BB air box covers

I can't answer your question but I must say, that is one hell of a picture!

 

The covers are designed to create a ram air effect from the rear deck lid vents which face the front of the car grabbing air then piped from the channels in the rear deck to the carb cover intakes, excess air exits near the rear glass from the glass intake covers you have cut outs in from the low pressure effect creating a vacuum thus increasing the ram air effect, those slots defeat that purpose it seems.

Perhaps the guy thought it would bring cool air in which was the reason for the cut outs or increase the ram air effect somehow by allowing the air to escape easier

 

I thought they all looked like that. These are from my 365
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The drawings for the original design in Nichols book show air escaping from the front and sides of the glass covers, then air being rammed in from the rear louveres to the air cleaner intakes.

Maybe the covers were just designed to let air out and cool the air cleaner covers for cooler air.

My car doesn't have the cut outs

 

I see your point, the rear wing and buttress create a low pressure area by the rear window, then that rushing air will be grabbed by the rear vents on the deck lid then piped though the fibreglass channels to the air cleaner intakes, seems like ram air to me.

As I mentioned earlier it seems the glass carb covers which are designed to vent air may be to cool the air cleaner covers

 

Mine are glass unless I am mistaken, fairly sure they are, my no. is 24445

 

that's what mine was like. mine also had the rear deck unlocked light too.

 

Just checked, learn something new about these cars all the time, mine are hand laid fibreglass as I can see the matting in them

I agree on the covers not creating ram air though the Nichols book implys that in the drawings and narration, but look at the air flow from the rear deck lid carb intake vents which are angled forward vs the cooling vents on the rear deck are faced the opposite direction towards the rear of the car, then air is channeled via a fibreglass tunnel to the rear of the air cleaner intake covers and see what you think

 

Makes sense on the heat dissipation.

But also remember the early carb cars in the 70s had small production maybe 12 Boxers a month, not much more than 150 cars a year average so anything could have happened with each small batch made each month

 

mine are glass or plastic without slots, havent seen a 512 with the 365 slots though but anything is possible. mine has 365 headers and it doesnt bother me one bit. didnt know the 365's had aluminum covers either.

 

Phil,

So if this is the case, Besides looking better when the Clamshell is lifted, What's the benefit of stripping off the Airboxes and putting those little Stainless Steel Mesh covers on the carb stacks?

Argento

 

I would say sound mostly and a slight increase in HP, something to be verified on a chassis dyno.

 

My '83 doesn't have any slots in it's covers either.

My guess is that the slots were to dissipate heat from the engine compartment.
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I just looked in my copy of Mel Nichol's Boxer book.

Here's a photo that states, "How the carburetter's air gets in and out."

The second photo shows the slots on a 365BB. None of the photos in the book of the early 512s show any slots in the covers, just the 365s.
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