So, a friend approached me (a non-car guy, in that he likes cars, but isn’t a change-all-the-things enthusiast) about whether a chip can really add 75hp/100lb.ft. For the record, he has a ’17 VW 1.8T Golf SportWagen with 4motion, and a DCT. It is, in fact, a great little package. I almost bought one myself, but the wife didn’t love it as much as I did.
This one is text-heavy. Be aware!
He was, as you’d expect, curious (because more power, easy like) but also skeptical (because more power, easy like).
Here’s what I sent him*:
Tuning is the real deal. The manufacturer is 100% concerned about vehicle longevity, and fuel economy (class dependent, of course). So, when they build an engine, they build it with a particular life span in mind, with an eye to the warranty period. Mitsubishi and Hyundai both offer ten year warranties (well, Hyundai does in the states, and we get the exact same product, so while we only get a five year, we’re getting build that has ten year in mind).
At the same time, power comes from efficiency. So, they’re also balancing a level of power from an engine that makes the consumer happy, with fuel economy that makes the consumer happy, with longevity that makes the consumer happy, and keeps the manufacturer from having to pay for repairs (and a happy consumer buys from that manufacturer again).
Why the preamble? Well, it’s important. A tune, or chip, or reprogramming the ECU alone, for more power is a viable option for any engine. You’ll see a lot more response to a tune from a turbo engine, because that’s just life with forced induction. More air in = good. To a point.
In the case of your 170hp/199lb.ft VW 1.8L turbo, I’d guess that 75hp/100lb.ft at the crank is not out of the realm of possibility. It’s likely advertising-on-best-case (so, upgraded intercooler, intake, exhaust, probably no more catalytic converter, and maybe larger fuel injectors) but viable. Realistically, that engine is putting (stock) around 150hp/170lbft to the wheels. So, just a tune to optimize that delivery of power could put a fairly easy 200hp/250lb.ft to the wheels. APR (a respected VW tuner) offers a tune with “up to 234hp/273lb.ft of torque” with no bolt-ons.
How’s it doing that? Well, to get more technical than they do in their link, they’re re calibrating fuel and air delivery, specifically boost levels, throttle input control, and a number of other things.
APR also advertises with a “limited warranty”.
And that’s where we get to the details, the real meat of the matter.
As soon as you tune your vehicle’s ECU, you can kiss your factory engine warranty goodbye. There’s no such thing as a “voided” warranty, but any claim for a system affected by the ECU tune? You can expect to have that claim denied. So, turbo lets go at 30,000km because you’re pushing 19PSI rather than 14PSI (numbers made up, I’ve not done research as to where the 1.8T stands on those levels)? Well, guess what? You went outside manufacturer spec, and they’re not going to pay for repairing that. Windowed the block because it got lean (too little fuel) at high RPM? Denied claim. Likely as deep as transmission problems due to 35% more torque than the factory planned on going through the drive train consistently? Claim denied on drive shafts, half shafts, transmission, etc.
So, when I told him “Yes if, and no, but…” I meant it. If you’re going to tune, you have to know what you’re getting into. A manufacturer could provide the power levels a tune does. But they’ll see more repairs, earlier (ie. In warranty, at their cost) so they don’t. They have the drive train set up to provide longevity, economy, and power. When you tune, you give up at least two of those. You’re tuning for power, so you’re giving up longevity, and possibly economy.
As an enthusiast, I can totally see the allure of a reputable tuner putting more power into your car – I’ve seen perfectly reliable tuned-up cars in the last ten years. But I’ve also seen GIMME THE BIG GUNS tuning that blows up, just to get “numbers”. If you’re going to get your car tuned, especially your new, warrantied, daily driver, then know what’s safe, and spend the extra on a reputable tuner.
And know that it’s a slippery, slippery slope into modifying. I mean, what’s another fifteen hundred on exhaust and intake, right?
Stuff with pictures next time. Promise.
*Turns out, I got a look at what I wrote, and realized it was too much to send over FB messenger. So I just sent him the link to this. I always go too far.