[DGthe3]

This is the reason also the reason why GM's specific output is so low, so that you have lots of room to build. Also, its why the chevy small block is such a legend. Its possibly the least expensive way to get a car with 500 hp.

As Dragoneye mentioned, there is also the SAE system of measuring power vs the regular way. Basically, the SAE system gives more accurate results because it uses warmer air at a slightly lower ambient pressure than the STP (Standard Temperature and Pressure) protocol that magazines tend to use. Therefore, the SAE test will give less power since the cars have less oxygen to burn, generally they give about 5% lower ratings from what I've read. But its closer to the real world, thats the official reason why they use it. However, it also means that the 430 hp LS3 is making something in the 450 range if it were to use the STP method. Also, the L76 would be around 380 hp.