I really don't follow that logic, although it makes for a nice story...
GM certainly would have known before producing the GN that it would outperform the Vette, so I don't see how that would have killed it. Complaints from Corvette owners? Not likely, I don't think many Corvette owners would take the time to write the factory over such a thing.
No, I think it was just not a good seller or money-maker, and since automaking is (theoretically) a for-profit business, it would make sense to either kill the car or develop it. If, in fact, it were on a platform not so economically feasible to develop, then that's it for the car.
I suspect it was just the wrong environmental, economic and technical time for the car.
GM probably had some sort of multi-year product changeover with switches to FWD midsize cars (for manufacturing and mpg reasons I suppose). Cars like the GN, as rather limited runs, probably have little or no effect on decision making at a division level.
It also wouldn't suprise me if all of those turbo cars (GN / Typhoon / Syclone) had warranty issues that make them unattractive as money makers (aside from the economy of scale issues).
I do think that the Sy/Ty cars are *way* more interesting than a GN/GNX. I think of Regals as just another poorly built RWD midsize with lineage back to the '64 Chevelle while the GMCs are actually kind of original in design and execution. Wasn't it C&D that called the Turbo Regal an 'engine in search of a car'? Hey, I know, perfect for that Spitfire you've got in the backyard.
Everything in 1988 was going front wheel drive thats why they stopped producing the GN.
Also the interior was awful. It was hard to look at, and was not sporty at all.
The 3.8L in the arly eighties produced as little as 105 hp ao Buick came out with a 4.1L version for a while.
For those of you who have driven one, how was the low end torque? I would imagine that there wasn't much.
...but I've owned three General Motors G-bodies: a 1980 Malibu 229, a 1982 Cutlass Supreme 231, and a 1986 Monte Carlo 305. While the G- (A- from '78-81, it was renamed G- for '82) may have had its flaws, I think it was still very competent compared to what was available for competition at the time. Remember that while GM was sticking 110 hp or so 3.8's in its cars, Ford was sticking weak inline 6'es and even 4-cylinders in its competing models. Finally they threw in a 232, but it only put out about 120 hp. And Chrysler's cars were so heavy that you needed a 318 just to get about the performance of a GM G-body with a V-6!
The main problem with the Grand National's interior was that it shared it with the lesser Regal, which was designed to appeal to a more mature buyer. As a result, you could get a gauge package on a Monte/Malibu, LeMans/Bonneville G/Grand Prix, and Cutlass, but I don't think you could get one on a Grand National. They had a little tach added on as an afterthought, but I don't think you could get a temp gauge, oil pressure, amps, or a speedo above 85 mph. But otherwise, these things were comfortable, quiet, roomy cruisers.
As for low-end torque, I don't know where the turbo 231 peaked out, but the normally-aspirated 231, which only had a 2-bbl carb on the G-body, peaked out at 190 ft-lb1600 rpm. It wasn't much from 0-60, but punch it while you're loafing along at 30-50, and it'll still give ya enough of a kick to surprise you!
I think it looks the same in terms of complexity. They both look like the inside of biology class cats. I suppose that is what is going on generally, car designers are moving, bit by bit, towards building life forms rather than simple machines. As you see more and more redundancy, self-healing mechanisms, and generally complex behaviors, we'll move away from mechanisms and more towards simple animals. Add breeding behavior to the mix, and, voila!, Chevy Suburban + Trabant = Pontiac Aztek.
Yes, the engine compartment is pretty messy. It looks kind of home-made compared to many current cars' engine compartments. Maybe some ABS plastic engine covers would have helped the presentation for marketing.