How many times should a car be tuned?? (Re: Dumbed down MPFI talk) Hi Paul and V-8 Buick hi-tech types, Let me apologize in advance because this going to seem rather harsh. Still I think this needs to be said because I fear that this is precisely the sort of seriously misguided thinking that pervades the "cloud" age. Sure enough, cloud technology allows us to do this - but is it really what we want? o No: Before we get too excited, let us recall the problem to be solved: quite simply: the engine needs to be supplied with correct amount of fuel and air at the precise moment to provide best possible combustion. Now last time I checked, this is a matter of straightforward physics and chemistry. When I was getting my Bachelors at U.C. Berkeley, this was sort of a problem that a graduate student would be assigned as "punishment" before getting onto the glamorous particle physics (where the :dollar: was ) So if this is the sort of thing that should be possible to solve with a suitable amount science and engineering - why would be tuning your engine over and over again - never mind need to ask human experts from all over the world to do it? o No: There is an saying that seems desperately relevant in this context: "too many cooks spoil the sauce." So tell me, how many experts (and how often) do you need to figure out how to solve the physics and chemistry of an internal combustion engine? I've complained before about my unhappiness about the way aftermarket EFI systems use look-up tables to accomplish tuning. Clearly it is "good enough" - cars work fine after all. However, this precisely the worst possible instance of "digital" - in its original sense of the phrase: chopping up the world into discrete bits. Fuel should never been dispensed by measuring cups. A gasoline engine is an analogue device that should be controlled by analogue functions (like those functions I toiled over as an undergraduate.) The appropriate design for the electronics if a fuel injection system is curve fitting and the mathematics behind it hundreds of years old. Once more as a naive undergrad, I wrote software that did curve fitting - that's what physics undergrads did. Yet today I'm being told that the best electronic technology that can be put into my car is unable to handle the sort of simple mathematics that I did with a computer that had less power than the processors going into those very EFI systems of today . . . . . . . . . Excuse me? ???? Somebody has applied a bit too much technology - and not nearly enough good science and engineering . . . Sorry if this seems beyond what any particular person or company can deal with. Yet, I think we need to be truly honest about what technology has really accomplished and how its misapplication had led us astray. As I understand it, the aftermarket EFI systems rely on what auto-makers have done. Either they have kept the best of the technology for themselves, or worse, in the desperation to meet all the conflicting demands placed on them - they haven't done the basic science to develop suitable computer models of engine combustion. I'll be blunt - human beings should never tune cars! The internal combustion engine is a physical system and it should be possible for us to create accurate computer engine simulations - down to reliabily predicting fuel-air mixture and injection data. With such models, an onboard computer should be able to determine in real time from available sensor technology what the fuel-air mixture to use and when to inject that mixture. At most, humans may need to be involved in adapting the computerized tune to fit the driver's personal preference. That is what technology should be giving us. If we don't have this sort of thing, it is because the greatness that allowed us to win World War II has been allowed to slip through our fingers. I don't mean to belittle our technology that make it possible for folks all over the world to share things. However, any sober look at what this technology has actually accomplished should put things in perspective. To use another modern saying: "None of us is as stupid as all of us put together." The greatest hope for such technology is greater understanding and harmony among human beings. If you believe this is actually happening, check out this headline. Global connectivity shouldn't be the route to improved engine tuning. Sure there will be cases that it is helpful. However, if there is something we have largely failed to do with technology, it is apply it to problems of physical automation. Geeks don't like to get their fingers dirty, so don't tell them about how an internal combustion engine works. To them, it is better to write software to have a pizza delivered than to understand how to get 24 MPG from a 65 Buick Special. For everyone who loves old cars this is very ominous indeed. :ball: These are the folks who see electric cars are the answer and that classic car lover are as obsolete as their cars. Computer networks are simply a tool - not a panacea . . . . Sincerely, Edouard P.S. Those geeks also believe that they can recharge their electric cars at night using . . . . . solar power! :spank:
Re: How many times should a car be tuned?? (Re: Dumbed down MPFI talk) Wow! Where do I start? With all due respect it's clear you don't know what you're talking about regarding this topic, that's probably why you took the EZ way out on your EFI conversion. . I could go on but again with all due respect, you're way out of your league here. It's info like this that has too many people running the wrong way.
Re: How many times should a car be tuned?? (Re: Dumbed down MPFI talk) Edouard My reply was simply to give comfort in knowing that if a person needs help it is available quickly and easily. A support person can look at what is going on remotely and can either give advice or make changes by email file exchange or directly. This is only if a person needs help in the first place. Wouldn't it be great if all products had that kind of support So there only needs to be one cook in the kitchen unless that cook needs help. Your argument is based on a very narrow aspect of what an EFI system is expected to control. You made incorrect statements that were used to support the analogies that comprised most of your reply. Setting up your own premise that is unfounded then building on it for the sake of augument is called a "Cheap Shot" Using an EFI system to accomplish a 24 mpg wagon is your agenda and is not the only task a system is designed to do. How about the rest of us? You only spoke about fuel control. I'm sure you meant to at least include spark. Right? If you look at a list of all areas a system can control, you will see dozens easily! Consider that these system can handle many types of fuels and fuel additions like nitrous and other gasses. There are a pile of functions just to support competition. Don't forget power adders and manifold pressures above 1 atmosphere. The list goes on and if you look at the combinations, you either make hundreds of dedicated units or a single unit able to control it all. The only way a universal unit is going to know what job it needs to do is by someone telling it by entering the initial values. At that point the system is operating based on what you expect as a resulting response by the entries in the software. However you may want a different response and how in the world is the system supposed to know that unless you tell it by making changes in the tables that represent your intent? Are you proposing a system with mind reading? I might be using the system to control a twin turbo, methanol staged injected (24 injectors), 2400 hp, 2 and 3 step limiters that tie into the mag controller, and muti level algorithm traction control, while you can use the same system to control a 24 mpg street car with a TH200 lockout converter tranny. Do you think that some human intervention would be required to make the same system work for both applications? and do you think that my turbo application may require me to ask for help? Your reply was irresponsible but it gave me the opportunity to return the bashing I'm sure you were expecting. Sincerely Paul
Re: How many times should a car be tuned?? (Re: Dumbed down MPFI talk) Just a couple comments. Spark is VERY IMPORTANT, I proved that with tunable crank trigger conversion on a carb. Second, fitting curves is good. The 70s ANALOG EFI tried, but it was strictly a line with a couple bends transfer function. Making a multi input transfer function transfer (for spark & fuel) is only workable with digital systems, which is why (in part) the change was made about 1980. Bruce Roe
Re: How many times should a car be tuned?? (Re: Dumbed down MPFI talk) Paul, again well put. I get sick and tired of people spewing untruths about **** they know nothing about. That's what scares people away unjustly. My fuse gets shorter every day, I don't have the patience anymore that you seem to have, more power to you.
Re: How many times should a car be tuned?? (Re: Dumbed down MPFI talk) Dear Paul and V-8 Buick gearheads, Let me repeat my apologies. However, I think my point simply wasn't understood. My complaint was that what we see today in terms of EFI systems doesn't represent the proper "marriage" of the science and engineering with the "magic" of a global Internet. We have neglected the careful work of building good engine simulations with a heavy layer of information technology that requires way too much of the technical support you are advancing. Hey, how can anyone disagree? Yet, I stick to my main point: shouldn't a physical system require such expertise -once? If a car requires repeated tuning - do you fully undertand this engine that you are trying to tune? No it doesn't, but I trying to make the point that is very difficult to make. Let me try to make that point more clearly. An engine is a physical system. If there is software to model the entire global climate - shouldn't we be able to construct a model of an internal combustion engine such that we can predict accurately all the parameters that must be controlled electronically. Yes I didn't mention the application of spark, but the point is analogous. If the simulation can predict the moment of optimal combustion - it can trigger the spark plug. Today, you can buy software to run weather forecast models that take actual weather data and generate forecasts on your PC. Why don't you run something analogous on your car to simulate the engine and determine fuel air mixture, spark timing and anything else necessary - not based on some lookup table - but via a accurate simulation of what the engine is actually doing? You can add anything you like, that's not the issue here. The issue is - do you understand the system you are trying to tune? It is better to throw up your hands and insist in effect - we cannot understand how an engine with twin turbochargers, nitrous, etc. actually works and return to a world of engine tuning as a black art? This may seem idealistic until you consider that internal combustion engines are . . . . centuries old. Computer simulations of physical phenomena are over 50 years old. There are how many automobiles in the world today? What are the pressures for improving fuel economy, reducing pollution and so on? Shouldn't this sort of simulation be just as commonplace as say simulations of global climate? My view comes from a computer perspective and my complaint is that EFI systems lack what is called an "abstraction layer" so that what is worked on with the computer emulates everyday experiences. Desktop computing was a revolution in user-friendly design. In the same way, no bit of computer technology should appear "naked" but should restore to the user their "workplace." So for your Paul and other professionals in engine design the "desktop" would be a simulated engine. That engine would have parameters based on actual engine components. Adjusting those parameters would no longer be a black-art because the effects on the engine could be simulated in advance. Just as engine design software allows one to compare the effects of different cams, heads, and so on, now the tuning of an engine would be based on an environment replicating the engine itself. No longer would it be necessary to have a "expert tuner" adjust particular lookup table values "because in the past that seemed to make the problem go away." Is this idealistic?? . . . well that gets to the core of my complaint. Effectively, there is a whole "High Tech" world that couldn't care less about how an automobile actually works. So instead of having the sort of simulation software I just described - we have tens of thousands of software engineers writing computer games, Social media toys, and other wasteful matters that cost everybody money and even lives - as my example of a murder driven by Facebook activities illustrates. If 25% of that effort was spent developing good software for EFI systems, what I just described is well within reach. My complaint comes from this perspective. I'm sadly left to say to you Paul, Mark and most of you: "you have been brain-washed into thinking you have been truly well served by the High-tech geeks." Sure you can get your tech-support remotely. What you really needed was well thought out software to start with. A few days ago, I ran into a bug at the core of the Apple script system: AppleScript. AppleScript is decades old - yet no fix. Everyone has to work around it - and that's how people are expected to live. Don't "be thrilled" that the computer industry have given you a few crumbs like global networking. In the end the Internet has become the plaything of spoiled boys and the rest of the world is being sorely neglected. Performance engine technology being only one of many. My vision for a "more better" way to do EFI may see like a hopeless dream. If it is - it is because ALL OF US have been let down by those technologists who promise "not to do harm." Apparently neglect isn't considered harmful. Hope you all can see high-tech for what it sadly is. :ball: Sincerely, Edouard
Re: How many times should a car be tuned?? (Re: Dumbed down MPFI talk) Edouard I was hoping that you would take the time to carefully read what I previously wrote including some reading between the lines and then compare it to the content of your conversation. If you notice I said nothing about tuning in my last reply and your conversation is all about tuning. I'm doing my best to give you more insight on how an Engine Management system works. The bashing was just for fun. A high end system that is running in a closed loop mode does tune the engine exactly to the requested parameters from the user. Your premise is that there is a universally desired tune up that can be technologically obtained and maintained by a software/hardware combination and that there is a failure on the part of the tech community because it ain't happening making us all victims. I'm telling you that if there was a system that you could install on any engine and it would measure every parameter from every input sensor and do all the math and have the engine running perfectly to some specification, it would only be right for a narrow application and wrong for a lot of other users. That is exactly what we have present day and because I like chocolate and someone else prefers vanilla is why the resulting response must be user defined and cannot be predetermined by some computer software. The high end systems do measure some of the same parameters as a weather station along with the engine stuff and tunes the engine accordingly and will also automatically adjust the tables to reduce the deviation which increases system response time. No one has to go in and continually retune as you where suggesting. The experimenters that want to learn more by making changes and checking the results are the ones that are glad to have the option but again it is not a necessity. When we are bracket racing there is a full blown weather station on the trailer connected to a laptop that does nothing but compare previous run conditions with present conditions. Every 2 minutes the system transmits the predicted ET (to the hundredth of a second) to a pager on my belt to be used as the dial in time for the next run. So the technology is certainly there and is far from being a "Black Art" It is just not useful in the way you are envisioning it to be. I will always want a different engine response than the next person even on the same engine type for the same type of racing. The other piece of this that I was trying to explain is that when there is a universal device or system that is expected to control an engine that can have hundreds of different combinations of hardware both internal and external to itself, there is no way for that system to know what that combination is until the user defines the job by setting up the hardware configuration and the initial run parameters in the software and that is where the user may need help more than anywhere else. NOT the TUNING! As you were suggesting once the hardware is defined, the software can develop a base tune up which is fine tuned as the car is run without the need for the user to do any further action. In racing we need to control the tune up because we tune for different reasons and sometime mistune on purpose for the sake of creating a different ET or because of track conditions. There are a lot of other exceptions that you are not aware of that makes any premise for argument invalid. Also remember that everything that determines the operation of an internal combustion engine is variable including fuel. That means that there can be no set tune up and only a base table to work from with the processor constantly calculating the deviation using the sensor input information to obtain the desired output. Again that desired output is defined by a person in the initial setup and even if it software produced, the target values driving the calculations are still defined by a person. You really need to work with a variety systems for a variety of applications before you understand where the shortcomings are and are not. The systems I have worked with are designed both hardware and software by guys that race, not some geek that is detached from the sport. That is the rule and not the exception so quit making statements about subjects that you have no back ground in just so you can support some argument. That is a cheap shot. We asked for multilevel traction control so we could run 2400 hp with 10.5 inch tires, we got it. We asked for an even misfire 2 step so all cylinders would be the same temp at launch, we got it. We said we where switching over to a ProMag 44 and needed an interface for the mag controller, we got it. We needed the unit to operate closed loop with A/F ratios below 4 for methanol, we got it. We basically can have anything we can dream of when it comes to control and data aquisition. So correct me if I'm wrong. You have yet to have hands on with any EFI system giving you only second hand knowlege at best. You also have had limited hands on with engines and still are working to understand the basics. Armed with this you start a discussion on the failures of our present technical community with the pretence of having some authority on the subject. Then if you look at the structure, the arguments are based on unfounded statements followed by analogies that make the whole discussion a little off base. This is a typical stratagy or outcome when an author is out of his/her area of understanding. Sincerely of course Paul
Re: If you want fuel-economy look beyond EFI (Re: Dumbed down MPFI talk) Paul, do you work with the MegaSquirt systems? There is an Android app called "Shadow Logger" or something like that, for if you have a BlueTooth connection to the MegaSquirt you can use an android app to view the tune and data log, but it takes it one step further and automatically uploads the log to a server on the net to be viewed anywhere or time through the internet. It also records the phone's accelerometer and GPS data with the ECU data for even more information, particularly as the vehicle is going around a track. The app is being refined further, looking for more ways to tune with it, but it's pretty neat that it's grabbing the acceleration and location data as well as uploading to a central server so someone across the country can look at it just as easy as the person next to the car.
Re: If you want fuel-economy look beyond EFI (Re: Dumbed down MPFI talk) I have not had the opportunity to work with the MegaSquirt system. Thanks for the information on the phone app! That's what I was talking about! How cool is that! The great part is there can be multiple people anylizing the data at the same time which gives a better chance to catch a problem that might have been missed otherwise. The trouble shooting aspect is something I didn't include in the above discussions along with many other uses for remote data access. The best reason is, it is just plain fun. It's even more fun when you analyze the G meter results and give the driver a bunch of grief over his driving skills. Paul
Re: If you want fuel-economy look beyond EFI (Re: Dumbed down MPFI talk) There was a time when you had two basic types of folks... ones that could tune awesome but didnt like or pretended not to understand the computer controlled setups. The other guys "got" the interface just fine and maybe even wrote their own code as a hobby but fell short on the tuning. Those days are gone! You don't have to look any further than the Buick turbo guys for examples. Adding and removing fuel where you wanted as well as playing with timing to see what changes in spoolup took place was actually getting results for us on one car. If WE could do it a lot of people could - and did. Lock/Dont lock converter. Lean cruise for hway. Antitheft. Big injectors that don't behave like it... were all common place years ago. Todays systems are VERY capable and much more so than the 80s GM 8bit setup. The guys that can both tune AND make changes via laptop are common now. Boost control, closed loop fuel/timing, traction aids, and even a valet mode are all available without getting dirty (once the dirty work is done). The performance numbers don't lie! PS: I once got 22mpg w/455 and Qjet no OD. Had to drive at 50mph though
Re: How many times should a car be tuned?? (Re: Dumbed down MPFI talk) I suspect that as well, that's why I'm not wasting my time trying to reason with someone who essentially doesn't have a clue. I worked in an auto parts store many years ago when I was a teenager. There was a guy that came in from time to time that was a first rate engineer, but when it came to cars he was a moron, although he thought he was the next Smokey Yunick.
Re: How many times should a car be tuned?? (Re: Dumbed down MPFI talk) How about this. Consider the intake valve. The gate way to the cylinder. It's either open (on), or it's closed (off). Sure there are varying degrees of "on" but there is only one type of "off" that ends the sequence. Sounds pretty digital to me. That's the reason fuel puddling is a problem, the valve get's turned on and off and on and off and on and off, rather abruptly too. In either case, short of direct injection both EFI and carbs are supplying fuel when the valve is off simply to ensure the supply of gasoline is sufficient for the power expected.
Re: How many times should a car be tuned?? (Re: Dumbed down MPFI talk) Dear Paul and V-8 Buick engine gurus, Okay I'm willingly admit to all the limitations you mention here. However, I'll have a corner of expertise of my own and my hopes were that you'all would see what liberating possibilities are possible if you got the right kind of support from that corner of the world. Your right, I'm arguing in abstractions. However, I don't think my abstractions are unreasonable. It is possible to create computer models of something as complex as global climate and intersellar systems like black holes. Does your expertise allow you to conclude that it is beyond information technology to come up with a universal architecture to model the physics and chemistry of any internal combustion engine that can be built? My understanding of the science and technology sees no such limitation. Should we be truly so pessimistic as you insist? I've tried to make my point clear. I'm not faulting those who actually work on engines and indeed I've tried to make it clear my profound admiration. I thought my complaint was clear: you haven't been given reasonable tools from the software world to do your job properly. Let me try to make my analogy of the computer desktop again. Before the Macintosh, people typed obscure commands to get computers to do what they wanted to do. After the Mac, what they wanted to do was reflected in the very experience of using a computer: there were pieces of paper, folders, and places to put them. The office worker was given in software an emulation of the world they physically worked in. So change the context to using electronics to control an engine. We are back to days of MS-DOS. Yes, I haven't looked in detail at the various bits of user software. However, the core of all speed-density EFI systems is a set of lookup tables. Exactly what do those values represent? Do all these values represent parameters that correspond to physical properties of the engine? If they did, nobody would call it "lookup table." You Paul and everyone else working with engines have been forced to become computer programmers. As someone who has done this sort of thing, it goes almost all the way back to programming a microprocessor in assembly language. It is about as crude a user-interface as computing can be. What I'm proposing as an alternative is a layer of software that becomes the "desktop" for the engine world. Instead of lookup tables, software uses physical properties of the engine itself and presents the user (you Paul) with software generated emulation of that the engine is actually doing for the given parameters selected for the EFI and other electronic control systems. If the engine isn't performing as well as it could - the simulation shows it - and simulates the underlying physical processes that are degrading its performance. Now you are back to designing engines and when you try to get the best performance out of an engine - you are attempting to understand the mechanics and engineering of that engine. Isn't that what you are really interested in? To put it in a nutshell I'm asking if the present capacity to communicate with the EFI hardware (effectively the language to communicate) truly allows you to express your expertise as an engine builder and optimizer into that electronics? Okay, call me ignorant, but it sure seems to me like everyone in this arena finds themselves unable to express what they want the systems to understand. That's the sort of communication problem information technology experts are supposed to solve. Perhaps you disagree, but I feel that information technology has failed you Paul and everyone who provides internal combustion engines for whatever the applicaton. Now you can insist that what I've describe is an impossible dream - congratulations, by that very insistence you gone a long way into making it a self-fulfilling prophesy. "beware of what you wish for . . . you might get it." With a heavy heart, Edouard P.S. There seems to be sense "personal insult" here. What I'm describing here is well-beyond what any person or company that caters to the V-8 Buick crowd can do. So I'm not "blaming" anyone here. Nonetheless, we all suffer when things could be better and aren't. Whether it is classic cars being junked because people can't afford the gas or people pushed into poverty because the country spends too much of our GNP on oil, we all have a real stake in questions like this. Steve Jobs is a good role model for this. Sure we cannot wish miracles into existence. Nonetheless, if we don't set standards of greatness for ourselves - what hope do we have of ever reaching them?
Re: How many times should a car be tuned?? (Re: Dumbed down MPFI talk) Simulations and models are not substitutes for actual tests and real life. Global climate models are b%& $h!!, and don't predict jack. Model's on black holes are being revised all the time. Way too many people actually believe models are real life, and research scientist are the worse, when in fact they are meant to emulate real life and more often than not can't because the number of influential variables are so large, uncountable even, that they are limited by that. I hate to use the term garbage in, garbage out, but it practically comes down to that. Maybe model's are like baking a cake with a couple ingredients missing? If engine models were perfected, then GM, Ford, Honda, Dodge, etc wouldn't be spending multi-millions of dollars on dyno's and engine designs, because engines and fuel management would of been perfected in the computer software and all would have the same engine. Basically it would be nice to have Star Trek level of computing power, but all we have today is look up tables because so far millions of dollars (billions?) and decades of research haven't generated the perfect model for air flow and internal combustion dynamics. Signed "Your Local Geologist and Car Enthusiast"
Re: How many times should a car be tuned?? (Re: Dumbed down MPFI talk) Edouard What you are saying is appreciated and I understand your view point. There is no personal insult taken. The only reason for the rebuttal was to keep from blowing out readers that might consider EFI as a possibility. You yourself are an advocate of EFI but you couldn't tell that from your initial remarks. As far as your point, no matter where you are technologically you are always behind the possibilities and what tools you have today, even if they are the latest and greatest, become obsolete in months. However that is not an issue here and I'll explain in a moment. What you are describing is called the dyno room. Equipped with pressure sensors and laser tools and even transparent cylinder heads the poppet valve piston engine has been analyzed to death. From there we can see that certain indicators can be used to determine engine performance and that is what the present day EFI systems use. We also know that using those indicators gets us close enough to the optimal response that whatever is left on table is not worth going after. I'm going to put this statement out in the open so you don't miss it this time. We don't always want the optimal engine performance tune up and there are so many variations in engine response wanted by different users that there has to be a way of telling the engine management system what that desired response is!! After that the present day systems get us to where we want to be and no matter what advancements there are in software you aren't going to get any closer because there ain't no closer to be had! What the new technology does offer is the ablity to investgate and control better engine mechanical configurations which is the arena that is so far behind it.. (Add your favorite conspiracy theory here). I don't intend to start a mechanical discussion here so please don't either. Thanks in advance. Going back to software real quick. When code was written in machine lanquage it was very compact on almost never locked up due to open ends. I worked for GE back then. As soon as our software group started with higher level language they started asking for more memory because the higher level languages required libraries as part of the source code and took up a lot of memory space. Sounds a lot like look up tables to me! Paul
Re: How many times should a car be tuned?? (Re: Dumbed down MPFI talk) Dumbed down. I am not a phisics or chemistry major. I am not an engineer(although this fall I'm going back to school for that). I'm just a dude who wants to find an early 50s Buick with no motor or trans, and make a cross country cruiser that can still smoke some tires. I realize that a Q-Jet can do this for me, but part of me wants the satisfaction of accomplishment, and the other part of me doesn't want to tweak a carb every 200 miles. I plan on building either a 455 or a Nailhead, and adding some sort of EFI. I AM BROKE! I am a laid off construction worker who is going back to school in the fall. So $1600 on an Accel system is not happening. I'm selling my Rivi to fund this project, so funds will be evtremely limited. I was just turning to you guys for suggestions on how to efficiently accomplish this, on a budget, as well as creating a reference point to someone else in a similar situation. I like the megasquirt system because I can build it myself and save a ridiculous amout of money. Also, since there are other people on this board that are experienced with it, that helps me a LOT. I didn't mean for this to get out of hand. I just wanted simple suggestions and ideas to keep the brain working.
Re: How many times should a car be tuned?? (Re: Dumbed down MPFI talk) Stu Actually it isn't the way it appears. Edouard and I like to pick on each other in a friendly dual. The hopes are that there was still a lot of usable insight within the content of the replies from all who participated in the discussion. As you can tell there are some frustrations because both of us are also in the middle of engine projects that are on hold because of parts supplier issues. So what better way to spend time than here on V8Buick. Aside from the EFI purchase there is also the fuel pump, regulator and fuel tank as additional cost. If it is a port injection then there is the cost of adding injectors to the intake manifold. Focus on the engine first and possibly start with a carb setup, then as the budget allows go to EFI. This will also let you compare the differences between the two setups. What type of engineering are you looking at doing? Paul
Re: How many times should a car be tuned?? (Re: Dumbed down MPFI talk) Every single time we talk efi on this site it goes to heck. How bout this, new cars have way too many electronics and not enough brains. I can show you a fundemental flaw in "reliable" oem application that can make you question the sanity of the designers. Jump in an L99/LT1 b-body and try to drive it with a loose connection on the coolant temp sensor. The car will quickly alternate between a low rpm stall condition and lunging forward at max torque. With the brakes fully locked the car can actually surge forward as it outpowers the brakes. The issue is that the car is seeing a negative value on the temp sensor (defualt reading is minus 20 or so) and the car instantly goes full rich to try and heat the car up to allow good emissions readings. When it goes full rich the car launches forward. When the o2 reads full rich it cuts fuel and timing which makes the rpms drop to a point where the car almost stalls. This pattern happens about once every 2 seconds. Shifting into park will cause a pure power spike and may actually show you where the rev limiter is set. Someone in the GM engineering department should have asked themselves why a coolant temp sensor would cause such a dangerous situation, especially when the iat sensor is reading normally. I'm going out on a limb and saying that elagache is basically just saying that at this point in our technological history we should be able to count on a system that is designed and tested on our specific brand engine and we should also have faith that it doesn't have the same fundemental flaws that have popped up in the past. After 30 years of experience we're still at a point where we have to guess at a starting point and then hope we can adjust it to where it should be without running out of adjustment or blowing something up before we get it adjusted. How many of those aftermarket units can only raise pressure or flow a certain percent before the ability to tune is maxed out. That's a problem that should have been solved back in the tbi days, but it still pops up from time to time. How many systems use fuel pressure increases to cover up a fuel supply problem just so that they can say it fits both small and big blocks. That's an issue where the sales department has more clout than the engineering department. I personally love efi and think it can do great things. I'm also in the process of working on both a '94 efi car and a '63 straight 6 and the less electronics an engine has the easier it is to track down shorts and troubleshoot slight problems. If efi was as basic as the old mechanical fuel injection systems, or even the bosch analog systems, than I believe people would be far more forgiving of the small flaws that are common on these new expensive systems.
Re: How many times should a car be tuned?? (Re: Dumbed down MPFI talk) Thanks Bammax Aftermarket EFI is one of the areas that I feel has not caught on as fast as it should and can cause a person to become overprotective of the subject. My apologies for contributing to the fiasco. The issues you brought up are certainly a contribution to the problem of making the move to EFI something that a person can feel confident doing. It would be great to be able to purchase a system for a Buick 455 configured closely to the specific engine build, put it on and have it fine tune itself from there. The system would include the timing wheel and trigger sensor along with the cam sync signal hardware. I added this because it is one of the main obstacles in installing an EFI on an older engine. This shifts a lot of the responsibilty for the success of EFI to an engine specific forum like V8Buick. What we need more of is specific installation examples and less debate. A great example (and forgive me for not mentioning others) is TheSilverBuick. The thread had continuing progress reports and pictures showing important detail. If every time a new EFI installation was posted especially of different brands then a person could see what was involved and could make a lot better decision and feel a lot more confident. And yes, the next Buick EFI installation I do will be posted Paul
Re: How many times should a car be tuned?? (Re: Dumbed down MPFI talk) Was an engine/system that hasn't been used in at least 15 years cited as new?
