Data log 928 Motorsports stage 1. Help and advice needed.
06-16-2015, 02:05 PM
#47
Archive Gatekeeper
Rennlist Member
Rennlist Member
The ST2 datalogs spit out data in 0.1 second intervals, you can watch the onset of knocking and how many degrees of timing is being pulled out of each knocking cylinder. So I'm assuming that the EZK is capable of sensing the knock and calculating how much retard to dial in, every 0.1 seconds.
Of course, at 6000 rpm there are 50 combustion events per cylinder per second, so the point about there being 5 per datapoint is well taken.
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Of course, at 6000 rpm there are 50 combustion events per cylinder per second, so the point about there being 5 per datapoint is well taken.
.
06-16-2015, 04:38 PM
#48
Developer
A little more about the FMU being shipped with the supercharger.
#1) Consider this: that many many of our customers are not in SOCAL nor the UK and have no access to a SharkTuner. For those majority of my customers, shipping a supercharger kit with a note that says "now you must find and buy a Sharktuner at about $2k USD" is not an option. And don't even think about borrowing one. Not only are they hard to borrow around the world, but what are you going to do - borrow it again after you upgrade your exhaust? After you change your pulley size? No. I don't want to ship an incomplete kit, and a kit that cannot be tuned on-site so the car can be driven is an incomplete kit. The FMU is simple, works, and allows the customer to easily drop in an enrichment profile. The FMU we use is adjustable for the tip-in point, and the rising rate. And they dont have to buy or install springs.
#2) Also popular is the idea that the supercharger kit should be shipped with a chip. Those kit manufacturers would like you to believe they have a map for every year and model of 928, with every conceivable modification, like an '87 with headers, without, with cats, without; a GTS with stock cams, a GTS with GT cams, a '85 with low compression on a tired engine, a '86 with a tight motor, etc etc. Well, they don't. Saddle up next to those guys and throw a couple beers down their throat and you'll find out that really the best they can do is guess. They take 10 deg of timing out and throw about 15% more fuel in and hope for the best. That's your "tune". Good luck with that generic tune and I wont sell it.
So really - whats wrong with a FMU for the Stage 1 kit, a guy whos adding just 6 pounds of boost? Nothing. They work fine when installed right. And they can always change their tune again later when they make more changes to the car.
And if your going to get serious, get a modern engine management and do it right. Not a chipset-in-the-mail BS solution. Tune YOUR car.
#1) Consider this: that many many of our customers are not in SOCAL nor the UK and have no access to a SharkTuner. For those majority of my customers, shipping a supercharger kit with a note that says "now you must find and buy a Sharktuner at about $2k USD" is not an option. And don't even think about borrowing one. Not only are they hard to borrow around the world, but what are you going to do - borrow it again after you upgrade your exhaust? After you change your pulley size? No. I don't want to ship an incomplete kit, and a kit that cannot be tuned on-site so the car can be driven is an incomplete kit. The FMU is simple, works, and allows the customer to easily drop in an enrichment profile. The FMU we use is adjustable for the tip-in point, and the rising rate. And they dont have to buy or install springs.
#2) Also popular is the idea that the supercharger kit should be shipped with a chip. Those kit manufacturers would like you to believe they have a map for every year and model of 928, with every conceivable modification, like an '87 with headers, without, with cats, without; a GTS with stock cams, a GTS with GT cams, a '85 with low compression on a tired engine, a '86 with a tight motor, etc etc. Well, they don't. Saddle up next to those guys and throw a couple beers down their throat and you'll find out that really the best they can do is guess. They take 10 deg of timing out and throw about 15% more fuel in and hope for the best. That's your "tune". Good luck with that generic tune and I wont sell it.
So really - whats wrong with a FMU for the Stage 1 kit, a guy whos adding just 6 pounds of boost? Nothing. They work fine when installed right. And they can always change their tune again later when they make more changes to the car.
And if your going to get serious, get a modern engine management and do it right. Not a chipset-in-the-mail BS solution. Tune YOUR car.
06-16-2015, 05:18 PM
#49
Captain Obvious
Super User
Super User
Yup....an FMU for a low boost application is perfectly fine. Had one on my '85 for 10 years, same on a boosted Mustang before that. My FMU is not even adjustable but works fine. Makes the engine run a but rich but I'll sacrafice a few HP over cooking the engine. Many of the sharktunners keep removing the safety margin to gain a few more HP. I don't think that's smart.
06-16-2015, 08:00 PM
#50
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I agree the FMU is the A solution. The Sharktuner is the B solution. And a modern engine management is the C solution. IMO, I advocate jumping from A to C and skipping over the B step.
You get a new injector wiring harness, and rid yourself of the problematic and limiting old hot-wire sensor.
You get a new injector wiring harness, and rid yourself of the problematic and limiting old hot-wire sensor.
A little more about the FMU being shipped with the supercharger.
#1) Consider this: that many many of our customers are not in SOCAL nor the UK and have no access to a SharkTuner. For those majority of my customers, shipping a supercharger kit with a note that says "now you must find and buy a Sharktuner at about $2k USD" is not an option. And don't even think about borrowing one. Not only are they hard to borrow around the world, but what are you going to do - borrow it again after you upgrade your exhaust? After you change your pulley size? No. I don't want to ship an incomplete kit, and a kit that cannot be tuned on-site so the car can be driven is an incomplete kit. The FMU is simple, works, and allows the customer to easily drop in an enrichment profile. The FMU we use is adjustable for the tip-in point, and the rising rate. And they dont have to buy or install springs.
#2) Also popular is the idea that the supercharger kit should be shipped with a chip. Those kit manufacturers would like you to believe they have a map for every year and model of 928, with every conceivable modification, like an '87 with headers, without, with cats, without; a GTS with stock cams, a GTS with GT cams, a '85 with low compression on a tired engine, a '86 with a tight motor, etc etc. Well, they don't. Saddle up next to those guys and throw a couple beers down their throat and you'll find out that really the best they can do is guess. They take 10 deg of timing out and throw about 15% more fuel in and hope for the best. That's your "tune". Good luck with that generic tune and I wont sell it.
So really - whats wrong with a FMU for the Stage 1 kit, a guy whos adding just 6 pounds of boost? Nothing. They work fine when installed right. And they can always change their tune again later when they make more changes to the car.
And if your going to get serious, get a modern engine management and do it right. Not a chipset-in-the-mail BS solution. Tune YOUR car.
#1) Consider this: that many many of our customers are not in SOCAL nor the UK and have no access to a SharkTuner. For those majority of my customers, shipping a supercharger kit with a note that says "now you must find and buy a Sharktuner at about $2k USD" is not an option. And don't even think about borrowing one. Not only are they hard to borrow around the world, but what are you going to do - borrow it again after you upgrade your exhaust? After you change your pulley size? No. I don't want to ship an incomplete kit, and a kit that cannot be tuned on-site so the car can be driven is an incomplete kit. The FMU is simple, works, and allows the customer to easily drop in an enrichment profile. The FMU we use is adjustable for the tip-in point, and the rising rate. And they dont have to buy or install springs.
#2) Also popular is the idea that the supercharger kit should be shipped with a chip. Those kit manufacturers would like you to believe they have a map for every year and model of 928, with every conceivable modification, like an '87 with headers, without, with cats, without; a GTS with stock cams, a GTS with GT cams, a '85 with low compression on a tired engine, a '86 with a tight motor, etc etc. Well, they don't. Saddle up next to those guys and throw a couple beers down their throat and you'll find out that really the best they can do is guess. They take 10 deg of timing out and throw about 15% more fuel in and hope for the best. That's your "tune". Good luck with that generic tune and I wont sell it.
So really - whats wrong with a FMU for the Stage 1 kit, a guy whos adding just 6 pounds of boost? Nothing. They work fine when installed right. And they can always change their tune again later when they make more changes to the car.
And if your going to get serious, get a modern engine management and do it right. Not a chipset-in-the-mail BS solution. Tune YOUR car.
I have no gain from recommending the Sharktuner. Other than what is factual, what I have witnessed, and what I have personally learned from using one to experiment and collect data on my personal vehicle over many logging sessions, I do not claim otherwise.
I want additional functionality and capability that is way beyond what the stock ECU or most aftermarket ECU's can provide. I wanted a professional grade system, and chose to go to with full Motec system components with traction control and full dashlogger, GPS etc., with lots of data logging on my 928. Although in a perfect world I would use a Pectel MQ12 with FPGA. This is NOT neccessary to get to 450whp in a mildly supercharged 928. My plans are vastly different.!!!
And your understanding of the Electromotive Tech GT capabilities is also a little wanting... That said - I did say many of several modern EMS will do nicely. Go with what you are comfortable with.
And you know what? Disagree on the topic, fine. The personal attacks? Not useful and they make your other opinions immediately suspect.
And you know what? Disagree on the topic, fine. The personal attacks? Not useful and they make your other opinions immediately suspect.
It is with great encouragement that I welcome every RL reader including yourself to verify all my comments against proven engineering principles and scientific results. As a matter of fact, ALL OPINION should be suspect, and be able to be verified via science. This also includes users verifying ALL of YOUR claims as well.
My reiteration of the fact that I disagree with your methods of tuning and opinion on engines, and can point out the pitfalls of your incorrect statements/opinions with sound science remains just that, calling it as I see it. If you take that as a personal attack on yourself, then it is your opinion and lack of ability to tell the difference that is questionable. Others capable of reading and understanding a simple book by documented experts should be able to do the same.
Here's one for your methods.. You use a BEGI FMU in your kit. Why not call Jim "Corky" Bell in Texas, the founder of BEGI and ask him to tell you what he wrote in his guide to modifying a forced induction motor given a programmable system ECU/EZK with a Sharktuner and all its functionality VS an FMU to raise fuel pressure.
As it is clear that you are unable to read or recognize that I have clearly stated that I have nothing against you in my post at 905am PST, but that I have an issue with the methods you choose to profess to users of the forum, so be it. Your choice, or lack of capacity to read simple english. Not my problem.
It was your method of placing a lambda sensor in one header bank and portraying it as being able to monitor the entire engine's lambda that is scientifically disputable, not you as a person, your action and method trying to convince forum users of scientific impossibility. That was a dispute about fact, not opinion or personal..!! You put a sensor in one bank, I call BS that it can monitor both banks of cylinders as it is physically IMPOSSIBLE for the sensor to do that. Plain and simple FACT.
I am most certainly clear about what the difference is between a personal attack, and an dispute of opinionated rhetoric and versus factual scientific data and results.
Based on your further comments on this thread, it is abundantly clear to me that your evident lack of observation and desire to spew opinion vs fact is further cemented.
As far as my understanding of Tec GT, it is clear.
From Electromotive:
Knock Sensor
The TEC and XDi2 products make use of a piezoelectric sensor that is especially tuned to pickup engine vibrations created by knock (also called detonation or ping). The sensor has a 3/8″ NPT thread for attachment to the engine block or cylinder head. Above approximately 5000 rpm, however, this knock may be masked by mechanical noise; Electromotive calibration software allows the user to program an upper rpm limit to disable the sensor.
They fully admit that their noise filtering software has limitations >5k rpm. This is exactly the point I was making using something like Tec GT versus professional grade noise filtering software used on professional grade equipment such as Motec or Pectel.
The advanced noise filtering software will allow you to filter traces of knock more than 5k rpm...!!! Electromotive allows the user to turn OFF the knock control at the upper limits.. Hmmmm, ok, have the function, but it does not really work at the upper limit, so turn it off... So, what happened to the knock control that we wanted to keep the motor safe at the upper limit..............????????????????????It is you Mr. Fausett that does not understand the methodology in the process of professional grade tuning. The manufacturer of the equipment understands perfectly well that their noise filtering software has a limitation, and has clearly stated that in their public communication.
Please validate and verify to your heart's content what is fact vs what is opinion and marketing to sell you more stuff that you don't need.
Have a great day..!!
Last edited by blau928; 06-16-2015 at 08:44 PM.
06-16-2015, 08:47 PM
#51
Former Vendor
Seems like the simplest and easiest thing to do would to be to install everything that the kit came with, originally.....exactly like the instructions tell you to do it. The kit certainly had to be designed and tested with those components....so that should be the best starting point.
If these is still an issue, after that is done, then you need to come up with a plan.
If these is still an issue, after that is done, then you need to come up with a plan.
06-16-2015, 08:48 PM
#52
As to the Sharktuner: cant hurt, may help, but you must understand its limitations. The Sharktuner software works well.
But its still putting lipstick on a pig, the ability to adjust the settings within the nearly 30 year-old ECU and EZK computers doesn't magically make them able to measure and track intake manifold boost pressures and respond to them. They still can't. And they are too slow to pull timing out when they hear a knock in real-time. And finally - the EZK and the LH do not even talk to each other! How wild is that that ignition and fuel events are not integrated. Porsche had no choice - the processors at that time could not handle both at the same time.
These guys are tuning their ECU with the Sharktuner in anticipation of what the boost should be at a certain point on the engine map. As long as nothing changes from the day they tune it, it works. Any vacuum/boost leak, ignition failure/event, belt slip or supercharger failure, then the map is wrong.
The ultimate solution, if you want to get rid of the FMU, is a modern EMS (Engine Management System). I favor the Electromotive GT, but there are several that work. Then all your ignition and fueling events are controlled correctly, in real-time, and intake manifold pressure is now an integral part of the system. By the time you replace your injector wiring harness and the MAF hot-wire sensor, you could have just about bought one.
But its still putting lipstick on a pig, the ability to adjust the settings within the nearly 30 year-old ECU and EZK computers doesn't magically make them able to measure and track intake manifold boost pressures and respond to them. They still can't. And they are too slow to pull timing out when they hear a knock in real-time. And finally - the EZK and the LH do not even talk to each other! How wild is that that ignition and fuel events are not integrated. Porsche had no choice - the processors at that time could not handle both at the same time.
These guys are tuning their ECU with the Sharktuner in anticipation of what the boost should be at a certain point on the engine map. As long as nothing changes from the day they tune it, it works. Any vacuum/boost leak, ignition failure/event, belt slip or supercharger failure, then the map is wrong.
The ultimate solution, if you want to get rid of the FMU, is a modern EMS (Engine Management System). I favor the Electromotive GT, but there are several that work. Then all your ignition and fueling events are controlled correctly, in real-time, and intake manifold pressure is now an integral part of the system. By the time you replace your injector wiring harness and the MAF hot-wire sensor, you could have just about bought one.
Seriously, I had several of the tuner guys from DFW here at the house as I was trying to get your stage 1 kit to work, a used unit so there is that, and they all could not believe you were still using technology that they used in the 1990's. Yes, going with an aftermarket system would be better, but even these guys who build 1000 to 2000hp 4 and 6 cylinder engines were more happy seeing what a Sharktuner could do than using an FMU to regulate fuel pressure. They sorta chuckled that the ST was using it's small 16x mapping but understood why as it was stuff they played with in the early 2000's and all agreed that it was light years ahead of relying on an FMU to regulate fuel pressure. Not talking about people who think they know how to tune but the guys who play at TX2k15 etc. It's been a great help for my boosted set up having one of them as my neighbor.
Sorry, that post was so full of fail it's amusing.
06-16-2015, 11:09 PM
#54
Captain Obvious
Super User
Super User
Sean,
Were these neighbours of your boosting cars when only FMUs were around? I have a feeling they weren't or else they would know what is possible with them. The FMU is the carburetor and the programmer (like the Shartuner) is electronic fuel injection. They both can do the job if set up right but FI is always better but that doesn't mean an FMU is garbadge.
Were these neighbours of your boosting cars when only FMUs were around? I have a feeling they weren't or else they would know what is possible with them. The FMU is the carburetor and the programmer (like the Shartuner) is electronic fuel injection. They both can do the job if set up right but FI is always better but that doesn't mean an FMU is garbadge.
06-17-2015, 01:25 AM
#55
Racer
Thread Starter
I do appreciate all the spirited debate. Lots of information here.
I do see benefits of a sharktuner, and at first i was going to go with the ST, but opted to take the advise to get this system running as Carl has designed.
I certainly do not think Carl is pushing mis-information to try to sell products. I do not think purchasing an FMU from him is going to make his profit margin soar.
Thats not to say i have ruled out the sharktuner. I will purchase a sharktuner in the future, for tuning and diagnostics. There seems to be a great support group here to assist in setup and tuning when that time comes, but for me the smart option in this situation is to get the FMU.
Thanks again for all the information. I do find it useful, albeit some is a bit mean spirited, but most of the information is useful. Especially to a guy like me who is just getting his shark fins wet.
I do see benefits of a sharktuner, and at first i was going to go with the ST, but opted to take the advise to get this system running as Carl has designed.
I certainly do not think Carl is pushing mis-information to try to sell products. I do not think purchasing an FMU from him is going to make his profit margin soar.
Thats not to say i have ruled out the sharktuner. I will purchase a sharktuner in the future, for tuning and diagnostics. There seems to be a great support group here to assist in setup and tuning when that time comes, but for me the smart option in this situation is to get the FMU.
Thanks again for all the information. I do find it useful, albeit some is a bit mean spirited, but most of the information is useful. Especially to a guy like me who is just getting his shark fins wet.
06-17-2015, 05:48 AM
#56
Rennlist Member
06-17-2015, 07:19 AM
#57
Rennlist Member
The system used in the 928 may well be antiquated in technology terms but nonetheless I was quite surprised to see what it can and does do after purchasing/using the ST2 kit.
Every feedback control system has a time constant- I do not know what it is in this system but it is way faster than 0.1 seconds. I did some experiments reducing the retard steps when I was confident I was close to the limit for given cells and I noticed on several occasions that knock retard applied between 0.1 second sample intervals suggested up to 3 increments has been applied at high rpm's- that suggested to me that the system was responding by the next fring event.
The only problem I have with the EZ system is its sensitivity n that I perceive it may be reacting to noise that is not knock related- i.e. an inept noise filter algorithm.
For this reason I have wondered whether we can use this feature to control the spread of optimal timing cylinder to cylinder- albeit this thread is not the forum to discuss this possibility.
Rgds
Fred
06-17-2015, 11:35 AM
#58
Rennlist Member
Analog filtering is always a compromise between speed of response and the risk of remaining noise resulting in a false trigger.
I believe Porsche played safe and accepted the latter option.
I believe Porsche played safe and accepted the latter option.
John,
The system used in the 928 may well be antiquated in technology terms but nonetheless I was quite surprised to see what it can and does do after purchasing/using the ST2 kit.
Every feedback control system has a time constant- I do not know what it is in this system but it is way faster than 0.1 seconds. I did some experiments reducing the retard steps when I was confident I was close to the limit for given cells and I noticed on several occasions that knock retard applied between 0.1 second sample intervals suggested up to 3 increments has been applied at high rpm's- that suggested to me that the system was responding by the next fring event.
The only problem I have with the EZ system is its sensitivity n that I perceive it may be reacting to noise that is not knock related- i.e. an inept noise filter algorithm.
For this reason I have wondered whether we can use this feature to control the spread of optimal timing cylinder to cylinder- albeit this thread is not the forum to discuss this possibility.
Rgds
Fred
The system used in the 928 may well be antiquated in technology terms but nonetheless I was quite surprised to see what it can and does do after purchasing/using the ST2 kit.
Every feedback control system has a time constant- I do not know what it is in this system but it is way faster than 0.1 seconds. I did some experiments reducing the retard steps when I was confident I was close to the limit for given cells and I noticed on several occasions that knock retard applied between 0.1 second sample intervals suggested up to 3 increments has been applied at high rpm's- that suggested to me that the system was responding by the next fring event.
The only problem I have with the EZ system is its sensitivity n that I perceive it may be reacting to noise that is not knock related- i.e. an inept noise filter algorithm.
For this reason I have wondered whether we can use this feature to control the spread of optimal timing cylinder to cylinder- albeit this thread is not the forum to discuss this possibility.
Rgds
Fred
06-17-2015, 04:54 PM
#59
Developer
Analog filtering is always a compromise between speed of response and the risk of remaining noise resulting in a false trigger.
I believe Porsche played safe and accepted the latter option.
I believe Porsche played safe and accepted the latter option.
I'm checking with some engineers who know more than me about the speed needed to retard timing in real-time. I hope to have their answer tomorrow.
06-17-2015, 05:15 PM
#60
Developer
As it is clear that you are unable to read...
I'll talk to Corky. I know him personally and he is one of our sponsors. We've traded books - his books on supercharging and turbocharging are bibles to me. They are very very good.
He makes these FMU's special just for our supercharger kits. I know he also makes many others.
I cannot remember where I ever said that a lambda sensor in one bank would speak for both banks. Sounds like you may have that bookmarked. LOL IF I said that, it would be wrong. I don't even think a lambda sensor in one bank can speak accurately for all the cylinders in that bank, as it is an amalgamation of the 4 cylinders and can still hide a rich or lean cylinder somewhat.
Last edited by Carl Fausett; 06-17-2015 at 05:37 PM.