DaWaN

I am not sure where this thread is heading too, but I think you guys are just a bunch of spitfires. Just keep it down to facts and data.

I am in the market for some louvers and I already bought an extra bonnet so I keep my pristine original one original. I have a '99 NB btw, so I want NB louvers.
The car is mostly a street car so I would like to maintain my original bonnet hook so keeping the standard bonnet bracing is relevant to my interests.

Shane seems to be very capable to draw up some louvers and produce them. They also keep clear of the bracing. So far so good.

Now the all the discussion about pressures, engine bay temperatures, aluminium vs. iron etc. does not interest me. The bulk of the heat (I guess around 90% or even more?) of the engine is transfered to the air through the heat exchangers in the front of the car. These heat exchangers work because air flows through them. The thing these louvers should accomplish is to allow for more air flow through the heat exchangers. Air flow through the heat exchangers is all we care about.

Now of course checking pressure maps is a very good start to determine the best place for these louvres, but I am interested to see actual air flow measurements with these louvres in place, because I think these louvres have some influence on the pressures around the front/hood area. Anyone with experience in aerodynamics is free to comment on this as I am no expert!

I think everybody here should be intelligent enough to make their mind up based on facts. Do not feed the trolls. I do not care if my louvres get made by Ryan or Shane. The most important thing to me is airflow through the heat exchangers and data to back up the claims. Seeing these louvres installed on multiple vehicles with good succes is important to me. Secondary things are: looks, easy installation, (shipping) price, and being able to retain the standard bracing. Whoever does that best gets my money, be it Shane or Ryan. Just my

ThePass

iTrader: (3)

Not jumping the gun until the final pieces to the puzzle are tested.. the outer pressure maps are already pretty well documented in our community, but there were a few specific areas I wanted to look at in more detail than what has been documented before. There are some key differences between the NA and NB, it's interesting how subtle the differences in hood and body shape between the two models make some distinct differences, but also there are areas that are quite similar. I also wanted to look at under-hood pressures, and I suspected that it would be a fairly even pressure everywhere. Turns out that's not entirely the case

Most interesting was our testing of several of the existing common vent options, some worked pretty well and some didn't.

As an aside, another thing that really surprised me was the effect on the pressure differential across the radiator from clean air ahead vs. a car 50 ft. in the distance (at 65 mph). I wouldn't have expected a big change from a car leading that far away.

Oh, I've also made a few tweaks after string testing the hood's airflow as well.

This isn't the only part in the works, so I've had my hands full. I'm taking the weekend off and going on a motorcycle ride

Developments coming this week though. I'm working out the details on a part of this that I'm rather excited about, but still working out whether it is cost-effective.

-Ryan

hmongmiatanb

Yaaayyayyay. Take my money

jpreston

iTrader: (4)

Have you considered making two different versions? An m.net version that doesn't require cutting the stock bracing, and an mt.net version that does require bracing removal but is 100% optimized based on pressure data. I'm not at all interested in the proposed m.net version, but will send payment right now for a fully optimized version.

ThePass

iTrader: (3)

jpreston, standy by I believe I have figured out both. In terms of my priorities on this, performance/effectiveness trumps avoiding the bracing.

I'm just keeping in mind that a lot of guys would like to retain enough bracing that the hood doesn't become a floppy mess

-Ryan

BlackBandit

iTrader: (2)

Will we experience any hood lift at high speeds?

tomiboy

iTrader: (3)

I would think the opposite would happen...less hood lift

BlackBandit

iTrader: (2)

Well I was curious to his last post about it becoming a floppy mess. What type of bracing was he suggesting?

Leafy

iTrader: (1)

My hood with way more bracing cut out than the race version probably would goesnt have any hood lift up to 85ph. Havent taken the car faster than that. Its wicked floppy to the touch though or if you have the hood up in the wind. But there's also the aerocatches keeping good tension on it, so no idea how good it would be with the stock latch.

BlackBandit

iTrader: (2)

Would it make sense to create a bracing that would be sold with the louver? I thought of a bracing that would surround the diameter of each louver underneath for more stability. I would pay more.

Leafy

iTrader: (1)

IMO the only real problems with taking the bracing out on street cars are; loosing the stock hood latch, and loosing the little hole that the hood prop goes in. You can easily avoid the bracing for the hood latch.

BlackBandit

iTrader: (2)

Thank you for answering this. I will more likely make cuts for a street use and hope that it will be efficient enough for a track day or three in a years time.

OGRacing

iTrader: (1)

I did the De-Bone hood. removing all the hood bracing.. hood was a sloppy mess event with aero catches.

Leafy

iTrader: (1)

You definitely want to leave the bracing along the sides. But taking the stuff out of the middle isnt bad when the hood is down and secure.

Lincoln Logs

iTrader: (1)

I've had no issues at Autoclub Speedway (120+mph on the front straight) with my hood bracing cut up for the GT500 vent using Aerocatch and deleting the front latch.

ThePass

iTrader: (3)

I installed the GT500 vent in Sean's car ^

The final design of these louvers are looking like they'll require removing less underhood bracing than needed to be removed for the GT500 - the hood should be fine for keeping the stock latch as the fastening point or hood pins.

Just to clarify for those reading along, Leafy, OG, etc. who are talking about hoods that get all flippy-floppy are referring to hoods with damn near no bracing left at all - for weight savings, not to clear hood vents.

-Ryan

OGRacing

iTrader: (1)

yep i did that. anything over 25mph. it was like a flag. plus the hood is aluminum. I didn't weigh the removed material, but it wasn't very substantial at all. maybe a few pounds 3-4.

correct

jpreston

iTrader: (4)

My current hood (still without vents) has all of the stock bracing removed except for the outside perimeter and what's required for the hood latch. I'm only using the factory latch and attachment points and don't have any complaints.

Awesome. Anxiously awaiting this.

hmongmiatanb

Any chances a few batches will be pushing through earlier Ryan? Namely for the nb hood.

Mobius

iTrader: (2)

Of course I just purchased myself a spiffy CF Mini piece to ventilate my spare hood with ... now you come along with your so-called "testing" and "data" (honestly, really, WHO DOES THAT ANYMORE? It's the age of CAD and cheap China manufacturing - while I typed this post, I created and sent off my new 3d UltraMiata wing design to manufacturing, and expect the first container tomorrow via drone) to show me where I should ventilate it for best effect, which undoubtedly will not be where the Mini piece will look best.

So gitrdun, my funds are waiting.