What HP does your M3 put out? 370z is known to run very very rich and adding a few breathing bolt ons (intake and exhuast) has seen an increase of 20+HP in the States, putting it near 350HP
As for 350z vs 370z, I'll let you know around March time hopefully
Yep beavis is right, 343bhp. When BMW brought out the new M3 they jumped straight up from 343 to 400+, an increase of nearly 60 bhp is going to be very noticeable and makes it very attractive to E46 owners etc. I just feel that going from 313 to 329 to not exactly gonna have hordes of 350z owners dying to get into one. I appreciate its a more modern car and things like the rev matching gubbins and it being lighter and smaller will probably make more of an effect on performance but as they say, BHP sells cars......i think that the 370 is probably more attractive to non 350z owners as I can't get my head round why anyone would pay £15-£20k plus their zed for a 370z???
Yup you're right, its totally irrational to want to upgrade from a newer 350z to a 370z (ie 309BHP to 320BHP), and I dont think they will get many doing that. Older 350z, like mine, 280BHP to 330BHP, to easily ~350BHP with just an intake, that looks a whole load more attractive. If I had an 07+ 350z, it would be very hard to justify the jump. Everyone I have spoken to about the 370z says it drives much better than a 350z and the interior is much much better too. As you say, most customers will be non 350z owners, people who were looking at Porsche for example, with a few older 350z owners in for it too. All dealers I have spoken to about it say they have had quite a few 350z PX against them, but you take that with a pinch of salt when they are after your business.
As for the GTR, we all know its the running costs that prices most of us out of getting one