Nice DDDenny ! Ever do the innies 180* the other way ? It seems logical that a true negative pressure would be created that way and allow the heat out rather than cool air being stopped by convection.
I haven't, but Chrysler did. They came to be known as the dog dish hoods of the early to mid 70's and were quite prevalent on trucks. One nasty little drawback was that they held rainwater and were a potential area for rusting over time. Proper drainage worked into your design would alleviate the problem.
NACA ducts ? Might even have been used pre-64 on race cars. https://en.wikipedia.org/wiki/Aston_Martin_DP215
You mean like this, backward, but not upside-down ? The coral colored part is actually the center of the hood of another Stude, turned around backward and welded on. Mike
Here's dimensions for a functional submerged inlet developed by NACA, often known as NACA duct. Beware of the ones available to buy, most of them have completely wrong dimensions to work properly - you're almost always better off building yourself. Note that the placement of such a inlet has a huge impact on functionality, the air flow and pressure around it is important - unless you're happy with just the looks, and don't mind things as air blowing out from the inlet...
How about this look? On my 61 Dodge, extended the sheet metal out to make a false scoop, done in the 70's, by an old time customizer. Sorry for the poor picture, it's a small crop out of a magazine article.
Find a picture of a '50 Merc custom. The trend at the time was a small scoop in each side of the hood about half way back where it curved down to the fender. At the same time it was customary to round off the front corners of the hood.
That's ok for a show vehicle, but if it's going to be a driver, it will dump snow and rainwater right on top of your SBC distributor. Gonna need a lot of forward rake to prevent that.
I'm not a fan of it either. Just looked up what another was looking for that fit the parameter of this site.
Like this? They were popular with the LSR crowd for a while. I used them for brake cooling scoops on a pretty fast OT pickup at onetime. They were originally aerospace bits, used to some extent in the second war. You can find them on old Shelby cars.
If someone is interested in the development of the NACA duct this is a link to a previously confidential do***ent from 1945 about it. Lets you know how it works, not just what design of the tested ones worked best. http://naca.central.cranfield.ac.uk/reports/1945/naca-acr-5i20.pdf
The concerns you need to address are 1) warpage- an issue any time you start cutting and welding on a large relatively flat area like a hood or a roof. 2) cracking- even if you get them flat, those large areas flex with the wind on the road and will work harden over time, so welds need to be top notch. 3) clearance- top of the air cleaner, dizzy, power brake boosters and anything that come close to under the hood are suspect, but the immediate problem will be working it into the under-hood bracing itself. 4) drainage- keeping the rain off the motor, and eliminating puddling on the sheet metal. 5) style- doing it in a manner that actually complements the look of your car instead of looking goofy. That might be something to run by the photo-shop gurus in the photo-shop thread. It would be worthwhile to have a better idea of the final result before you start hacking up sheet metal. I've seen what you are proposing done to mid 60's-70's Chevy truck hoods and mid 60's Comets, but I can't come up with any pics at the moment.
Yepp Back in the day we put a 58 Ford hood section in a roundy round modified roof inverted just cause we had it and thought it would look cool and different.
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