Well it all depends what the OP wants, if he wants a V8 all motor then thats good, but if he wants turbo an SR20 has been proven for many years even decades or even an RB26 but it may be too big.
From a price point of view, an SR20 you can probably pick up for $2500 while pistons and rods for the GC are about $1400 alone as we've seen. But then you would have to custom fab motormounts, driveshaft, rewire the entire car just to get simple things like lights and windows to work even on a standalone.
I rather have an RB26 any day over this 4B11, but then again money and down time is a big issue. To go fast with this OEM motor you are looking to spend a good amount of money anyway, just look at the OEM intake manifold towards the back of the car, notice that HUGE hole making you lose lots of air volume because of a bolt? 330cc (im guessing) injectors from factory, weak connecting rods? Wrong studs on the turbo and exhaust manifold, I mean how much more proof do we need that Hyundai could go any cheaper by not researching to make this car have more potential like the REAL 4B11, the EJ25T (altho pistons are an issue),the SR20, or any other 4 cyl that can hold almost 400whp (some even more) stock? The proof has been here for decades, but I guess keeping the cost down and neglecting the 2.0T has been their goal.
Any commercial you see of the GC is of the V6 and its "GLORIOUS" 306hp coming around a turn sideways, wow big freakin deal, my 08 STi with bolt ons, stock turbo, and injectors put down 317awhp and 375awtq and that is with a huge powertrain loss compared to a rwd or fwd car.
Sorry I've just been a little bitter about the 4B11... :rofl:
/rant