It's already been said.... but, definitely do some research. That's a hot-air car for intercooled money. The differences are far beyond just the intercooler, though both 3.8 liters, the engines aren't the same. Intercooled cars are far more desirable, with the 1987 GN making the most stock horsepower and torque, and the 1986 GN having many less units in the production run. Is there a reason you are only after a Grand National? As Charles mentioned, there are other options. The '86 T-Type/ '87 Turbo T cars are mechanically the same as the GN, but with far more color and interior options. If the $16k car in that ad fits your budget, you should be looking at intercooled cars for sure.