From Saabscene:
Joined Jun 17, 2009
1,316 Posts
#3 · Jul 13, 2012
On the contrary, there are many thousands of Vectras with the B207 engine, and Vauxhall Signums as well (including mine). Vauxhall refer to the B207 as the Z20NET.
However, the issue is not one of bore differences or engine compatibility. Differences in bore size can be fixed using a reducer pipe. As for engine compatibility, many Vectra Z19DTH owners often fit an exhaust from a B207-engined Vectra, so that's not the problem. The problem lies in the small differences to the floorpan between the 9-3 and the Vectra. The Vectra has a one inch longer wheelbase, hence the centre pipe will be a different length, and the rear overhang is a different length hence the tail pipe will not sit in the correct position. The biggest problem is that the back box on the 9-3 is mounted at a different angle to how it is on the Vectra hatchback, hence the mounting points will be in completely the wrong position.
Exhausts are generally only compatible between cars with the same body. The 9-3, the Vectra hatch, the Vectra estate and the Signum all share the same chassis, but small differences in the wheelbase and rear overhang mean exhausts can't be swapped between them.