Accelerated Performance, in Ohio USA, managed to build a pioneering custom turbo kit for the FA20 engine of a Subaru BRZ. Pushing out a net 54.5 horsepower, this does not sound like a huge power gain from a turbo kit. The fact is that the high compression FA20 limits you from running a turbo kit with roughly not more than 4 psi. Still, such an achievement unlocks and further clears the road to discovering more ways to get power out of the high-compression direct-injection engine of the 86 & BRZ.
So why should be care then as it does not sound like a big deal judging the reported power gains? Well for starters, it is an achievement to install a first time custom turbo kit on that engine while big tuning houses and dealers are working with minimal updates about their version of forced induction applications.
This does pave the way for venturing further into modifying the engine for forced induction applications. All it takes it reducing the compression ratio to a conventional 9.5:1, in order to reliably & safely run 9 to 12 psi of boost. With the right engine internals, like piston seals, replaced along with ECU tuning; 250 up to 300 wheel-horsepower is not farfetched.
Now getting power out of a turbocharged FA20 is a logical solution for the following reasons:
1. Costs less than an full engine swap
2. Street legal, unlike a custom drive-train swap
We do have to be a little big compassionate about why Toyota & Subaru chose the FA20 from the first place, besides it lower centre of gravity & boxer performance, from the first place; we live in a world of tighter emissions and fuel economy figures. Yes it somehow puts limitations on the way we build our cars but this does not stop the aftermarket from finding their way around.[source: topspeed.com]