You've probably heard that it's possible to boost your engine for very little money. And you've probably heard the opposite, that miracles don't exist and that boosting an engine for little money is impossible. Which of the two things is true? Well, both. And as always, we're going to give you the reasons and the arguments. Because it is possible to gain some power from our engine or improve the performance of our car for little money, without having to open the engine and complicate our lives. We have to start from a base: Car manufacturers are not stupid and if making more powerful engines were possible, they would make them. But a street car, for an engineer, is an exercise in balance and compromise: It must consume little, have very low emissions, be reliable, last many kilometres, give good power and, above all, be affordable and cheap to manufacture. And this is where we can act. Let me explain: Maybe we don't need so much reliability or we don't mind spending a little more in exchange for more power. Because, what is the duration of an engine that a manufacturer considers reasonable? Well, I'll tell you: A modern engine is "eternal"... So it's true that miracles don't exist, but it is possible to achieve significantly improved performance without spending a lot of money. We have set ourselves a limit: Things that can be done without opening the engine. And I'll tell you something in advance, the best results are achieved by combining more than one solution. One last "warning to sailors": Many of these changes make us lose the warranty. 1 First, tune up. Before getting into trouble, especially if the car is used or has miles, do a thorough tune up, with filter changes, spark plugs, valve adjustment and a general check to make sure that neither the intake nor the exhaust have leaks... This really benefits everything, both power and consumption, emissions and reliability. And maybe you do it and discover that you don't need anything else. 2 Intake kit. Back to the compromises: A manufacturer makes a car thinking that if its owner has to travel a few kilometers on a dusty road to get home, the car will not break down. But we never leave the asphalt… so to speak. Production cars have very dense filters and there is something to be gained here. 3 Sports exhaust. You can change the entire exhaust or just a part. In classic cars from the “pre-catalytic” era we can put a silencer that retains less and sounds a little better - mind you, I say better and not more. But in more modern cars we can also put higher performance manifolds. 4 Raise the RPM limit. This modification does not make the car give more horsepower but it does make us take better advantage of it… It is much cheaper than reprogramming. 5 Reprogramming. Reprogramming or “repro” is very fashionable and is another “miracle” solution. But no, there are no miracles. Depending on whether the engine is diesel or petrol, turbo or naturally aspirated, we can gain up to 10 percent of power, which is no small thing. Be careful! I say “up to” meaning that is the maximum. If they promise you more, be wary. 6 EGR valve. Another panacea. I will tell you one thing in advance: Never, but never, no matter what they tell you, will removing the EGR valve make the engine have more maximum power. Why? For the simple reason that at high revs and with the accelerator fully open the EGR valve does not work. So don’t be fooled. 7 Turbo pressure. This is very simple: If we let the turbo put in more pressure, the engine increases power… it will consume a little more and if we do it too much, it can even break down. But increasing the boost pressure a little can be a good option. 8 Oil. Can an oil make my engine run better? Yes, for two reasons: It keeps the engine in good condition and has the right fluidity at all times. 9 Additives. There are many types of additives. Those that increase the cetane index can improve power somewhat. Those that clean the injectors can be recommended for use from time to time. But the best additive is a good fuel. 10 Tires. No, changing tires is not going to make our engine more powerful… but it will make it seem that way. Excessively wide tires are a hindrance, but the option of putting tires with a slightly smaller diameter also works. And we come to the end. To my final advice. If you have a car that is already old or a classic, this type of thing may interest you. But if you have a modern car, my advice is clear and it is the one I follow: A careful tune-up with top quality oils. And that's it. Car of the day I told in Episode 2 of “All the cars I’ve owned” that I bought a 2-door Seat 850 Special from a friend of mine, as a “tribute” to my first car, a Normal Seat 850.