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lookforjoe

Shelby Gt500 Hood Scoop Ar3Z-16C630-Aa Template

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I hate to burst your bubble man, but you're incorrect. The placement is prime, over the turbo. The air will come in through the grille, fenders, under the car and will escape through this vent.

I can see why you'd think that. If the vent was turned around 180 degrees and the vent was on the uphill facing wind flow, then yes there might be some concern. But since the venting is angled toward the rear of the car, there is about zero possibility of inlet flow, and its all dissipation from the engine bay.

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What happens when you put your car on Vent? Does that heat enter the car?

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http://homepage.ntlworld.com/hoglabs/docs/calibra_aerodynamincs/fig06.gif

Actually, S_Moneh is right. The highest pressure is just below the windshield, also the same place as the lowest velocity of air flow. Therefore, air won't be exiting the scoop, but rather entering it, albeit slowly since velocity is so slow at that point.

Even if there was a substantial amount of airflow in either direction out of the scoop, why would it be beneficial? That is the worst area in the bay to venting hot air from, you want to keep the manifold and turbo as hot as possible.

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What happens when you put your car on Vent? Does that heat enter the car?

no it won't. that is y that the fan area is right at the top of the hood/bottom of the windsheild which has a rubber seal to seal it from the engine compartment. once you hit vent it grabs the air being pulled in at the top of the hood and gets pulled inside the car. if your seals still good no heat or engine gases should enter.

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I hate to burst your bubble man, but you're incorrect. The placement is prime, over the turbo. The air will come in through the grille, fenders, under the car and will escape through this vent.

I can see why you'd think that. If the vent was turned around 180 degrees and the vent was on the uphill facing wind flow, then yes there might be some concern. But since the venting is angled toward the rear of the car, there is about zero possibility of inlet flow, and its all dissipation from the engine bay.

Visually it makes sense right? one would definitely think so. Heck even i thought it made sense but there are graphs and studies that have been done on this effect and its not true. it the exact same thing as adding a spacer to the rear of the hood to raise the back of the hood an inch or so. it doesn't work and in deed u actually force the air back in and you in the end don't release a thing. if this mod is done right like the examples i put up above it would work

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You know what, I change my mind and you are right. I didn't think about the differential in pressure throughout the engine bay, but that makes sense. I only considered the actual flow of the fluid. The only reason I still may think what I said still has some truth is because the differential in pressure throughout the engine bay may be minimal when compared to the pressure seen from the airflow.

*busts out engineering pad*

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Trust me i looked and said to myself shoot thats a great mod. and i too wanted to do it because it does look good. but a buddy of mine explained it to me and i looked into it. it doesn't make sense to put it up that high. if it would have worked engineers would have deisgned the scoop to be back there but they didn't its placed closer to the front. sorry hussein :(

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I think it really depends on what car, and how the aero functions in combination.

When you look at these pictures, generally, the higher pressure is red, and lower is cooler, ie, green then blue to lowest pressure.

080409_19.jpg

533570d1304532455-diffusers-and-aero-in-

gti_current_002_w_hancha.jpg?w=600&h=338

clip_image004.jpg

I'm working on getting CFD (Computational Fluid Dynamics), software, in which case I can model the car, and test different aero layouts, and actually show the aero effects on our wagons/sedans.

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I'm modeling an S70 and V70 as we speak on SolidWorks and was planning on running CFD after it was completed. Stay tuned.

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http://homepage.ntlworld.com/hoglabs/docs/calibra_aerodynamincs/fig06.gif

Actually, S_Moneh is right. The highest pressure is just below the windshield, also the same place as the lowest velocity of air flow. Therefore, air won't be exiting the scoop, but rather entering it, albeit slowly since velocity is so slow at that point.

Even if there was a substantial amount of airflow in either direction out of the scoop, why would it be beneficial? That is the worst area in the bay to venting hot air from, you want to keep the manifold and turbo as hot as possible.

We'll see. I'll tape some strips to the hood, at the vent & we'll see which way they go.

I can tell you heat is escaping from the vent when idling, which is perfect to prevent the heat soak I want to avoid.

I don't want to keep the manifold & hotside as hot as possible, it gets quite hot enough all by itself without extra help, thank you very much :arob:

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you want to keep the manifold and turbo as hot as possible.

Why is this so? That Evo X pic has a vent above the turbo. Unless it serves a different purpose?

I was so ready to play around with this mod since I have a spare hood lying around, but it looks like I have to hold back for now and understand the engineering first.

Thanks for this excellent thread, and the healthy exchange. I'm really learning a lot.

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Why is this so? That Evo X pic has a vent above the turbo. Unless it serves a different purpose?

I was so ready to play around with this mod since I have a spare hood lying around, but it looks like I have to hold back for now and understand the engineering first.

Thanks for this excellent thread, and the healthy exchange. I'm really learning a lot.

I believe that's a vent as an inlet to the top mount intercooler. Their engines are mounted 90 degrees rotation from outs.

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I believe that's a vent as an inlet to the top mount intercooler. Their engines are mounted 90 degrees rotation from outs.

That is actually a forced airflow on top of the turbo. there is no intercooler there. that vent opening actually forces air straight down on top of the turbo to cool it down. its designed and oriented to point right at the turbo. those engines are mounted exactly the same as ours and turbo is in the same location

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We'll see. I'll tape some strips to the hood, at the vent & we'll see which way they go.

I can tell you heat is escaping from the vent when idling, which is perfect to prevent the heat soak I want to avoid.

I don't want to keep the manifold & hotside as hot as possible, it gets quite hot enough all by itself without extra help, thank you very much :arob:

Seriously? Why do you think there are turbo heat shields or why do people wrap their manifolds? Its to keep as much heat in as possible. The hotter the gas the more energy imparted to the turbine - hotter gas is less dense, therefore more efficient at spooling the turbo. If you do remove heat from that area, what benefits are there?

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