functional hood scoop

EDIT 3/11/16: This thread is 7 years old. tacomaworld.com was just a baby, people were Tacoma stupid back then. if you are using information from this thread to guide you Tacoma choices, you should not be working on your own vehicle. there are many more, newer threads with far better information.
Thread summary. get a snorkel or leave the intake stock.
"functional" hood scoop doesn't do anything positive or negative. spend your money, time and effort on other things.

been wanting to do it for a while, and finally made the leap. about $30 and a couple hours of thinking later, i made the hood scoop and essentially created a "ram-air".

all it takes is a retractable hose and adapter (made by "spectre") that can be picked up at autozone (they are the blue parts in the pictures). it's made specifically for custom air intakes with weird bends. togeather they go for about $25. the other $5 was for a 4'' to 3'' adapter and some hose clamps from home depot.

a little bit of cutting and trimming later, and you have fully functional hood scoop.

it might lool a little funny in the pictures, but when you close the hood, the hose retracts to the nessicary length, and fits in the engine compartment perfectly

as for performance, right away i noticed better throttle response and acceleration...nothing huge, but enough that i could tell. i also noticed slightly better acceleration on the highway too when i was speeding up to pass cars. could be due to the fact that air in now being fed in at 70mph, or whatever speed you may be going.

i haven't driven enough yet to see if there are any mpg improvements.

and if it makes any difference, i am running the K&N drop-in filter.

 

I know that some around are going to argue that making the head scoop with the scoop on the hood is actually counter productive. The airflow over the top of the hood is actually at lower pressure therefore you could get somewhat of a vacuum. Air flows from high to low pressure just like water. The best place to put a ram air would be at the front of of the grill or somewhere else the air flow isn't accelerated around the vehicle. Awesome work though!

**Note** I dont know if anyone has actually done any testing on this. If I find the time this semester it would be interesting to model the hood and run some CFD testing just to confirm these ideas.

 

i'm a mechanical engineering student, so i have access to all of the softwear and wind tunnels you need to do the testing...i may also have a hard time finding time, but i'll see if i can do anything. i just figured that even with a slight vacume, when you are moving at a decent speed, you will be getting better air flow than from inside the fenderwell.
if not, then for any offroaders, you now have a little more watter clearance...i always got worried when i was going therough deep water that i was going to go to deep since i couldn't see where the intake was. and actually, a few weeks ago i got extreemely muddy, and had to clean my filter because it took in so much mud...but my hood and the hoodscoopp area was very clean, so it would have saved me a lot of trouble there.

 

Hey same here, where do you go to school?

 

florida tech

it's in melbourne, right on the coast, about an hour east of orlando. how about you?

 

Texas Tech

 

Interesting. Should there be any concern for water (like say going through a car wash and/or washing it yourself at home)?

 

How much higher would the scoop have to be to get into the airstream? I know there's a point where the airflow over the front in will catch the scoop, both from testing that I know of and based on all the Subarus out there with scoops. Not sure how different it is with the tall vertical face of the truck though.

 

Where does the hose go when you close the hood? can it get caught in the fan?

 

i made sure to ad the propper drainage features (drainage holes at the lowest point, a sponge type system like some sports car intakes use, etc) other than the vaporized water that even the stock location would take in, water drains easily. i ran water from a low presure hose down it, and when i took out the filter to check it, it was bone dry. as for the higher pressure water you may use when washing it (like a garden hose with a nozzle, or a pressure washer) undo one hoseclamp, and it is no longer attached to your engine.

it's a semi-rigid hose, so wherever bend the hose, it stays there. every time i've opened my hood, it's in the exact same spot i left it. as for the fan, the hose is to large(diameter)/not long enough to ever get to the fan or and hot parts that could melt it.

 

That's cool you took water drainage into consideration when doing it. Just trying to cover all bases. Let us know how this works out for you over the long term.

 

So after all the work you put into it... Do you notice any differences in performance? Cooler intake temps? MPGs? etc...

 

it's hard to tell on the computer model of the truck, but as for the car, my interpretation of the picture is, and correct me if i'm wrong (i will not take offence), there is a lower pressure area right behind the grill, as well as by the windshield wipers...but that there is a "reattachment point" right where it needs to be for air to enter the scoop. granted the points or turbulence and free flow are completely different for each vehicle.

 

throttle response seems to be a little bit quicker, and acceleration is better either from a stop, or at highway speeds...it seems unchanged when you are already going between 20-50mph...maybe that is the sped at which the turbulent air pocket is at the hood scoop.

if the temperature has changed, it's not enough to tell from looking at the stocg gauge...and for mpg, i haven't used a whole tank since install, so i don't know yet.

 

Chris are you talking about for the OR hood or the Sport hood? Because the scoop (after looking at the pictures) kinda gets some of that reattachment air going over the hood.

Im just asking

 

i'm thinking about testing it the old school way...i'm going to tape pieces of ribbon in a grid across my whole hood, then drive at various speed. the ribbons will work like tell tales on a sail (for any sailors out there). i will then be able to see where air is freeflowing, and where there are dead spots or even vacumes...and don't worry, i'll do my best to try to get some pics. i'm pretty busy with school work, but hopefully i can get to it within the week.