Some brief mocking up and measuring shows that this'll be a real close fit to the non-m hood. I already have a little bit of interference to a formed flange supporting the hood to the stock strut bar, which is fine with aluminum, but the carbon would wear through and this could cause a failure. The M3 has more clearance here due to the different hood design, so I might need to get creative. The strut slots look a bit longer than the stock ones, which is good, because this bar needs to be removed as one piece and the studs are at an angle, not vertical, so the slots will provide appropriate clearance here.
The carbon filter housing is incredibly light, it doesn't damp knuckle noise as well as the stock pieces. I'll be paying close attention to whether or not this adds too much noise into the cabin, with the concern being particularly lifters and valve train at low loads. I can always add sound insulation to this later.
There is a little bit of an air gap (<1/4" x 6" long) at the firewall to air filter housing interface where the strut brace attaches. My current plan is to fill this with Butyl to avoid pulling hot unfiltered air into the cabin.
Here's how it all goes together, as I know many folks are curious (as was I):
Carbon piece gets bonded to become the windshield support, firewall insert fits over two square bosses on the windshield support:
Strut brace to support adapter sits directly on the bosses in the windshield support:
Filter housing goes on top of Strut brace support adapter, two square washer/bosses fit through holes in the filter housing, two fasteners go through this whole stack. None of the carbon pieces are in compression:
Getting my hood height measurement datum set:
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