I've owned a GN for the last 10 years. Nice shape, but not like the one Tony posted. The car is made for cruising or dragging although some guys have modded them and are very competitive at autoX.
Bolting on a few parts with a stock block, I'm running 11.9's 1/4 mile. This is fully loaded with A/C and electric everything. For the track I change chips, race gas (cp16 118 leaded octane) produces 26 psi boost, and drag radials. Any faster and I'm forced to install a cage, so I'm pretty much done working on performance for now.
The Hurst Lightning Rods come from the mid 80's Hurst Olds.
Here's stats from Car and Driver. The 0-60 times are respectable at 4.9. I believe 4.7 for the GNX is very probable.