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Discussion Starter #1
I know this has been brought up a few times, but I was looking under my hood today while I was changing the oil and playing with the idea.

I won't get into the specifics of how I'm gonna do it in this thread, but I was wondering if any gurus out there might clue me in on the benefits of a functional hood scoop. Such as how it effects fuel economy, power, and whatnot.

I think my idea for the implementation is pretty solid, I'll get into details when (if) I find out the results would be worth the effort.
 

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Shot me 3 deer!!!
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A functional ram air hood is never a bad thing unless water gets in there. It prevents heatsoak, no matter how small. the cooler the engine, the more efficient it will be!!
 

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Discussion Starter #3
My confusion comes in on the fuel economy issue.

I would imagine it would take considerable speeds with a ram air intake to get the intake manifold out of vacuum, (if it's even possible.) But I've heard that more air = more fuel, so worse economy.
 

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Talk to Soconfused about this. He built an isolation box with a feed through the front bumper for his Steeda SRI and I beleive he had to go in excess of 70 MPH in a straight line to obtain 1 PSI or pressure inside the box. Who knows if that transferred into the motor.
 

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A ram air scoop will provide ambient temp air, and while not "forcing" air into the engine, it certainly allows greater efficiency for the intake allowing for an increase in power. I can't say if the aero drag caused by a scoop offsets the power gain in efficiency, although I'd doubt it.
 

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If you want cooling, especially at a stop, just take out the rear hood weatherstripping. Lets tons of heat out. Never had any problems with heatsoak this summer with my SRI with the weatherstripping out.
 

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^^^^
Do you have any pics of how you removed it?
I've heard of people doing this, but never seen a how-to, or even pics of it.
 

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Discussion Starter #9
Well, that's the thing Jetrinka, it would be partially for cooling, but partially because I love the look of a hood scoop.

However, I won't just tack a non-functional one on that'll only add weight and drag.
 

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The weather stipping on my focus was in 2 pieces. It has a female side the lenght of the strip and it just fits over the male lip of the front cowl. Just pull off one side of the strip, then pull it off all along the cowl. Works great for releasing underhood heat.

As for the hood scoop you would either have to mount the scoop over you intake or mount it somewhere else and route it to the intake. The new RaceCraft(Saleen) focus that is coming out has a scoop that site over the right side of the hood in the middle. Unless you are going to seal everything up then your not going to get a ram air affect. You will allow cooler temps to the intake and cooler air into the engine = more power.
 

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Discussion Starter #11
I'm thinking of mounting some air ducts to my front stress bar, which will seal up with the hole in the hood when it's shut. The ducting will lead to the isolation box for my SRI.
 

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coffee, have some
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The weather stripping just peels right off, easy to do. A knife might help too. You'll notice a little more fog on your window though.

Also, have you looked into NACA style ducts? They not only look awesome, but they also limit drag because of the design. Designed by NACA before they became NASA. How cool to have a space shuttle design on your car!

I'm drawing out plans now for an intake-box that will draw incoming air from the NACA duct to the intake and at the same time, help block off engine heat to the intake. A lot of work for just a SRI right? but it's fun.

Check these links out for some nice ducts and info:
Ducts:
http://secure.mckinneycorp.com/AMAZING/itemdesc.asp?ic=M-4410&eq=&Tp=
How-to's:
http://www.revlimiter.net/mods/duct.html
http://www.sportcompactcarweb.com/projectcars/0706_sccp_acura_rsx_s_turbo/index.html
And info:
http://en.wikipedia.org/wiki/NACA_duct

There, now you don't have to go searching yourself [:)]
 

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Discussion Starter #13
Jet, looked through Socon's thread on the matter. The pressure his ram air made actually blew seals in his box!? That's more than I would have hoped for, and good news for hoping there is efficiency to be had from this.

I don't really want this out-there idea to make gobs of power. I'll leave that responsibilities to tried-and-true methods. It'd just be cool if I got some improved highway MPG or passing power out of this. I'm kindof thinking of re-thinking the intake from the throttle body boot forward, however. For my intentions, that battery is in a pretty inconvenient place... if this goes anywhere at all, the battery might be relocated.
 

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BodyKits=PantiesDrop
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i've been thinking about this same thing for a while, and Mr.B those NACA links were amazing, i'd love to do something like that if i wasn't rocking a fiberglass hood...

with my cervini's i was thinking about using sheet aluminum to basically create a box that would encase the SRI and then mount flush up against my driver's side scoop with weatherstripping to create a sort of ram-air effect...if nothing else it will at least look cool haha
 

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You dirty dawg, that's what I'm doing. You can't do it also......jk

I picked up a cool duct from Hotrodwagon and will be working on it tonight and tomorrow. Probably won't have it finished till this weekend though.
 

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I am doing a new 'winter project' based on original idea by Bluefont. Essentially, its an under the hood 'hood scoop' to remove engine bay heat. Much cheaper than trying to fit a real hood scoop I would think. Also prob work better.
 

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Discussion Starter #18
Hey SoCon! Glad to see you in the thread.

My idea thus far is to relocate the battery to a N-S orientation instead of stock, and try to run intake ducting up along the driver's side of the bay, to the back of the engine over the exhaust manifold.

I know having your intake right over your exhaust mani would invite heat soak problems, so this is probably a project for -after- I get ahold of a wrapped header to combat the issue. I'd keep the MAF tube near the throttle body boot as in my current setup, but relocate the intake filter, to sit directly under where a hood scoop would go, and make an isolation box for said filter that was fed by the scoop.

The upper strut tower brace will likely be used to mount the new box and (cylindrical, not conical) filter. With the scoop right there, and the filter right there, I hope to leave all the fluid dynamics calculations out of it, since I'm not an engineer. Probably not anything I'll be doing soon, but possibly in the future... my overall goal is a very well-breathing N/A setup with a mild shot of NOS to make me smile when I floor the throttle.
 

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Wow those are links are awesome. I never thought about a reverse scoop working. If you can get the duct behind the light and have it come in right before the battery and build a box that will seal to the hood that would probably work and work well from what I have read. Come on guys get on it!
 

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Roland07 >> Interesting!!! Here is maybe some help.
"try to run intake ducting up along the driver's side of the bay" >> The pipe volume is what matters, not the shape. So if you use a 3" pipe, you can 'squish it' down if necessary (go behind battery or over the wheel area). Its the bends that have by far the most impact on flow. If there not smooth and linear it really whollops the whole flow thing.
"I know having your intake right over your exhaust mani would invite heat soak problems" >> Only during idle. I recently ran a probe into the engine bay, over the exhaust right at the firewall. Within 30 sec the temp exceeded my meters ability to measure (158F). But! As soon as I started moving the engine bay temps dropped like a rock to ambient +5F. So some shielding, plus the fact that air is very hard to heat (or cool) in a short run like your duct should negate the effect to some degree.


Just a thought >> If your going to mount a working scoop to the hood, then you may find it easier to affix your ducting to the hood itself. That way you don't have to move anything. Instead of a round filter use a flat filter either at the scoop, or taking a tip from the 08 airbox, you could use it (make you own) and make a coupler to slide down and align when you close the hood. You have ~ 2" clearance between the hood and the engine. Little less as you get more towards the front (~ 1.5"). There is this foam you can get (Name escapes me) that is crushable and will hold its last shape. You can use that to get very precise clearance measurements.

Oh and of course. Measure 3 times before you cut. And be aware its VERY difficult to get a 'straight' measure under the hood (as very little is straight.. take my word for that!). Take the time to make cardstock fullsize models for test fit. It will crush easily and leave other telltails of where your not quite right before you commit.

I will be watching for this. I sorta got a pic in mind but will be awesome to actually see it.
 
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