The normally aspirated 350 is certified as "spin resistant", so the FAA didn't require spin testing beyond its ability to keep from spinning with the controls crossed.  But the turbocharged 400 is certified as "spin recoverable".  Due to the larger operating envelope, up to FL250, the FAA required the higher standard.  So Lancair/Columbia had a spin test program that lasted almost a year, with several different modifications being tested.  They were taking that Columbia deeper and deeper into stalls, forcing spins, letting them get well developed, that's why they had the spin chute in the first place.  They planned on taking it into an unrecoverable spin, or at least the were prepared for that happening. The spin chute is to get the aircraft out of the spin, cut it loose and fly home and change your underwear!

 

As to the differences between exact models of certified aircraft, the manufacturers have to get a production certificate from the FAA.  They have to show the production and QA procedures and convince the FAA that the production aircraft will perform the same as the aircraft that earned the type certificate.  There are fairly tight tolerances defined by the various factories.  But we all know not every plane is EXACTLY the same.

 

Mike Easley

Still in the paint shop!