@rachaeljf - let me know if you'd prefer this be moved to a separate thread...
So, I made some drawings based on
@Brayden_connolly photo's - I hope that's OK - to evaluate details
The hatching represents where he cut through the 'frame' section
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These are LARGE vents!
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So, what I'm leaning toward for the moment at least, is a vent that involves little or no welding, so no cuts through the frame, only though the single skin membrane in between
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I'm going to cut holes in the tub wall & inner fender
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3x4" fits between the weld flanges (on the inside) . This would be modded to angle the flow diagonally to the wheel opening/brakes. The brake ducts built into the nose/lower pan on my C30 are only about this size.
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Inside, 3x4 channel could be used
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I think I'm going with corrugated tubing - this is 3.75" inlet, 4x3" outlet. Easier to tweak for fitment - esp. since I usually eyeball all my measurements / placements - so has to be a forgiving margin for error there.
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The rectangular end will pass through the inner fender into the guide flange on the outside. For the frunk tub end, I can cut a 4" hole, add a circular flange to it for the tube to attach to. Easier than trying to cut the rectangular orifice in anon-flat surface. That area of the tub is a bunch of compound curves, not flat at all. Doing it this way, I don't need to mess with the AC hose/harness pass-through on the right, as it will sit inboard of that.
I'm going to cut the holes & go forward. I can always make cover/blanking plates if I don't like the way it turns out.
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