Wu-Watt

iTrader: (24)

So I'm considering installing these NACA ducts in my hood.


In this area.


Then shim the hood a little bit maybe 1/4".
Then remove this plastic under the hood.


This should allow air to flow in and out. Might even cool the engine? What cha thinks?
*** buying a CF hood.

mr. sparco

iTrader: (13)

https://my350z.com/forum/autocross-r...tock-hood.html

Chebosto did something similar back in 07. Lots of Jeep/off road guys do this by installing hood vents off other make/models.

I'm doing something and prefer the OEM hood as well.

KingBaby

iTrader: (3)

What do you want it to do? Why would you remove the plastic covers?

SR71

iTrader: (1)

Hood spacers/shims make your hood look like the **** don't fit. I don't care if it works or not, if it's on a track car fine but for the street it just makes a car look busted.

mr. sparco

iTrader: (13)

Body work/fitment/paint has to be perfect to pull it off.

Wu-Watt

iTrader: (24)

The shims and removing the plastic is just to make some room for the air to flow thru.
I agree if a hood is shimmed too much it looks dumb. I plan on using a couple thick washers.

bealljk

iTrader: (13)

This is solely my opinion but you can open your hood up and allow air in but air will not flow through your engine bay unless you give it a place to go…

if you do this mod consider where you want the air to flow and do your best to clear a route…

I personally think it looks tacky but that just my opinion...

terrasmak

iTrader: (8)

Exactly. Normally you open up that area to allow air to flow out so your eng bay is cooler.

JCITY

iTrader: (2)

What exact location will you place the ducts?
What size are the ducts?Too small will look out of proportion.
Are you doing this soley for performance or,looks?
I agree that the OEM hood is pretty boring.I did Aston type vents
on my car.They are made out of finned aluminum billet.I slotted
the valleys.They do look good.However,the amount of air from
the ducting I did to the engine is probably not worth the effort.
I did mine mostly for design purposes.

Wu-Watt

iTrader: (24)

The point of this is not for looks, and I know its borderline tacky thats why I want to discuss it before I do anything.

I want the air to flow in the vents, over top the engine bay (generally), and out the back of the hood which I've raised a bit with a few washers.
Removing the plastic and rubber trim will make room for the air to flow out.
I figure the air has a way in and out, in the same direction.

Size


Here's my car, it's clean. Function might cost a little bit.
A unpainted CF hood would prob look worse.

bealljk

iTrader: (13)

I'm not throwing stones at ya, don't take any offense to what I say, in fact, take it with a grain of salt.

It my opinion that you're airflow gains may be achievable, but the cost and trouble you'll go through to get 60 cfm of airflow at 75mph will be a big pain in the ***, disproportional cost, and will ultimately take 'value' away from the car.

and I believe that if car needed more airflow to vent engine temps than nissan would have designed the car with some sort of hood vents.

Great looking Z btw…and if you choose to do this and it completely looks like *** you can find another red hood and be back at square one...

Wu-Watt

iTrader: (24)

Ya it's cool man, just a discussion. I figure it will cost $200. Car is paid for, I'll be buried in it. Lol
The 350z wasnt designed to be as sporty as it could be potentially. It has a heat problem, most people know that.
My car looks stock, but it has almost all the n/a mods it can have. Stock motor.
I added a oil cooler this year also. (Setrab)
A NACA duct doesnt draw in air like a scoop it "steals" air on the boundry layer also.
I'm looking around on google for more on this too.

Z-Crazy

These vents will help to keep the engine bay a little cooler at lowet speeds. This will work due to convection as hot air will try to rise up and possibly move out of the vents. At higher speeds, the air will need an escape route.

The paint/finish on these vents will decide the looks. If you can match it with the finish on B-pillars or match paint with the hood itself, it will look good.

Do post pics if you install it.

misterniceguy

iTrader: (14)

I think that NACA duct would look sweet. It did on my old Miata. I had one on the driver side installed on my stock hood.

But the flat area of the hood is generally low pressure and will not intake are very well. And the cowl area is generally a high pressure area that will not extract air very well.

bealljk

iTrader: (13)

True, because they knew the GTR was coming and if they wringed out the full 450whp the VQ is capable of the debut GTR would need 500+...

Cool man - well, if you do pull the trigger, make a dedicated thread - I'd love to see how it turns out…awesome that you have the car paid off, opens up alot of options. Give 'em hell!

415mm

iTrader: (103)

I had wanted to do this but with different vents like the ucas ones off zil via

mr. sparco

iTrader: (13)

Not so good on a Honda.


Not bad on the G.

Not bad on the 370.

350Zdj

iTrader: (3)

wanna see this on an HR hood

Wu-Watt

iTrader: (24)

Ya I actually found a lot of info on the Miata forums, via google. And the A/C Cobra forum.
I'm doubting air will flow in and out as easily as I thought. But if it makes an improvement then it would still be worth it to me.

I'm in the hvac trade, I have a thermometer that I can run a wire into the engine bay and take readings with. I'm going to start by getting readings back and forth from work. Then maybe remove the plastic I mentioned and shim the hood. If I get some drafting action it may draw some heat out of the engine bay.
Thats how convectional gas appliances work. The cooler outside air draws the hot vent gas up the c-vent and out the roof or chimney.
The cowl area is a high pressure area but the air is still going somewhere so it would have to take some heat with it in my opinion.

Thanks for the pics Sparco. I guess you can buy a CF hood with GTR style naca ducts. VIS sells it I think. It looks good on that red 370 for sure. His might be custom....
This is the VIS 350z GTR hood.


Seibon for the 370z.

mr. sparco

iTrader: (13)

Instead of shimming the hood you could try removing the rear weather/rubber strip to let the air escape.