f355 subwoofer

That's always been a challenge on a 355. The only option that I was able to do was to add good amp in the trunk (I made a box and covered it with trunk carpet), change the stock speakers to better grade Alpines.

For a sub - the only thing I would suggest is to get a removable tube that you can place behind the seat. Sometimes called a bass tube. If you have a spider make sure there is room for the seat to move during the top sequence cycle.

I can tell you how much NOT to mount a sub in the rear firewall. I've seen this done. The speaker magnet will extend into the engine bay. It's the quickest way to "devalue" your car. I've done some concours judging in my time and whenever I see this I want to cry.

The other benefit of the bass tube is that if you ever want to do a car show, you can unsnap the tube and remove it in 10 seconds... car will look perfectly stock.

 

You might be able to do something similar to what Mdshore348 did here:
http://www.ferrarichat.com/forum/showthread.php?t=99153&highlight=348+stereo+install
BT

 

hi, i upgraded the stereo in my 355, it was hard to do but worth the effort, fitted an alpine amp in the front hood next to the tool kit, took the air vents off the dash and replaced the factory tweeters with infinity ones, door cards removed and infinity speakers installed, the door carpet is acoustic so in theory its not meant to affect the speaker noise(but it does), put a alpine head unit in the dash and to finish off placed 2 clarion self amplified shoe box subs behind each seat, i think it was around £150 for each sub, but they fit nicely behind the seats( its a real good sound from the new system, even with a capristo exhaust!!!

 

Also, check out this setup (also a 348) with the sub in the trunk ported through the a/c ducts!
http://www.cardomain.com/ride/5048?&page_id=5048&cat=20&val=100

BT

 

Take a look at this link
http://ferrarichat.com/forum/showthread.php?t=59500&highlight=subwoofer
I mounted my sub where the storage box was, used same mountings, and hole in carpet.
PM me if you need more info.