q on hood vent....

:
Mazdaspeed3
alright so i came up with this little idea and anybody who knows body work....please help me out here. subaru and their STI's have that huuuuuge freakin scoop in the middle of their hood. they make a hood scoop delete which is just an exact fit for that scoop, except its a mesh grill. i was thinking that since they have no real other means for air flow besides that scoop/vent, if (question 1) it would work the same way with our car. what i mean by that is if i can get rid of that 20lbs of ducting under the hood and just leave a hood vent above the intercooler for its primary means of air flow. also (question 2) if the hood scoop delete would just be (and i know its not going to be as easy as its said) a cut out "about the size" of the vent....and an install. so i guess the census of this huge paragraph is, will it be effective, and will it be almost as easy as a cut and place? i attached the pic and a quick mock up of what it would look like for any comments. (oh and i figured that it would help with heat soak also because well, theres a huge vent in the top of the hood. lol.)
 

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I dont think that it looks half bad, i dont own a 3speed but i do own a 3 hatch and i think that it really doesnt look that bad.As far as it being effective or not i cant honestly anwser that but i would think that it would help with heat soak like you said yourself creative idea though...
 
Im thinking the ducting is going to work better than the idea of a vent.

When we dyno our cars, with the hood closed, it makes more power than with the hood open, so being rushed through the ducting is more beneficial than just having air rushing over and into the intercooler.

I don't really care for the looks all that much either.

Creative though.
 
When we dyno our cars, with the hood closed, it makes more power than with the hood open, so being rushed through the ducting is more beneficial than just having air rushing over and into the intercooler.

i could even leave the forced ducting and slice a hole in it for heat escape out of the vent. just brainstorming for the future.
 
The problem is you need a pressure differential at the opening for any air to flow at all. It is a complex aerodynamic problem to figure it out; you may not get any air flow at all, or possibly hot air from the engine compartment actually heating up the "cooler".
 
can't do just the vent. if you wanted the WRX style scoop, that would work, provided you got a good seal on it and stuff.

I personally hate hood scoops. I like the idea that Mazda came up with a sleeper design that is still very efficient, basically using a Ram Air setup to feed the intercooler.

Neither a hood scoop or the stock mazda design is very conducive for idling or stop and go, but you're not beating on it then anyways.

That's the only benefit a front or even side mounted intercooler will have, is that in slow air movement areas, the cooler itself is more exposed to the atmosphere through the front bumper, allowing more heat transfer to take place, by letting it sort of eminate off the core. Whereas in a top mounted design, when air isn't being pushed into the intercooler, all the engine heat is rising up through it. But tis a small price to pay, since i already stated that if you're not moving very fast, then you're theoretically not going to be making any boost (unless you're on a dyno or riding a 2 step hehe), and there's not going to be any unecessary strains on the engine.

I bet on a hot day here in Florida, if you were to punch it right after leaving a stop and go area on the interstate where you've been idling and caterpillaring for 30 min, you could feel some loss in power on that first pull from all the heatsoaking going on.
 
dont think that vent will work too great. rain and other s*** can get in you intercooler...air duct or scoop are the best bet..working together with the vents coming from the grill.
 
thanks for the feedback. i really wanted to know how air would enter it if there was a hood scoop delete on a subaru. i never understood how it would cool the intercooler if there was no real access point for it to enter. but i figured since they made one it couldnt just be...well...there. i mean, i guess it could be but basically why? besides the only other motivation for making anything....money. anyway, i thought the idea was there, but i guess im s*** outta luck unless i get what was suggested and thats a scoop. not doing it. to many cosmetics and way to much fabrication. ah well.
 
from a body work stand point that would be a looot of work and really unsafe you would comprise the crush characteristics of the hood and could cause it to go through the glass when hit and it wouldnt be as easy and cuttin and stickin it in the hook would oil can and the bracing under it all in all it would be a hell of a lot of work to make it safe
 
I think that Subaru part is for if you have a fmic to also have a streamlined hood. If you have driven a STI you would be amazed how much you see the hood scoop (and spoiler) dance at speeds.
 
WHAT A DEE DEEDEE! I would love to see the ram air on the hood of our cars, rather than that all that space just for a grill ram air that really doesn't work any better than the SMIC on the MSP.
 
I think that would do the opposite of what your trying to do. As the air rushes over the top at high speed it actually creates a slight vacuum effect at the surface (Bernoulli effect - faster air = lower pressure). So with the air being at a slightly higher pressure under the hood than over the hood, the air will go out of the vent not into it. So hot air from your engine bay will be sucked out, flowing over past your IC and actually warming it not cooling it.

I don't think it would be very functional. Thats why you need the scoop to direct the high speed, cold air over the IC.
 
I think that Subaru part is for if you have a fmic to also have a streamlined hood. If you have driven a STI you would be amazed how much you see the hood scoop (and spoiler) dance at speeds.

yea that makes tons of sense. thats what i was thinking originally. theres not really any way anything could enter it. the coling would need to be from somewhere else. thus the other assumption the hot air would rise out like if we had hood vents to let out heat while out ram air let in cool air.
 
check this out!

alright so i came up with this little idea and anybody who knows body work....please help me out here. subaru and their STI's have that huuuuuge freakin scoop in the middle of their hood. they make a hood scoop delete which is just an exact fit for that scoop, except its a mesh grill. i was thinking that since they have no real other means for air flow besides that scoop/vent, if (question 1) it would work the same way with our car. what i mean by that is if i can get rid of that 20lbs of ducting under the hood and just leave a hood vent above the intercooler for its primary means of air flow. also (question 2) if the hood scoop delete would just be (and i know its not going to be as easy as its said) a cut out "about the size" of the vent....and an install. so i guess the census of this huge paragraph is, will it be effective, and will it be almost as easy as a cut and place? i attached the pic and a quick mock up of what it would look like for any comments. (oh and i figured that it would help with heat soak also because well, theres a huge vent in the top of the hood. lol.)
Real functional naca duct...starts at low pressure area of the hood masive cool air
 

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my opinion, that first vent makes me wanna throw a couple of burgers and hot dogs on it which under the right circumstances would not be such a bad idea.
 
my opinion, that first vent makes me wanna throw a couple of burgers and hot dogs on it which under the right circumstances would not be such a bad idea.

Haha legendary. Especially if you have the stock top mount. Charcoal BBQ anyone?
 
Real functional naca duct...starts at low pressure area of the hood masive cool air

ive never seen that hood before. doesnt look half bad but its basically the same thing as our stock set up....just...on top of the hood. i guess the only way to lose any of the problems with a TMIC is to get a bigger one or go FMIC. bah.


(now i want a burger)
 
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