That thing is fucking insanely fast too, it isn’t a muscle car, well it is in terms of power to weight ratio and ability to put wayyyyy too much power and torque into the rear wheels to be rational it is, but it isn’t an unwieldy tank like true american v8 muscle cars are.

McLaren started with the Grand National’s turbocharged and intercooled V-6, which already produced 245 horsepower (or more, but 245 is Buick’s modest claim), massaging it until 300 horses showed up on the dynamometer. The modifications are straightforward hot-rod stuff: ported and polished heads, a larger turbocharger with a ceramic turbine wheel, a dual exhaust system, a recalibrated PROM (programmable read-only memory) chip for the engine-control computer, and an insulated intercooler outlet tube, which keeps the temperature of the pressurized air from rising after it leaves the intercooler. Maximum boost has been increased to 16 psi, two more than the Grand National’s allotment, but a circuit in the engine-control computer still shuts off the fuel flow at 124 mph. The engine has enough grunt to push the GNX much faster, but Buick engineers feel the chassis wouldn’t tolerate much more speed without taking to the air like a Frisbee. The rest of the engine has been left untouched, a testament to Buick’s confidence in the soundness of the basic design.

Oh look damn, it is automatic, I guess it isn’t a real sports car right? Especially an automatic transmission from 1987? The thing is the way the turbocharger is tuned to SLAM torque into the wheels at low rpms a manual transmission clutch would be fucking toast wayyyy too quick. We are talking drag racing magnitudes of torque/acceleration potential, not normal race car amounts. The automatic transmission is a design choice to allow this thing to be a cruise missile especially at 90+mph.

0-60mph in ~5 seconds, ok fine, fast but nothing extraordinary especially nowadays, but the low 13 second quarter miles this thing can throw out in a near stock Buick GNX speaks to how fast this thing really is. The basic car is still just a buick regal, so yeah it doesn’t handle incredibly, but also it is a very straightforward platform to modify to make it handle better. Modified GNXs can do muchhhh quicker quarter mile times.

https://youtu.be/kIPU4TLDyRw