DFWX, how can someone not take the DOT/EPA issues of the time into account? They were the reason for the 928 coming into existence! Porsche was worried that the 911 wouldn't meet emissions and safety standards and put the 928 into development, remember.
With regard to Porsche limiting production, bull-dinky. The car was built to replace the 911 as their bread-and-butter model - they wanted to sell as many as they could. As early as 1980, Porsche decided on a niche role for the 928 and kick-started development of the 911 again in earnest when they saw the 928 wouldn't sell well enough.
As far as the 928 being the flagship model and standard bearer, that can be argued. The 911 is what most people think of when they think Porsche, and the 911 turbo - as the ultimate 911 - is always seen as the ultimate Porsche - the "Porsche world supercar." The 928 showed up in
Scarface and
Risky Business, but that's in no small part due to the 911 turbo not being sold in the US at the time.
The 928's problems started from within - fact is, the Porsche family never liked it. They wanted the 911 to remain the top model since it was designed by Butzi and an evolution of the founder's 356 design. Making the 928 the top model turned representation of the Porsche name over to hired guns, and they weren't big on that idea. It's amazing the 928 is as good as it is, considering it's the red-headed step-child of the family. I find it amusing that the 996 is essentially a rear-engined 928 - a 4-valve/cylinder watercooled GT with Weissach suspension.
It's taken the 911 years to get to were the 928 started, and more years to catch up. Think what amazing cars they'd be making now if the 928 had replaced the 911 back in the 70s.
-E