AVO has already confirmed that the FA20 engine can handle boost very reliably, not too much of course but it is very durable for FI application.
"If it wasn't for the fact that this FA20 motor is a completely different and modern design with an incredibly well made combustion chamber, we wouldn't even attempt to turbocharge these cars. But while many people associate it with the old EJ20 series motors from Subaru, there is absolutely no comparison besides the fact they are both boxer 4's made by Subaru. The entire design of the engine is different, especially the combustion chamber, which has been improved tremendously from anything previously made by Subaru.
Not only is the engine a major step up, the ECU on this car is also a great design, reacting incredibly fast to knock and adjusting parameters to compensate. This helps increase the reliability of the turbocharged motor. As is well known by now, this is also a direct injection motor, helping both power and gas mileage. We've seen mpg figures as good as stock on the freeway, probably better than stock as we were not exactly sitting on cruise control during our testing!
As you can see from the dyno chart, we saw 243whp (300 crank hp) and 201 ft/lbs of torque at 5-6 psi on 92 octane gas literally from a nearby Chevron gas station. This was with the stock airbox with an AVO high-flow panel filter installed, and a stock secondary cat in place. All these figures were reached on the stock fueling system as well!"
http://www.avoturboworld.com/avoshop...ual-p-191.html