Does your post now read

I think my neighbor HAD one of those units :)

http://www.240sx.org/links/installs/hood/hood.htm

another diy hood mod write up

That one is aweful though... all that bondo when he coulda just taken it somewhere to have metal welded in.

Errr we looking at the same picture? I see very little bondo.

I would weld it so it doesnt crack after the winter.

FM tried to weld theirs, and gave up because the hood buckled.

Almost all of the drop in vents I've seen are riveted.

do they have pictures of that?

http://www.flyinmiata.com/projects/CF_hood.asp
relevant pic near bottom

You'd think that somebody would just make a drop-in fiberglass extractor that wasn't so... evo... fNf... rice... looking. I assume the rise on the leading edge is what creates the low pressure so the underhood air is pulled out. I like the subtle extractors like on the mustang below.
http://www.cervinis.com/Files/Image/..._(450x300).jpg

Yeah they used too much heat. People tig aluminum sheet metal all the time.

But riveting is gonna be a lot easier.

Has anyone thought about installing a naca duct but one that will vent out instead of in?. I'm not really sure if there would be enough flow under the hood but it seems like if it works one way it'd work another. Plus if you have one on each side i'd think they'd vent well enough while not moving to still work without speed. Plus I'd think it wouldn't look too bad, if you really wanted to could mold them in, or just leave them as is.

I actually want to try the whole reverse naca duct thing on a custom made under tray. instead of having it very open in the back have it sealed and have 4 well placed ducts to pull out air and direct it.

Preferably I'd like to vent out the fenders, it seems like it'd be the cleanest in both appearance and in terms of airflow disturbance.

I mean I suppose if you were a lotus engineer you could manage to vent out the hood and achieve some front end downforce, but otherwise i'd just say it will disrupt the airflow over the hood.

I know there has been much talk of the secondary vents, above turbo and/or IM. The ebay vents are such a good price... and so easy to get.... I really wonder if they would melt or not.

I have a few thoughts on how to test it.... how about some people toss ideas out though. I'm to tired right now to write mine out :p

These vents btw...
http://www.imagestation.com/picture/...a/e841a0e9.jpg

Ok... fiberglass and bondo.

The hoods can be welded... just have to be done slowly. As with any thing metal.. or it will warp.

no splitime, i wasnt talking about the material, I didnt think it was that much bondo, Im wondering im missing something.

Sweet a miata with a Honda badge...oi. Any thoughts on the reverse Naca?

you're not really runnin' those mirrors are you?
I'd think the only way to test them is to install and drive them in the environment. I think it'd be hard to replicate that (track and/or summer heat in traffic, etc) environment w/o gather all the data. Then consider you have to know how these things actually function (more data) to determine what effect the heat under and the air above is going to do. I say cut a hole - odds are it won't be any bigger than the next hole you cut IF these don't work.

I got my Z turbo hood vent yesterday - it is HUGE. :eek:

Eh? I went from doors with power, wanted to go to manual. I replaced my doors because the originals were very very beat. The replacement doors had been modded at the side mirrors... so I decided to just go custom.

They work decently, not the best... but I plan on installing a wink mirror in the car. So that'll offset any lack of mirror visability.

Just surprised to see them on this car... it's so purpose oriented, and then there's those mirrors. ;)

Skip the wink and go with the convex rear view, and maybe a 3" convex circle on the driver side near the vent window on the inside - you will have ZERO blind spots, and ZERO drag from mirrors.
http://www.racerpartswholesale.com/mirror.htm
http://www.racerpartswholesale.com/images/22530.jpg

The butchered up autox hood (Ben vent and large hole over turbo) works exceptionally well. Water temps have been surprisingly low.

Just ordered this for the more stealthy street hood:
http://www.genright.com/ProductInfo....uctid=LVR-1002

They are very close to size of the holes that are in the test hood. Won't flow as much as an unrestricted opening but will keep trash, prying eyes and small animals out of the engine bay. Good enough for street use.

They have other sizes:
http://www.genright.com/Search.aspx?Keyword=louver

I had gotten them to be used in place of the power windows (was easier and cheaper than people wanted for manual miata mirrors oh and lighter), but that area was so messed with that I said screw it and tossed them in the fenders.

They weigh nothing btw... aluminum housing and body... so light.
Plus I have to drive on the street, and I can't imagine the police liking a lack of 'real' mirrors.

Drove 50 miles, high speed interstate today. Ambient was ~110F on the highway and 103F at my house. Coolant temp held 207-211F at any speed from 50-85 mph. Several "mild" boosted 4th and 5th pulls, never anything to redline (construction zones, too many troopers).

This is with the extraction hood, turnsignals installed, no undertray, no radiator plate (whoops! forgot to put it on), a/c running, hardtop on, original radiator w 13psi cap, 95-5 mix.

Trip home got me caught in rush hour stop n go. Laptop battery died, so could not datalog. But the coolant temp gauge held fast at 11:45 right where it's supposed to be.