feynman wrote:A month ago I was asking about punching exhaust holes in the floor (back when no-one could find them anywhere else) ... the thinking was that as far as the rules go, the floor is regarded bodywork, and the exceptions for closed surfaces allow two (and only two) exhaust exits.
But as we saw with the gills and slits from last year (back when exhausts were where exhaust always used to be), there is a lot of scope for topological tricks and stunts to make "two" exits into multiple exits.
FIA wrote:5.6: Engine exhaust systems may incorporate no more than two exits.
3.8.5: Single apertures either side of the car centre line for the purpose of exhaust exits. These apertures may have a combined area of no more than 50,000mm2
when projected onto the surface itself. No point on an aperture may be more than 350mm from any other point on the aperture.
So that's your limit, 350mm max point to point, and 50,000 mm2 of exhaust outlet.
Mercedes especially had nice exhaust exits with a slit just a mm or two into the shoulder of the exit linking to gills and extra bodywork cooling holes, but having trouble finding an image, so the slightly deeper slitted Ferrari will have to do (you can still just about see the slit doesn't actually reach the exhaust pipe):
... if you employed the same thinking you could easily have numerous distinct underfloor exhaust holes, as many as you want, chaining the individual exit shoulders together with slits etched into the floor/bodywork.
The nice thing, the slits would not have to breach individual exhaust outlets, nor would it need to breach the floor, the slit just being there is enough to break the reference surface and start to be counted as part of a single larger hole
... so from the top your octopus could have lots of exit ports splaying out (within a 350mm circle per exhaust), but when viewed from below, topologically and geometrically speaking, the whole arrangement still only counts as two exits.
Thermal insulation (e.g. felts, gold tape, heat shields).
