Just paid a deposit on the last red 100th Anniversary edition remaining! Keen to add an induction kit and maybe a (subtle) exhaust from the get go. More to enhance that beautiful sound than for performance. Any ideas, recommendations, comments?
I suppose it depends how far you wish to go, and at what expense.
A simple drop-in replacement air filter can increase induction roar slightly. I have an Autodelta (UK) foam filter; can be cleaned and re-used. Didn't make much difference noise-wise, but probably because my exhaust is significantly louder than stock. No seat-of-pants performance benefit (for better or worse). Can buy directly from the UK.
(http://pic20.picturetrail.com/VOL97/467659/22016129/363299075.jpg)
K&N and BMC also offer drop-in replacements.
Replacing the plastic induction pipe between the AFM and throttle body is a popular upgrade. Partly cosmetic, partly for induction sound. Some people report a drop in low-end torque, but I did not notice this. Autodelta offer a carbon fibre version; some people have been unhappy with the less-than-perfectly smooth internals, which can have rough carbon fibre strands, which won't help airflow.
I have a custom polished stainless steel pipe. Some exhaust/metal fabricators could do the same. I purchased mine through a fellow Alfista; his mate did a custom batch.
(http://pic20.picturetrail.com/VOL97/467659/22016129/377217002.jpg)
If you aren't fussed about cosmetics, then you can enhance your exhaust note by replacing the centre pipe (exhaust section between the main cats and the rear muffler). A straight-through version - without the factory resonator - makes the exhaust note a bit louder. Same (nice) tone, just louder. Will be a pretty cheap upgrade; a good exhaust shop might charge a couple hundred to fabricate such a pipe. You can of course buy namebrand pipes from overseas, like Ragazzon, Supersprint, CSC, etc. These typically increase both loudness and the bass note. Unicorse is a premium Japanese brand; their type-II rear muffler creates a fantastic Ferrari-like high pitch mechanical wail; sound awesome (mate has one on his GTA). But about a 3 month custom-build delivery time, and about A$3000 alone (just the rear muffler)!
For new tail pipes and louder sound, go with a new rear muffler. I have a HiTech Mille Miglia, from Sydney, which was around $1100. Otherwise, Ragazzon, CSC, Supersprint, etc; can be more expensive by the time you import from overseas. I have some drone, particularly under load/acceleration through the 3000 rpm zone. But at steady cruising speeds, not an issue.
http://www.millemiglia.com.au/ (speak with Lambros)
Overseas purchases can be from alfisti.net in Germany. Great to deal with.
http://shop.alfisti.net/Tuning-Styling/Alfa-GT/Sport-Exhausts:::1_17_79.html (NB: prices for use a VAT-exempt)
Alternatively, Wal at Euro Exhausts, Sydney, is great to deal with and can supply Ragazzon, Supersprint, Arqray.
http://www.euroexhausts.com.au/
:)
Thanks for your incredibly thorough response. It is immensely helpful. I was looking at maybe the Remus exhaust - just the muffler and tips - apparently these give a nice subtle note. It's around the $1300 mark so I will definitely explore the alternatives you mention. In terms of the induction - apart from loving yours! - I was also thinking about the Autodelta carbon one you mentioned. Thanks for the tip about the rough finish though.
Thanks again for the insight. Can't wait for delivery.