OK, normally I keep this show family-friendly but I’m so passionate about this that I’m just going to let it flow and be myself. I’m going to address something that Paul Yaw from ID calls the “Bullshit Epidemic” – firstly I’m going to address a very silly article that’s been shared recently and then I’m going to address the general problem.
In this industry, my fight is not against our competitors; my fight is against ignorance and misinformation. The majority of our technical support load is not people wanting to know how to use our products; it’s telling people about the car in front of them. If more tuners knew more about tuning, EFI and diagnosis then our lives (us and our competitors) would be a lot easier, tuners’ lives would be easier and customers would be more satisfied. This is why in our tech videos I don’t just talk about what the ECU does, I also talk about what’s actually happening in the real world because, damn it, it’s important.
So in this fight, my enemy is people who spread misinformation. I’m not going to give my enemy free publicity by sharing a link to the article, but it’s an article saying you should never “lug” your engine, that is, visit the low RPM / high load cells, because it will cause preignition and cause engine damage. It’s so silly I shouldn’t even have to address this, but unfortunately some people have been sharing it, even one tuner proudly declaring that he starts his ramp runs at 4000 RPM to avoid this problem, so unfortunately my enemy has created work for me here.
Firstly, the burden of proof is on the one making the claim. You can’t say “you will get preignition” without justifying it. The fact that it’s illogical and unexpected raises the bar of proof even further – as Carl Sagan said, extraordinary claims require extraordinary evidence. In the video they describe the causes of pre-ignition, which is that you need some kind of hot spot above the ignition temperature of the fuel / air mixture, but they don’t say how likely this is to occur, or why it’s more common at low RPM than high RPM. News flash, at the same manifold pressure or same torque, everything in the engine is hotter at high RPM. Power is torque times speed; the engine’s thermal efficiency doesn’t change by a lot so at higher RPM you have more heat generated; internal components become hotter because they have less time betwen ignition events to cool down and the ignition events are occurring more often. So that’s an obvious problem with the explanation.
A second obvious problem with the explanation is that an engine is less efficient at full load than part load. Notice they don’t say by how much. The answer is that they haven’t measured it; engines are MORE efficient at full load than part load because the parasitic losses in the engine to drive the valve train, overcome friction and so on are basically fixed. This is why an engine at 1 bar boost usually makes more than double the torque of the same engine with no boost. If you don’t believe me, try it; it’s an easy test; your ECU should be able to tell you your fuel usage rate, or you can work it out pretty easily, and on the dyno you can see the power produced in the steady state.
The third obvious problem is that the symptoms of pre-ignition are basically the same as knocking, but as he correctly said in the video, you can’t fix it with ignition timing because it happens before the spark. This is all fine, but I can tell you that pre-ignition must be VERY rare because we get all kinds of questions from tuners, and after selling thousands of ECUs I’ve only heard a tuner say that they had knock that they wouldn’t fix with spark timing once, and in that case his ignition outputs were configured incorrectly so they were firing at the wrong angles anyway. I know that pre-ignition and knock are not the same thing but if the symptoms are the same then at least some percentage of tuners would diagnose pre-ignition as knock and I can tell you that I’ve never heard of this happening.
Now of course it would happen if you have very high compression, eg 18:1, and really low octane fuel, eg Diesel, but that’s not we’re talking about. And for the same reason it might be more common in direct injected petrol engines which often run much higher compression ratios than port injected engines.
You can also look at it from an economic perspective. Would auto manufacturers really design an engine so that you could make it pre-ignite and destroy itself just with your driving style? And for that matter, once you tune an engine properly, does it knock at low RPM, wide open throttle? I’ve never had one that I couldn’t tune correctly so that it didn’t knock.
Now spreading this kind of bullshit is really dangerous for several reasons. Firstly, it adds to the level of bullshit in the world, and it creates work for me to fight against it. Secondly it’s encouraging people to just believe stuff instead of thinking for themselves – because many of the points made in the video don’t pass a few seconds of critical thought. Thirdly, imagine if some tuner did hear this and only tuned from 4000 RPM upwards; how would they know that the tune was correct at the low RPM full load condition? It could be pinging its nuts off and they wouldn’t know because they didn’t bother to tune it there.
Now let’s look at the general problem, the bullshit epidemic as Paul Yaw called it. I encourage you to do a Youtube search for Karl Pilkington, Bullshit Man, because this guy would be my superhero. I first became aware of this when I was young and stupid, and in those days it was email forwards (before social media). Someone sent me a forwarded email about a date rape drug which left the victim infertile and I thought wow, that’s scary, I should let people know about it. Someone smarter than I replied to everyone and said Andy, stop sharing scary bullshit; this isn’t real, you’re just spreading fear, 30 seconds of googling would have told you this. After this I became really interested in urban myths, why they spread and so on; I knew almost all the myths on the Snopes website and found them fascinating.
These days it’s Facebook shares rather than email forwards but the formula remains the same. There are a few types of these myths that get shared – some of them happen to be true but whether they are true or not has no effect on whether they get shared.
There’s the superstitious bullshit, like this 31-day month is the only one which has a Saturday, Sunday, Monday occur 5 times in it and this only happens every 843 years so make a wish.
There’s the fear mongering, hypodermic needles in petrol pump handles, that sort of thing. Yes it’s a good idea to check where you’re putting your hands but is it true?
There’s the “glurge”, dog walks back into burning building to save his owner, that sort of thing.
There’s the “fantasy”, where someone in the story acts out a fantasy that many of us have had (the barometer physics question, the stories about the hot 25 year old female teacher who bonks a 17 year old schoolboy, that sort of thing)
And sometimes there are stories just shared so that the person who reads it can feel superior to others now that they think they know something that others don’t. Here’s how to recognise a heart attack, this natural ingredient cures cancer and creates world peace but the FDA have outlawed it, etc – and unfortunately this is totally the case with this piece.
There are many ways to tell if a claim is bullshit or not, and if you care about this then you can join a skeptics group on Facebook or something like that.
The first one I like to use is, does it actually make sense. Obviously many articles will get shared BECAUSE they have a conclusion that’s counter-intuitive but in many cases your intuition is right.
If it doesn’t make sense, then have they backed up their claim, and also why the common sense understanding is wrong? If not, then it’s probably because they can’t back up the claim, not because they’re too lazy.
Are there numbers involved? Mathematics is the language of nature. A 2 kg ball has twice as much gravitational attraction to the earth as a 1 kg ball, and it’s twice as hard to move. If someone has an explanation of a technical phenomenon with no numbers involved then be very wary. Similarly with medical claims – sometimes you see that something is claimed to be poisonous or carcinogenic – but it’s the dose that makes the poison. Maybe it’s poisonous if you take 10 grams of it at once but in small doses there are no ill effects at all. Paracetamol is actually poisonous but the doses we take it in medication are such that our liver can process it before it’s a problem – unless you overdose of course.
Do they explain the conditions? For example if you were talking about pre-ignition as a problem, and requiring a hot spot to initiate combustion then a sensible discussion should start with what the temperature needs to be, and what conditions need to be met to achieve this for example octane of fuel, compression ratio, coolant temperature, boost pressure. Or at least one example where they observed it!
Can they explain the mechanism? If they can’t explain the mechanism, then it’s not good enough to say “we don’t know why this is true, but it is” because if they don’t know how it works, they don’t know what it depends on. Maybe this pre-ignition thing is only true on certain engines (if it’s true at all, that is).
Similarly, the more general the claim, the less likely it is to be true. You’ll notice that experts are very measured in their claims; they put a lot of qualifications around their predictions, state the conditions and assumptions. Novices, or people trying to sell something often give very broad claims, such as “never do this, you’ll damage your engine”. The bigger the claim, the more proof is required, and generally the less is offered.
Lastly, at the risk of creating an ad hominem attack, you can research the person making the claim. If someone is claiming some kind of magical cure for cancer, and you go to their website and they’re also promoting other kinds of quackery then it’s probably also bullshit. It is true that an argument should be able to stand or fall on its own merits, regardless of who promotes the argument, but the fact unfortunately is that there’s so much bullshit around that sometimes it’s in our interest to take some shortcuts.
This last point also means that if you value your own credibility, you won’t be sharing bullshit. Including that stupid thing that people say on FB where they’re claiming ownership of what they post on FB, with “better safe than sorry” – it is possible to be both.
So for goodness sake, please use your brain before sharing shit. There’s already so much bullshit around and it’s really unethical to force others to sift through it.