Unless you’ve been hiding under a rock for the past decade or so, you may have come across the idea of tuning cars by stages- although over here it most commonly applies to Volkswagen and Audi models. The idea of stage tuning goes back a pretty long way, and even JDM specialists like Skunk2 have made performance products that go by stage, although the most prevailing use of the term is by tuning companies that specialise in continental cars.
While different tuning companies may quote different power outputs for each “stage” of tuning, the variation is roughly 10-20 PS, and is usually attributed to how “conservative” the tune is. Each stage of tune (or map) extracts more power by increasing the amount of boost, increasing the amount of fuel, and advancing or retarding the timing throughout the rpm range. The stages themselves are fairly loosely defined, although the trend is this:
Stage 1 – an ECU remap, recommended with a larger intake
Stage 2 – an ECU remap with a larger downpipe, highly recommended with a more effective intercooler and larger intake
Stage 3 – commonly a larger or modified turbo, with an ECU remap
You can see that at each point the ECU is remapped (or tuned) to take advantage of the better airflow as a result of the parts change, whether it’s more air in via a better intake, quicker air out via a free-flowing down pipe, or just more boost in general with a larger turbo. The main idea is that in stock form, the engines are restricted by the intake/exhaust/intercooler/turbo size, and working your way up through the stages gives you a logical path for improving performance. Running a larger turbo with the stock intake and exhaust restrictions won't give you nearly as much power as if you had the right supporting modifications. There are more stages beyond this, but they usually push the engines so hard that internal work is required and drivetrain life is significantly shortened.
For a lot of enthusiasts who have been modifying engines on their own, the idea of stages may seem a little odd. Traditionally an engine build requires you to think about the kind of power output you want, then work backwards to figure out what kind of compression ratio and cam duration you would need, and so on and so forth. It’s part art and part science, and while the internet and forums are a great resource for you to find out how much an engine can take, there’s still a fair amount of calculation and a hint of guess work to get everything working properly.
But modern engines- more specifically, modern force inducted engines- usually come with more than enough strength and headroom for extra power built in from factory. As an example, the EA888 (the most current turbo 2.0-litre engine shared by Volkswagen and Audi) has more than enough potential for higher power outputs. A bigger intake and exhaust, an intercooler upgrade, and a bit of reprogramming can see power rising from a fairly standard 220 PS to well over 300 PS- and all without having to open up the engine.
The other benefit of stage tuning is that all of the calculation and the guesswork has been taken out of the equation. These tuning companies based in Europe and America put their test vehicles through massive amounts of research and development, testing their tunes over thousands and thousands of kilometres to make sure that they don’t cause complications in the long run. When they are almost absolutely certain that their tunes produce the required results without compromising driveability, only then are they willing to put their names on it and put it out on the market.
From a consumer perspective, it makes a lot more sense to go stage by stage. It’s far easier to tell a tuner that you want a “Stage 1” tune for your car, than it is to tell them you want X amount more horsepower or you want it to be “faster” in general. It also standardizes pricing, making it easier for tuners to give an estimate on how much it’s going to cost an owner to push the performance of their car. It has benefits at both ends, and it provides owners with a fairly predictable result- even if it means your Golf GTI is near identical to a hundred other Golf GTIs.
What’s the downside to all of this? In a sense it takes some of the skill out of extracting performance from an engine, since all that’s involved is swapping a component or two and overwriting an ECU with a pre-written map. Some tuners may go the extra mile to make sure the car is performing properly after the remap (especially with our hot, humid conditions), but most are perfectly content to let you loose and let the systems handle any complications.
There’s also a lack of creativity, or rather a lack of opportunity to discover creative solutions. When you look at some of the performance builds based on engines from the 1990s or earlier, you get a sense of how tuning concepts and ideology have changed over time. You can also see some novel solutions to tricky problems- things that you generally don’t see happen when you’re dealing with pre-written ECU maps and engines with plenty of potential from factory.
And perhaps this is why there are those who get a little salty whenever the word “stage” is mentioned. It’s difficult to acknowledge that the cookie cutter approach to tuning is a much more popular method; customers are more willing to go for a predictable result than to venture forth into the unknown with a big ol’ Garrett turbocharger, some larger injectors, and a prayer or two. There are those who still push the limits of these Volkswagen and Audi engines in the more traditional sense, but they are few and far between.
This is in no way meant to disrespect those who specialize in remaps and the like. They provide a good service like any other, and some of the local outfits like ATM Performance will also give you great support after installation- generally making sure that your car runs the way it should. The only thing to keep in mind is that increasing the power output of your engine will shorten its lifespan, no matter how you achieve it.
The engine might not die in the next week, or next month, or next year- but these engines are designed to last a solid 10 years without a rebuild, and subjecting them to more stress takes a number of years off of their lifespan. While most traditional tuners seem to understand this idea well, it is not something commonly understood among those who get their cars remapped- but of course if you’re going to sell your car within 5 years, then it isn’t exactly a problem that concerns you.