How Nissan's SR20DET Engine Packs Such A Powerful Punch
The Nissan SR20DET is one of the Japanese four-cylinder engines most beloved by tuners. It is the turbocharged version of the popular SR20 2-liter engine, which powered cars like the Nissan S13, S14, and S15 Silvia, as well as the 180SX, although it also powered a front-wheel drive performance Nissan, the Pulsar GTI-R from 1990 (pictured), one of the coolest JDM cars worth importing.
It debuted in the 1988 Nissan S13, and it made 200 horsepower. Power was upped to 217 horsepower in the 1994 – 1998 S14 model and again to 247 horsepower in 1999 when the S15 was introduced. The increase in power came courtesy of a new and larger turbocharger, as well as technological advancements such as variable valve timing, which not only allowed for more power at the top end but also better torque distribution across the rev range.
Thanks to its dual overhead camshaft design, the SR20DET had four valves per cylinder (two for intake and two for exhaust), which, in combination with an advanced engine management system, allowed for more precise control of the fuel-air mixture. This not only made the engine run cleaner, but it also helped with responsiveness and power delivery, especially at lower rpm.
An aluminum cylinder head helped reduce its weight and also aided with heat dissipation. It had strong stock internals, and it was light and compact. Its small size made it a viable option to swap one into many different vehicles (even non-Nissans), and the fact that it was turbocharged from the factory made it easier to extract power without having to add costly aftermarket parts.
An SR20DET Can Make a Lot of Power
Even though the modding scene for the SR20DET is not quite as large as the ones for the six-cylinder RB25DET and RB26DET from the Nissan Skyline, the aftermarket parts scene is still pretty big, especially if you don't limit yourself to just looking for components locally. Since SR20-powered vehicles were far more common in their native Japan than anywhere else in the world, if you want the best and most extreme mods, it is there that you have to look.
Tuners could double an SR20DET's stock power output on an untouched bottom end without the need for upgraded internals, extracting close to 400 horsepower out of it relatively easily. All you had to do was replace the stock turbocharger with a bigger one and upgrade the fuel system so that it could keep up.
Aside from upgrading the turbocharger, which is the most common power-boosting mod for this engine, if you're really serious about extracting more power, then it will need forged internals. They won't break under the stress of hundreds more horsepower than stock, and they will give you peace of mind to add even more power-boosting mods into the mix.
Chances are, if you put beefed-up internals in this engine, you will already have done the intake and exhaust. Adding a custom boost controller is also recommended, as is installing stronger valve springs, which are vital if you want to prevent valve float at high rpm in an engine that's already running a lot more horsepower than stock. You can get up to 700 horsepower out of this engine, although probably only the block will remain stock in something that highly strung.