Examining the Capable EA888 Evo4 Engine That Powers the Latest Golf GTI and Golf R

Initially designed by Audi’s engineering team, this gas-powered engine family has been in production for more than a decade. Countless versions with various displacements have been rolled out, all conceived with fuel-saving in mind.

Without a doubt, the most noteworthy of them all is the four-cylinder 2.0-liter TSI which in its most powerful variants does a great job of blending fuel economy with performance.

The latest iteration codenamed Evo4 has been conceived to provide even more power along with more-than-decent fuel consumption figures. Available in two output versions, it has been powering Volkswagen’s newest hot hatches, the Golf GTI and Golf R.

Built in a high-tech facility in Gyor, Hungary, the Evo4 can produce either 241 hp in the GTI or 315 hp in the R. According to WV, it can deliver an EPA-estimated 34 mpg (8.3 liters per 100 km) on the highway in the GTI or 30 mpg (9.4 liters per 100 km) in the all-wheel-drive Golf R when equipped with the DSG automatic.

Both variants employ very high static compression ratios for turbocharged units: 9.6:1 for the GTI and 9.3:1 for the Golf R. To increase durability, reliability, and ensure compatibility with four valves per cylinder, the double overhead camshafts are chain driven. The intake and exhaust cams feature continuously variable valve timing, while the exhaust cam adds variable valve lift and duration by using two distinctive camshaft lobe profiles.

Because these dual systems work together extremely fast, spent gases are evacuated quickly, allowing the turbocharger to spool very early which means that a healthy amount of torque can be delivered across a very wide rpm range. An additional benefit of the two systems is the ability to use longer final drive gearbox ratios, effectively reducing engine speed and consequently increasing fuel economy.

As soon as air is introduced into the Evo4, a specifically designed charge-motion flap fitted inside the intake manifold closes asymmetrically to induce a mixed swirling and tumbling flow motion in the air/fuel charge. While this primary benefits the air and fuel mixture, it also helps increase efficiency by allowing clean air to enter the combustion chamber, even at low engine speeds. When the speed rises, the flap will close, and maximum power can be delivered.

In both output versions, fuel is supplied to the injectors by an updated high-pressure direct-fuel-injection system at 5,076 psi (350 bar), compared to 2,900 psi (200 bar) in the EA888 Evo3 Golf GTI engine. In combination with the advanced turbocharger supplied by Continental, this contributes to the full availability of the unit’s torque potential at very low revs. Even before reaching peak torque, the Golf GTI makes 273 lb-ft (370 Nm) as low as 1,750 rpm, while the Golf R delivers 295 lb-ft (400 Nm) at only 2,000 rpm with DSG transmission.

Another interesting feature is the unique exhaust manifold design that is completely incorporated inside the cylinder head. This arrangement allows for quick warm-up and greater thermal efficiency of the exhaust stream. The gases exit the cylinder head outlets through twin channels via a point just short of the turbine wheel, allowing quick spool-up times and thus reducing turbo lag. Of course, this layout means that boost pressure builds up extremely fast so to regulate it, a highly sensitive electronic wastegate is fitted directly behind the turbine.

During its lifespan, the EA888 four-cylinder was known for many nagging issues like high oil consumption, failing thermostats, camshaft timing chain tensioners, or even turbos. We hope that these problems were addressed in the Evo4 because - as those who got to drive an Mk8 GTI or R can attest – this is a very capable engine that makes the cars very fun to drive, especially when paired with a manual. Speaking of which, North American enthusiasts are the only people who can enjoy the Golf R with a six-speed manual since elsewhere in the world, even in native Germany, the car is only available with a DSG.