It depends on how you describe "souping up"...
If you bolt on an intake, overbored throttlebody, reworked intake manifold, strap on a tuned header and full exhaust, throw in a cam or two, an upgraded ECU, a new ignition system, a 4-puck racing clutch, and have the cylinder head ported and polished... Well then, you still wouldn't blow a cylinder.
If you strap on a 250HP shot of nitrous, you'll forcefully shave the ringlands off most (or all) of your pistons. This would be a "Bad Thing"(TM)
If you want this car to produce any more than about 225 horsepower at the tires (which given the losses of this transmission, means your engine is building between 240 and 250HP) the internal motor components will need work.
Pistons are the first thing to die in this motor, mostly due to detonation from hotspots from the casting errors in the crown. A set of JE dished pistons can be purchased for about $600, Endyn is also making boost-dependant pistons for less money, however they're not finished and they DO require aftermarket rods.
After about 300HP at the tires, the stock connecting rods will fatigue. Either torsional force will create stress cracks right below the pin bushing, tensile loads will create a longitudinal crack down the center, or simply too much power can bend them in the middle. Crower will build a set of Tiburon / Elantra 2.0L rods for $667 plus shipping.
The very bottom end of the motor is nearly indestructable at currently-attainable power levels. The crankshaft is forged billet steel, and we've never recorded a crank failure at engine output as high as 575HP; the crank main bearings don't seem to complain either although wear rates are a bit faster at that level. The crank main caps are also girdled stock, so vibration is minimal and as such main bearings still live a long life at high RPM's.
The other weak spot in these motors is the HLA system in the cylinder head. Due to the nature of micro-hydraulics, they are very fragile when dealing with high RPM's. Without having the entire head re-cast with solid lifters and appropriate supporting equipment, the redline of this motor likely shouldn't exceed 8000 RPM's if you want any of the HLA's to survive.
-Red-
