~ 608-738-8606 ~ W1710 State Hwy. 16, Suite 3, Bangor, WI 54614 ~
Tis the Season for LS Swap-idge!
‘Been Get’n many calls about LS Swaps, Conversions, and ECU/PCM Work. So its High Time I put up, offer my 3 cents, yes one for the ladies too, and put it down for ya, how to make the Grades, Playa’s. Seriously though, there’s so much bad information out there, misinformation, half-truths, YouTube of cobbled junk, trips to the junk yard, hacks playing hack! Ugh.
First and Foremost, If you’re planning an LS Swap…Find a Good Donor Vehicle to start from. Don’t Piece together a wiring harness from different vehicles, Gen 3 on top of Gen 4 stuff, Don’t cobble things together because some guy in a forum says he did it, and certainly don’t mix and match PCM’s and wiring harnesses. Look if you want a GOOD experience making a swap enjoyable, start with a donor vehicle by pulling the harness and engine together, and trans if you want that too. Then you will have harmony within your electronics…Same PCM, Same Engine. That’s a big one, and the first-place people stumble, make stupid purchases, get heartburn, greif, divorce, alimony, and sometimes additional taxation. Don’t play with the Tax man. Good advice.
Anyways, Every PCM is different, just like every car is different, because of the Features… Features sell cars, which helps increase sales. Every PCM comes from the factory with its own set of features and respective tune, mainly just subtle differences in engine programming. So naturally every model has a different electronic road map, So to speak. Now if you take one PCM from a vehicle, and try to use it to power an engine from a completely different specimen, you get talk soup…No Really, Features and certain critical engine components won’t get the signal they are looking for, will send false signals, trigger codes, alarms Lights, chase Ghost’s, and then you have a lame duck on your hands. That’s when Ghost Busters Kicks down your door. Now You get to clean up the mess. Not really. But you get the point. I have encountered a common mistake where guys will buy a PCM off Ebay and it won’t start the engine. So they send it off to a guy that gets the VATs taken off and puts a tune in it. It usually starts, but then things won’t work, like air conditioning, Dash lights won’t work, or stay on, ect, ect. If you’re a guy that doesn’t care about Check Engine Lights, then stop here. If you want the job done right…Stay Tuned Playa. And if you’re the Super Smart guy that thinks he’ll just wire in a Dakota Dash as a work around, think again, you’re in for it the worst.
A hack for the Hacks. Instead of sending the PCM to a tuner, the client could have found a guy that can flash the VIN into his PCM. Yes, it’s a separate thing from a tuner flashing a tune file. But that would require that you have the VIN of the Donor Engine you started with, you know, the greasy engine currently resting on an engine stand, 400-pound chunk of steel mass, doesn’t roll well on the carpet. What I mean when I say, “Flash the VIN,” is the Software written by the Factory, with all the special features, specific to that vehicle, along with all the powertrain programming, and its identifying VIN required by the DOT, is written (Flashed) onto the PCM. Most Dealerships can do it but there is a caveat to that too. That nugget means there must be a car installed onto the PCM already (Laughter) when you show up to the Dealership. Further, NO Blank PCMs serviced by Dealerships. Another dead end in the surreal life of a swapper. Kinda like marrying a stripper. It was good at first! Then ah……Never mind. There are vendors out there that have the capability to flash VIN’s onto PCMs regardless if its blank or carrying a tune. I Use Flashmaster’s when I need a PCM. They’re poor Bangles Fans over there in Cincinatti, so give them a break, they need it. But they are affordable! They go through the PCM, clean it up, flash it, replace the battery if it comes with one, and mail if off to ya with the VIN of your choice.
The reason why having the VIN flashed is so important is when a PCM encounters a new Cam or Crankshaft sensor, it could possibly trigger a, “Relearn” protocol. When the PCM senses a new Crank Sensor, it shuts off the fuel pump signal from the PCM, but will still allow the engine to turn over, primarily on Gen 3 PCM’s. The tattle-tail is when you turn the key to the run position, you should hear the Fuel Pump prime momentarily for 5 seconds or less under normal conditions. When you’re stuck in relearn mode with a Gen 3 PCM cause you pieced together your harness, engine, and PCM, you won’t hear the Fuel Pump prime with the key at the run position. The relearn can be done manually in 30 minutes if you have a Gen 3 PCM (99-2007ish). However, the relearn process in a Gen 4 can be a little more complicated in that the engine has to be running during the actual, “Relearn.” If you can’t get your Gen 4 Started, or to run properly, the Relearn process can be a tough trick to pull off. I haven’t personally experienced a Gen 4 PCM cut the fuel off in a swap with mixed matched parts, but that doesn’t mean it won’t in your case… Most swappers that go after the Gen 4, 58 Tooth Crank, is because the PCM runs off the Drive-by-Wire Throttle body. Which also means no ugly throttle cable weeding up the beautiful garden. DBW also requires an electronic accelerator pedal, and another reason to reinforce for the donor vehicle concept. Gen 4’s have the drawback of going into limp mode if you apply too much power, or the Map sensor reading doesn’t match the requested throttle position vs Engine Torque. Definitely something to consider if you’re toying with power adders. Again, Doesn’t mean it cant be done, just means Additional tuning and attention to tuning detail is critical, and harder on the checkbook if you know what I mean.
So don’t ever buy a blank PCM, get it all done in one shot. If your gonna go through this DIY Project, that can be a huge hassle cause you’re too stubborn to have it fail, then you should start with a donor vehicle or just pay the junk yard to dismantle all the parts on your list. The engine you’re swapping wont know what car or truck its in, But, the more you make it believe it is still in that same car or truck it originated from, the happier the motor will be. In other words, make the engine think everything Still works as it should. The more you mix and match, the higher your frustrations will be. The more stuff you alter or remove, the greater the chances of chasing ghosts. And that goes for aftermarket parts too. OMG! I have my own cuss words reserved for parts that are labeled for a category of engine that don’t fit, and need deeply skilled modifications in order to fit. For Example, I have had to cut and weld fuel rail brackets to the right height for stock injectors so the rail doesn’t pop off under 60 PSI, like a pubescent teenager challenging your morals. Slapping the parts in the face just doesn’t offer the same result.
Be Careful of making any modification, to the harness, Injector, Throttle body, Sensors, and Fuel System. They can and will have unintended consequences. Sensors might look the same but are coded with a different 5-volt reference that could ultimately provide you with the wrong data/gauge reading. Anytime you change how the engine breath’s, including an air filter, your new engine probably needs a new Tune written. For Heavens Sakes, stay away from Ebay Fuel Injectors. Not to say anything bad about the vendors from Ebay, or their products. But Ebay Injectors seldom come with data required to make a solid tune possible. An Injector needs data, like plant life needs water. Having the right injector data makes the whole tuning process/LS Swap fun and worthwhile. Not having the proper data means guessing, which can lead to serious head scratching, staring into space, loss of patience, talking to yourself out loud, heartburn, headaches, fever, chills. Enough of the medication commercial. The wrong injector data can over-fuel, or worse, under-fuel at Idle or WOT. You will have problems you can’t explain, and questions you’ll be asking your cousins, sisters, ex-roommate’s, Forum Administrator, side-mechanic from Louisiana you bailed out and got a “Solid” coming to ya. Another Professional suggestion is to stay with the throttle body that came with an intake manifold. That includes aftermarket intakes and Throttle bodies. They are better matched. I have heard whistles when using spacers and adapters on throttle bodies. If you have OCD and your hearing that, Oh Boy! And its already been proven that a larger throttle body won’t make a single HP more than a stock one for a specific factory intake. Moreover, the Larger TB on a smaller Intake opening could possibly cause turbulent air that throws off your MAF sensor and fueling calculations at low/part throttle speeds.
Beware that you might have to rearrange or, “rework” the harness to fit, beautify, or make serviceable sense of the installation. Like moving the harness around or behind the intake manifold so you can admire the beauty of that overpriced Air/Fuel Hardware. So that means be very deliberate to take care of the old harness, and not cut off unused connectors like smog and ABS. Just leave the unused connectors on the harness, tape them off to protect from moisture, and burry them in a corner cranny somewhere. Stray voltage can haunt you, born from a cut harness connector looping or grounding due to poor cobblemanship. Bad DNA could be the primary fault there too… Never the less, the integrity of the harness is key. Ask any Veteran GM Mechanic and they’ll tell you, LS’s are known for having stray voltage issues.
And now the most important part. MAKE SURE your fuel system is up to par for Fuel Injection. The Factory does things that are unexplained and often contain unknown reasons that have deep background explanations for the good of your ride and the EPA’S Lofty goals. Meaning, making sure the Fuel pump Configuration/Location, Line Size, and having a proper return line will keep you from getting into vapor lock, hard starting, unknow idle anomalies, and unresponsive fueling changes. The Factory really does do things for a reason, even if they sound stupid, guidelines to stick too like the words written in the bible. So often I see, hear, and have the unfortunate opportunity of diagnosing issues related to a fella figuring things, “Would work,” on fuel system installation. It annoys me to no end. And then on top of that, guys get upset that you called attention to their bad choices, and then THEY have the audacity to get upset. Hay man, I call’em as I see’em. Holley has diagrams of the best suggested Fuel System configuration as well as charts on fuel pumps and matching regulators, line, filter, fittings size, amp draw, ect. Don’t get any big Ideas about how you think substitutions can be made…This is exactly why I am writing this article. Just stick to the diagram and you’ll be fine. Moreover, your trick installation means nothing if you don’t properly size your electrical wire. So if your battery is in the engine compartment but your fuel pump is mounted near or in the fuel tank, then you need to select the wire size for the pump that meets the voltage drop due to the length of wire you use. Deep summer heat, Fuel Pumps, and low battery voltage can equate to fires during high amp draw situations. Its happed and will happen again if you temp destiny.
The last thing I’m gonna bark about are Grounds. Proper Grounding is Paramount. You can solve so many problems by spending the money on large ground cables. Cast your mind for a moment. Your ignition system is putting out megajoules of energy moving at the speed of light down the wire and to the spark plug, and then Bang, you have a misfire for some bizarre reason. Well, all that energy has to go somewhere, always through the path of least resistance. Now if you don’t have the proper ground cables, including the size to handle the Lightening your coil is emitting, the stray voltage can backfeed into other electrical devices attached to adjoining ground paths, including electronics powered off, and subsequently, “Letting the smoke out,” of your ECU/PCM. A phrase Holley Tech’s like to use when the ECU gets Fried.
So in closing, I just want to leave you with this. Of course anything can be done, YouTube is full of it. But my experience in this field has added up to these proverbs I have just bestowed upon you. Remember these guidelines apply for using Factory LS Parts along with a Factory ECU/PCM. Using a standalone ECU means some of these rules don’t apply. However, following my advice will lead you down a path of so much less frustration, you’ll be looking in other places for the world to frustrate you. That’s how much this info will help! Good luck to all the hardheads reading this that believe they know more than this Author….My Journey in Tuning, electrical, mechanical, and science has really been an investment in education, as with any trade. An old school quote and good one from Bob Vela, “If your gonna spend close to the same amount of money on a project as it would have cost to hire a contractor, then you’re better off hiring a professional in the first place.”.
It has come to my attention from the Tuners Network that there are a few bad apples spoiling the bunch. Apparently, there are Tuners using a software program by the name of DynoGen for less than honorable purposes. This Program allows the user to generate a 100% fake Dyno graph and uses some spiffy graphics to produce a very eye pleasing Dyno Graph. The intended use is for research purposes only. However, the ladder of our colleagues use this program to inflate actual Dyno numbers to achieve results worthy of customer acclaim.
In this life, Reputation is all we’ve GOT! If you’re a Schmuck, people will eventually find out. If you put out a quality product or service, word will spread fast! When I bought my Chassis Dyno I made a promise to myself that I would never use a button or device to alter my work. Not even just too see, No Shenanigan’s period… I knew that I would have to let the truth lay, and challenge myself to get better. The results will do the talking, and if I am ever dissatisfied, I make it my mission to uncover the reason why. Brutal Honesty is the best policy. So I want to go on record and explain some of the ways to tell if your Dyno results are truthful, or if your Tuner is giving you the sham!
The institution known as the Society of Automotive Engineers, SAE for short, has created precedent setting standards for the automotive industry since 1904. Did they even have cars then? Anyways, they set the standards for everything from Design, Fasteners, Torque Pattern, to mathematical calculations for finding things like Traction, Brake Horsepower, Torque and even Drag. Well I wont thump you over the head with the SAE Rulebook, but I will tell you about one important Standard they created that should be understood like the word of God for all Tuners to abide by. That Standard is J1349, “Certified Power.” The SAE spells out the many standards on performing this voluntary certification and the calculation methods used to collect data and ultimately arrive at true, “Horsepower and Torque.” The reason all this background information on the SAE is so important is because every Dynamometer Manufacturer in the U.S. uses the J1349 method as the basis to provide Horsepower and Torque data in some form or another.
So if you're ever in the market to have your engine dyno tested, yet want to sound educated before talking the talk, ask the Dyno Shop, “What method do you use to calculate HP & Torque.” The answer should be SAE J1349. Although believe it or not, SAE J1349 isn’t the only Standard used worldwide, however it is the only standard used by US Auto Manufactures. So Really, why would you use anything else? If the Auto Manufacturer used J1349 to get your HP numbers, wouldn’t it make sense to use the same method of comparison? Using anything else is like comparing Apples to Oranges. So if your Dyno Shop Doesn’t in fact use J1349, ask them to also provide data using the J1349 Method. It should be as easy as the click of a mouse, AND a serious Dyno Shop will always post, “J1349” or their preferred method on your Dyno Sheet, and the method should appear somewhere on the display during testing.
Another important parameter you should know is Weather Correction. Weather correction is an integral part of the J1349 method, and in real life plays an enormous part in how well an engine performs. If you have ever raced consistently at a track or street at 3am, you know that cold Air always makes more power. Cold air is much more dense, which means more fuel can be added to the combustion process, and therefore more power is made, hopefully. For adjustability purposes, Dyno Manufacturers allow changes to be made to the parameter of weather correction so that Tuners CAN tune a car for altitude changes and Hot, Cold, or Humid climates. With that said, now you know that Tuners and Dyno Operators have the ability to change HP & Torque numbers based on weather correction. Well, I personally have never seen my Dyno’s software make a correction over 15% here in Wisconsin. So if I was to see a weather correction of 30% or more on a Dyno Print out, I would say that the Dyno Operator may have lied to you if the weather conditions that day are sunny and mild. If the Dyno Sheet doesn’t show Correction Percentages, ask to see them on the computer.
So there you have it! I have officially spilled the beans! The jig is up Shady Tuners. And so It is possible the Tuners around the world might have a riff with me now, but if the Tuner truly has integrity, would he seriously be upset that these secrets are know? That’s the way I see it anyways. Transparency. Integrity. Honesty. Need I say More?
The internet has some good info about tuning Ford and GM, but nothing truly complete. Mostly bits and pieces. And even then you have to wade through the troll comments and riff-raff. There is a lot of incomplete information out there, partial truths posted in Forums, and even worse, Shady Tuners selling mail order Tunes and offering really strange advice. Personally, I think that Mail order tuning should be outlawed.
The only time that I personally recommend Mail order tuning is Never. Well maybe If you’re in the situation where you know no tuners in the area and you have a new PCM installed, LS Swap has been completed, or a Cam upgrade, THEN I would say it would be appropriate. But only for the simple reason of getting the motor started so that the car can be shaken down, and made sure that it is in good running condition before a proper tune can begin.
When a new PCM is installed, the PCM may demand a “Relearn” process in order to promulgate new system parameters, security sequence, locate the crank trigger sensors, and many other hidden protocol. The relearn process takes about thirty minutes to perform manually in a vehicle, however it can be done using HP Tuners Software in minutes. The VATS/PATS Security Measures Installed by the Manufacturer to prevent Vehicle Theft can prevent engine start as well. A few key strokes on HP Tuners can fix that. Other times when a Cam has been upgraded, the Airflow numbers won’t match the actual demand of the engine, and thus rendering the engine unable to start. A good tuner will know what the right airflow numbers should be based on Cam Specs.
Because no two vehicles are the same, tuning takes precision. There are Mail Order Tuners that will take your money and send you back what I call a, “Cookie Cutter” Tune. One Size fits all. Maybe subtle changes based on specs you have given. But no Matter how good the Tuner is, there is no way he could possibly install an Accurate Tune for your specific vehicle. There is no way the Tuner could know the true demand of the engine without first harnessing the actual data from your specific vehicle. There will be many parameters that have error percentages above 5% or more. There are just too many variables to the equation for your vehicle. For instance, Parts, Tires, Air Filter, Fuel Filter, Vacuum Leaks, Altitude, Weather, Octane, and any number of changes you or your mechanic physically made to engine, all could have a noticeable impact on the tune of your Ride.
I can’t Stress enough that every vehicle NEEDS its own Custom Tune. I have fixed several mail order tunes in my time, and have heard of many people getting burned including myself before I started Tuning. The result of a mail order tune is an engine that doesn’t quite run right. Has a weird cough or hiccup at highway speed or some specific RPM, that only goes away after you floored it or completely let off the gas. And those problems are only if you get lucky. Other cases have resulted in Engine damage, PCM Damage, Long Wait times including shipping, Shipping Damage, No Start, you name it.
There is just too much to chance. Your investment is at serious risk of harm by relying on guesswork. Shots in the dark is the result of Mail Order Tuning. I personally feel it’s just bad business. So my advice is always find a professional tuner that can connect scanning equipment to your vehicle, collect and analyze real world data, and make changes based upon actual results. The outcome will make you much happier, save you money, and lower your exposure for serious headache and heartache…
Lately I have been getting a lot of questions on VE Tables and Base Maps. There isn’t really a whole lot of info out there about it, and most Tuners tend not to offer much information with customers. Probably because they don’t want to reveal their secrets of wizardry… Anyways, my brand of business has always been openness, fairness and honesty. Naturally I hope to add value to my services by sharing information with my clients, because I believe, an informed client is a happier client in the end.
So here goes: VE is an acronym for Volumetric Efficiency. The picture to the left shows the image of a VE Table (To the far left) and its associated Chart (To the right). The VE Table is a graphical depiction, made up of airflow numbers based upon the Axis of MAP and RPM sensor readings. So as the Engine cycles, the ECM calculates fueling measurements in a micro second, based upon airflow numbers from the VE table plus any other parameter set by the Factory Calibration. There are dozens of tables like the VE Table, all used to complete the matrix of a, “Tune.”
The Chart offers a visual diagram, or graphical interface for the Tuner to see the difference in plotted points within the VE Table. The Chart can sometimes be mistaken as, “The Map” or “Base Map” of the engine, if you will. Technically those are pretty loose terms, because a Tuner doesn’t tune a Map. The Tuner uses Data from a scanned log file of a running engine, and based upon the output of data harnessed from the engine, the VE Table is calibrated to meet the demand of the Engine. Using the term base map could mean anything, or any part of the Tune. So when I hear somebody talk about Tuning the Base Map, my first thought is, “Map of what?”
In my book there is no penalty for incorrect terminology, except two minutes for elbowing, “That’s a penalty!” However, other Tuners besides myself, may have dollar signs in their eyes when they hear you use such a vernacular. Using terms like, “ECM Calibration,” or if you own a GM, “PCM Tuning/Calibration,” would probably earn you more, “Street Cred” from a Tuner’s point of view.
The most important point here is to inform. Please don’t get me wrong that I have some hang-up about terminology, or you have to use the right words. No, I want my clients to be up to speed, wiser, and most importantly, informed. So the next time you got your leg up on a bumper, or serious lean on the tool box, you can talk the talk and “School” or “S-Cool” your Bros. Hope this helped…
That will help us both get right to the point!
w1710 Wisconsin Highway 16, Bangor, Wisconsin 54614, United States