto

As stated in thread #399 you actually mentioned killing me... Hmm..

Yes because you seem to misunderstand that knock kills engines, So i gave you an alternate scenario. You being the engine, the bat being knock, and me being the tune.

[InCityPhoto]

Originally Posted by JPSlick

Do the search, or show me your proof, I'm not asking you to reinvent the wheel.

I am just asking, considering Laloosh/Clap started the thread, that unless you can provide data showing me, how the N54 "knocks" while running the JB tune, and the damage that these said knocks are causing, then your thread is invalid and based upon speculation and opinion.

Edit: Fixed the OP

Originally Posted by Clap135

Yes because you seem to misunderstand that knock kills engines, So i gave you an alternate scenario. You being the engine, the bat being knock, and me being the tune.

What amount of knock?

Still going around in circles.

[Jeff@TopGearSolutions]

Originally Posted by InCityPhoto

I am just asking, considering you started the thread, that unless you can provide data showing me, how the N54 "knocks" while running the JB tune, and the damage that said knocks are causing, then your thread is invalid and based upon speculation and opinion.

Is everyone delusional? I didnt start any thread.

LOL.... with comments like these, I can see why you are so confused on how engines work, and how tuning theories apply.

[InCityPhoto]

Originally Posted by JPSlick

Is everyone delusional? I didnt start any thread.

LOL.... with comments like these, I can see why you are so confused on how engines work, and how tuning theories apply.

My tuning theory is that people are running JB4's, Loving them, and there cars are running fine.
And people are running other tunes, and loving them, and there cars are running fine.

[Mike@N54Tuning.com]

Originally Posted by shifterboy45

i guess everybody is either slaying dragons, or running the gauntlet.

this has been very uninformative for the most part -- if someone could see the forest for the trees we could get somewhere--

at least thats what i think...

laying out engine operation basics and then overlay the principles used by the tune to enhance performance using safe practice guidelines could resolve this whole thing quickly.

No, it won't. The basic questions have been asked, answered by many, and there is simply a general disagreement. Thus nothing productive ever comes from these threads.

Here is my summary:

1) Do timing dips constitute knock and/or are they an indication that damage is being done to your motor. No.
2) Is avoiding them a best practice for producing consistent power? Yes.
3) Does the JB4 have a mechanism to detect these dips and learn tuning that will proactively avoid them. Yes, it is being tested/developed now.
4) Do motor failures at 18+ psi, methanol, large turbos, nitrous, etc, indicate that someone running tune only at 13-14psi has anything to worry about? Of course not. More power more risks and more potential problems.

Mike

[Clap135]

Originally Posted by InCityPhoto

I am just asking, considering you started the thread, that unless you can provide data showing me, how the N54 "knocks" while running the JB tune, and the damage that these said knocks are causing, then your thread is invalid and based upon speculation and opinion.



What amount of knock?

Still going around in circles.

small amounts, large amounts, either way if i hti you in the head with a bat, it will hurt you in one way or another. Would not prefer to NOT get hit in the head with a bat to begin with?

Say I hit you with a bat everytime you make an idiotic post. Would you continue making idiot posts if you knew the bat was coming? Or would you make educated posts that prevent the bat. However every once in a while when you slip up, you get nailed.

Thats the point of the knock sensor, not rely on it, but to save you incase you become stupid.

[roninsoldier83]

I think there's a general lack of understand about what a knock sensor's job is on these boards... to those that are unfamiliar, think of a knock sensor as somewhat of a stethoscope. It's main function is to listen for "pinging/detonation" within the engine that is not necessarily audible. On most of the cars I've worked on/tuned over the years, many of them only had 1 knock sensor (as opposed to the multiple knock sensors within these motors). As such, monitoring knock was a fairly simple feat, most piggybacks either tapped the knock sensor wire, or flash based/OBDII data logging software simply read data from the knock sensor.

Typically, during a log, most of the GUI's I've used would just translate the voltage signal of the knock sensor into a count, often referred to as a "knock count", with the higher the number, the greater severity of the knock event. For instance, logging a knock count at XXXX rpm of "1" was not nearly as severe as a knock count event of "10" at that rpm. Rather than relying on retarded timing (as opposed to advancing, not stupid haha), what I would like to understand, is why we cannot translate the data being fed from the knock sensors to the DME into a usable value?

I've experienced audible knock before in the past on my old WRX... damn FPR hose slipped off the intake manifold under 20psi of boost. Unmistakable sound, like shaking BB's in a can... that was a severe knock event. My heart skipped a beat, I knew what it was, immediately got off the gas, but it was too late, the damage was already done. Within a few minutes got a flashing CEL, read the code- misfire on cylinder #4. Checked compression, sure enough, #4 was reading about 50psi low... pulled the slug, and of course the ringland had a hairline crack in it. Either way, there is such a thing as audible knock, but generally only when severe/catastrophic, for most minor knock events, we rely on knock sensors.

The theory behind tuning is fairly simple... I always preferred to tune fuel first with a low boost/timing setting. Adjust/scale injectors (if necessary) and MAF (if applicable, not for these cars). Make sure to get my STFT's/LTFT's as close to 0 as possible at idle and in the lower RPM's. Then start playing with fuel tables in the upper RPM's until I achieve the AFR's I desire. From there I would adjust boost to a desired level, preferably on a dyno to verify gains, but on a MAF car, road tuning while monitoring G/S or some sort of road dyno software would suffice. After boost was at a level I was comfortable with, from there I would attempt to advance timing slowly while monitoring knock & AFR... if I saw knock at a certain RPM range, I would typically pull a couple degrees within that load/rpm range. Make a couple pulls to ensure no knock, and viola, we're good to go.

There's a bit more to it, but in essence, we're not performing brain surgery here, tuning is a fairly simple concept to grasp. However, with that said, even conservative tunes knock... if you tune a car on a 65 degree day, with good airflow, high quality fuel ect, there's a good chance you're going to see a bit of knock when temps hit 105 degrees, in traffic, with a heat soaked intercooler and a bad tank of gas. That's where your knock sensor should be coming into play, retarding timing (boost as well on these cars), richening up AFR's (if applicable) ect.

I wouldn't say that these cars have "bulletproof" motors per se, I would say that they have very advanced knock detection/correction preventative measures that come into play and save a lot of motors. This may come as a shock, but many Japanese "tuner cars" have Open Loop fuel maps under WOT that don't have the ability to "richen" up AFR's under knock. Most also run a set WGDC and do not alter boost on the fly to the extent that these motors do... nor is throttle plate "trimming" even applicable. While the inline-6 configuration is often considered very stout/rigid & balanced, and dissipates heat very well in comparison to many other engine configurations, at the same time, last I checked these motors still come with cast pistons and an open deck (someone please correct me if I'm mistaken). If these slugs are forged, well, when cold I would say that these would be the quietest forged pistons when cold that I've ever heard! Haha!!

Point being, I wouldn't say the motors are just "that tough"... even with a fully closed deck and forged internals, a ringland/piston ring is still only a sliver of steel/iron, it doesn't take much to crack one. For most catastrophic failures like snapping a rod in half, or burning a hole through a piston, yes, internal integrity comes into play, but at the end of the day, ringlands aren't hard to crack under moderate detonation.

The fact that these motors/DME's alter so many parameters on the fly so quickly in order to prevent major detonation events is impressive. In my mind, this is undoubtedly due to knock sensitivity and the knock correction methods that the DME is able to utilize so quickly. I will agree that it was engineered to handle factory boost levels not double stock boost... however, by that same argument, we could deduce that no component within the engine bay should be tampered with to make more power/torque because it would exceed the OEM's specifications. In truth, most OEM's do attempt to put in additional safety nets for less than optimal conditions, i.e. idiot toolbags & soccer moms trying to save a few bucks by filling their cars with the cheapest 85 octane gas available, knowing damn well their owner's manual clearly states 91. I'm sure this is a much more regular occurrence than most of us would like to believe haha, and that the knock sensors/DME's are surely having a field day when said event(s) occur(s)!

Obviously the fact that many of these motors are still alive and running strong after years of abuse/turning the boost up without altering base timing settings is a testament to the adaptability of the ECU/DME. However, as anyone with a lick of tuning experience can tell you, this is not considered optimal. While in this case, riding the knock sensor(s) saves many-a-motor from failure while making substantially more power, at the same time, overall consistency and longterm reliability would likely be increased with proper ignition maps.

By "proper", I'm also not necessarily referring to an OTS flash tune either (Cobb/Dinan/Giac ect). From my experience, OTS maps usually leave a bit to be desired... as like OEM's, they make those maps to be ran in all sorts of conditions all over the country/world. What I'm referring to is strapping your car to a dyno and making adjustments on YOUR car specifically, at YOUR elevation/altitude, running gas from a station that you frequent (preferably under harsh weather conditions/high temps ect). If a person deals with enough OTS maps, across enough platforms, it's pretty easy to see that there are variations from car to car, even from the factory, some motors will make considerably more power/torque than others, and the tunes will be close to spot on, while others will knock all over the place and/or have lower output numbers.

As such, in order to address said variances for optimal performance and consistency, the ultimate solution is to have your vehicle custom tuned as opposed to relying on a map created by another person in a different part of the country/world. With that said, I have not really taken the time to dissect Autotuning on the Procede, or to the extent it can modify said parameters/how quickly it adapts ect, so I'm not going to comment on it.

However, I feel this will fall on many dead ears, as traditionally BMW hasn't really come across as an end user tunable community, most seem to prefer "set-it-and-forget-it chips". On the bright side though, now that these vehicles are becoming more affordable and recognizable as cars that respond well to bolt-ons, I foresee more knowledgeable owners/tuners entering the community, which will ultimately be beneficial to all. Only time will tell I suppose.

Just my $.02

[Jeff@TopGearSolutions]

Originally Posted by InCityPhoto

My tuning theory is that people are running JB4's, Loving them, and there cars are running fine.
And people are running other tunes, and loving them, and there cars are running fine.

Cool story..... move along now as you have no tuning background or experience personally.

[InCityPhoto]

Originally Posted by Clap135

small amounts, large amounts, either way if i hti you in the head with a bat, it will hurt you in one way or another. Would not prefer to NOT get hit in the head with a bat to begin with?

Say I hit you with a bat everytime you make an idiotic post. Would you continue making idiot posts if you knew the bat was coming? Or would you make educated posts that prevent the bat. However every once in a while when you slip up, you get nailed.

Thats the point of the knock sensor, not rely on it, but to save you incase you become stupid.

[Jeff@TopGearSolutions]

Originally Posted by roninsoldier83

I think there's a general lack of understand about what a knock sensor's job is on these boards... to those that are unfamiliar, think of a knock sensor as somewhat of a stethoscope. It's main function is to listen for "pinging/detonation" within the engine that is not necessarily audible. On most of the cars I've worked on/tuned over the years, many of them only had 1 knock sensor (as opposed to the multiple knock sensors within these motors). As such, monitoring knock was a fairly simple feat, most piggybacks either tapped the knock sensor wire, or flash based/OBDII data logging software simply read data from the knock sensor.

Typically, during a log, most of the GUI's I've used would just translate the voltage signal of the knock sensor into a count, often referred to as a "knock count", with the higher the number, the greater severity of the knock event. For instance, logging a knock count at XXXX rpm of "1" was not nearly as severe as a knock count event of "10" at that rpm. Rather than relying on retarded timing (as opposed to advancing, not stupid haha), what I would like to understand, is why we cannot translate the data being fed from the knock sensors to the DME into a usable value?

I've experienced audible knock before in the past on my old WRX... damn FPR hose slipped off the intake manifold under 20psi of boost. Unmistakable sound, like shaking BB's in a can... that was a severe knock event. My heart skipped a beat, I knew what it was, immediately got off the gas, but it was too late, the damage was already done. Within a few minutes got a flashing CEL, read the code- misfire on cylinder #4. Checked compression, sure enough, #4 was reading about 50psi low... pulled the slug, and of course the ringland had a hairline crack in it. Either way, there is such a thing as audible knock, but generally only when severe/catastrophic, for most minor knock events, we rely on knock sensors.

The theory behind tuning is fairly simple... I always preferred to tune fuel first with a low boost/timing setting. Adjust/scale injectors (if necessary) and MAF (if applicable, not for these cars). Make sure to get my STFT's/LTFT's as close to 0 as possible at idle and in the lower RPM's. Then start playing with fuel tables in the upper RPM's until I achieve the AFR's I desire. From there I would adjust boost to a desired level, preferably on a dyno to verify gains, but on a MAF car, road tuning while monitoring G/S or some sort of road dyno software would suffice. After boost was at a level I was comfortable with, from there I would attempt to advance timing slowly while monitoring knock & AFR... if I saw knock at a certain RPM range, I would typically pull a couple degrees within that load/rpm range. Make a couple pulls to ensure no knock, and viola, we're good to go.

There's a bit more to it, but in essence, we're not performing brain surgery here, tuning is a fairly simple concept to grasp. However, with that said, even conservative tunes knock... if you tune a car on a 65 degree day, with good airflow, high quality fuel ect, there's a good chance you're going to see a bit of knock when temps hit 105 degrees, in traffic, with a heat soaked intercooler and a bad tank of gas. That's where your knock sensor should be coming into play, retarding timing (boost as well on these cars), richening up AFR's (if applicable) ect.

I wouldn't say that these cars have "bulletproof" motors per se, I would say that they have very advanced knock detection/correction preventative measures that come into play and save a lot of motors. This may come as a shock, but many Japanese "tuner cars" have Open Loop fuel maps under WOT that don't have the ability to "richen" up AFR's under knock. Most also run a set WGDC and do not alter boost on the fly to the extent that these motors do... nor is throttle plate "trimming" even applicable. While the inline-6 configuration is often considered very stout/rigid & balanced, and dissipates heat very well in comparison to many other engine configurations, at the same time, last I checked these motors still come with cast pistons and an open deck (someone please correct me if I'm mistaken). If these slugs are forged, well, when cold I would say that these would be the quietest forged pistons when cold that I've ever heard! Haha!!

Point being, I wouldn't say the motors are just "that tough"... even with a fully closed deck and forged internals, a ringland/piston ring is still only a sliver of steel/iron, it doesn't take much to crack one. For most catastrophic failures like snapping a rod in half, or burning a hole through a piston, yes, internal integrity comes into play, but at the end of the day, ringlands aren't hard to crack under moderate detonation.

The fact that these motors/DME's alter so many parameters on the fly so quickly in order to prevent major detonation events is impressive. In my mind, this is undoubtedly due to knock sensitivity and the knock correction methods that the DME is able to utilize so quickly. I will agree that it was engineered to handle factory boost levels not double stock boost... however, by that same argument, we could deduce that no component within the engine bay should be tampered with to make more power/torque because it would exceed the OEM's specifications. In truth, most OEM's do attempt to put in additional safety nets for less than optimal conditions, i.e. idiot toolbags & soccer moms trying to save a few bucks by filling their cars with the cheapest 85 octane gas available, knowing damn well their owner's manual clearly states 91. I'm sure this is a much more regular occurrence than most of us would like to believe haha, and that the knock sensors/DME's are surely having a field day when said event(s) occur(s)!

Obviously the fact that many of these motors are still alive and running strong after years of abuse/turning the boost up without altering base timing settings is a testament to the adaptability of the ECU/DME. However, as anyone with a lick of tuning experience can tell you, this is not considered optimal. While in this case, riding the knock sensor(s) saves many-a-motor from failure while making substantially more power, at the same time, overall consistency and longterm reliability would likely be increased with proper ignition maps.

By "proper", I'm also not necessarily referring to an OTS flash tune either (Cobb/Dinan/Giac ect). From my experience, OTS maps usually leave a bit to be desired... as like OEM's, they make those maps to be ran in all sorts of conditions all over the country/world. What I'm referring to is strapping your car to a dyno and making adjustments on YOUR car specifically, at YOUR elevation/altitude, running gas from a station that you frequent (preferably under harsh weather conditions/high temps ect). If a person deals with enough OTS maps, across enough platforms, it's pretty easy to see that there are variations from car to car, even from the factory, some motors will make considerably more power/torque than others, and the tunes will be close to spot on, while others will knock all over the place and/or have lower output numbers.

As such, in order to address said variances for optimal performance and consistency, the ultimate solution is to have your vehicle custom tuned as opposed to relying on a map created by another person in a different part of the country/world. With that said, I have not really taken the time to dissect Autotuning on the Procede, or to the extent it can modify said parameters/how quickly it adapts ect, so I'm not going to comment on it.

However, I feel this will fall on many dead ears, as traditionally BMW hasn't really come across as an end user tunable community, most seem to prefer "set-it-and-forget-it chips". On the bright side though, now that these vehicles are becoming more affordable and recognizable as cars that respond well to bolt-ons, I foresee more knowledgeable owners/tuners entering the community, which will ultimately be beneficial to all. Only time will tell I suppose.

Just my $.02

Good Post..


I have yet to play with the BT tool in regards to knock, but you make a good point in regards to knock count.

I too am used to seeing knock count via datalogs. I'm curious if its available to the end user.

[Clap135]

Originally Posted by Mike@N54Tuning.com

No, it won't. The basic questions have been asked, answered by many, and there is simply a general disagreement. Thus nothing productive ever comes from these threads.

Here is my summary:

1) Do timing dips constitute knock and/or are they an indication that damage is being done to your motor. No.
2) Is avoiding them a best practice for producing consistent power? Yes.
3) Does the JB4 have a mechanism to detect these dips and learn tuning that will proactively avoid them. Yes, it is being tested/developed now.
4) Do motor failures at 18+ psi, methanol, large turbos, nitrous, etc, indicate that someone running tune only at 13-14psi has anything to worry about? Of course not. More power more risks and more potential problems.

Mike

So if 1 doesnt consitute knock then why is 2 using it establish consistent power/engine saftey, cause as you know, if power drops, ignition drops due to knock.

[Clap135]

knock counts are usually nothing more than the amount degrees the ignition dropped. So if you drop 4 degrees of ignition due to the knocks sensor, your knock count is 4

[Clap135]

Originally Posted by InCityPhoto

So you rather get hit in the head with a bat?

[Morpheus]

I guess my confusion stems from the fact that I always thought more boost=more tendency to knock, not necessarily that more boost=worse knock. I'm just asking for proof of this because if it's common knowledge then a link should be easy to provide.

To my limited thinking the cylinder pressures during combustion easily dwarf even a 10psi boost difference. I CAN see that a 10psi boost difference CAN mean the difference between knock or no knock.

Heck, I have an RX7, the most fragile turbo motors known to man. I was right there with you-KNOCK is bad! We also thought you had to run a 10 AFR to keep things safe as well as timing retard etc.

Then I see the stock log you post where a stock motor knocks all the time and I read elsewhere that the AFRs are near stoich!? What's next the world is really flat?

So instead of ad hominem attacks, how about the proof (education) we're looking for?

Edit: I'm beginning to wonder if these newer direct injection cars are designed to run "on the edge" all the time to provide the best mix of economy/power?

[InCityPhoto]

Originally Posted by Clap135

So if 1 doesnt consitute knock then why is 2 using it establish consistent power/engine saftey, cause as you know, if power drops, ignition drops due to knock.

So you are saying every time the timing drop's there was knocking occurring that is damaging the N54?

Originally Posted by Clap135

So you rather get hit in the head with a bat?

I would like you to continue hammering on your invalid point that every time a knock happens, no matter the severity, it has damaged your engine.

[Jeff@TopGearSolutions]

K Count being knock count

In the case of this datalog;

This car does not alter ignition from knock, so its imperative the ignition is SPOT ON.

As you can see here, this is the PROPER way to tune vehicle as there is absolutely no knock present.

I made an extra graph on top to show that there is 0 knock.

3rd gear pull, WOT

[ianthegreat]

Originally Posted by JPSlick

Feel free to send us "links" of proof of no failsafes. Oh wise one.

JP, please dont tell me you are talking about the guy who cracked his turbo exhaust manifold and you are equating knock to this, the same guy who had overheating/water pump issues, the same guy who told us he ran no meth failsafes...

[Clap135]

Originally Posted by Morpheus

I guess my confusion stems from the fact that I always thought more boost=more tendency to knock, not necessarily that more boost=worse knock. I'm just asking for proof of this because if it's common knowledge then a link should be easy to provide.

To my limited thinking the cylinder pressures during combustion easily dwarf even a 10psi boost difference. I CAN see that a 10psi boost difference CAN mean the difference between knock or no knock.

Heck, I have an RX7, the most fragile turbo motors known to man. I was right there with you-KNOCK is bad! We also thought you had to run a 10 AFR to keep things safe as well as timing retard etc.

Then I see the stock log you post where a stock motor knocks all the time and I read elsewhere that the AFRs are near stoich!? What's next the world is really flat?

So instead of ad hominem attacks, how about the proof (education) we're looking for?

Edit: I'm beginning to wonder if these newer direct injection cars are designed to run "on the edge" all the time to provide the best mix of economy/power?

Think about it this way. More boost is more air, requires more fuel, when it sparks, it gives off more energy correct?

So say you have 8psi, the proper fuel, and you spark it
Now compare that to 14psi, the proper fuel, and you spark it

Which one is going to provide more force on the piston? Obviously number 2
Now say you knock during each of those, which knock event is going give more force? Obviously number 2.

[InCityPhoto]

Originally Posted by Clap135

Think about it this way. More boost is more air, requires more fuel, when it sparks, the gives off more energy correct?

So say you have 8psi, the proper fuel, and you spark it
Now compare that to 14psi, the proper fuel, and you spark it

Which one is going to provide more force on the piston? Obviously number 2
Now say you knock during each of those, which knock event is going give more force? Obviously number 2.

So what you are saying that every knock is the same. correct?

[michael1284]

dang...don't yall work or anything? been going at it all day haha...

[Litos]

Originally Posted by JPSlick

And did you tune your STI and your SRT-4's to knock on a daily basis? Better yet, was it tuned with control of all functions of the engine? I.e Fuel boost and spark?

I know for DAMN sure that the STi engines cannot handle knock, AT ALL.

I know 2 guys that blew their engines from mickey mouse tuners.

my STi was a ProTuned Cobb with a 20G, fmic, DW750's and meth. it didn't knock at all due to the fact that it was ProTuned. then i went with an OpenSource tune and picked up an additional 23whp and 28ftlbs with zero knock as well.

my first SRT4 was running 16psi with 100 shot from the bottle. knock sensor was clear "most" of the time. when it would start knocking, i'd back it up. i'd lower the boost to 14psi (stock boost) and knock would dissapear (thank you Aeroforce Scan Gauge)

second SRT4 had basic boltons on the stock turbo - it was my daily driver for about a month before i traded it in for the 335.

i've been in the SRT4 game since 2004 and can tell you that 380-420whp is very common, and has been since late 2003, especially seeing as how amazing the aftermarket is for these cars. bigger turbo such as an AGP 50 trim or a Borg Warner Kit, injectors, TBE and tune (DiabloSport and SCT)

Originally Posted by Clap135

srt4, yes
stis 350 to the wheels you are on limited time
Evos- 400 and you are on limited time.

Plus none of this is ont he stock turbo spitting fire into the engine.

SRT4 - agreed

STi makes @ 230whp and i've seen quite a few 350-370whp STi's that last a long time. my car STILL has the 20G and has been making @ 130whp over stock for 4 years. engine is the weakpoint, but there shouldn't be any reason why the STi can't handle 150whp over stock. 400whp is about 180 over stock - THEN you'd be pushing the limits (but the engine itself would be making close to 440hp). not bad from a 2.5 that doesn't have injector or fuel problems.

and the EVO - i'm going to have to disagree seeing as the stock 2.0L 4g63 can handle EVEN MORE POWER than the STi - the stock turbo is much bigger also.

i live in Houston so i see PLENTY of high horsepowered EVO's, STi's and SRT4's running around. Houston is a massive city with plenty of wide open highways, HAHA !!!!