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Essential cooling mods?

Akuto

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They use to make a custom one for the grp downpipes, not sure if you can buy the blanket separately without buying the downpipe
That must be what I'm thinking about then lol :crazy: thanks



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UFO CTR

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Cowl induction test at low speed (up to 70 MPH, hood seal removed):


What is cowl induction: https://itstillruns.com/pros-cowl-induction-race-hood-5571485.html
I'm not sure what I'm looking at here, as I can't tell if that is top of hood air or engine compartment hot air...any chance the same person in the video can add some sort of colored smoke dye to see if hot air is in fact "sucked" out from the top of the hood?

Sorry for being an ass, but in theory it should work as the free sea air is moving at velocity higher than the air inside the engine compartment. This velocity delta creates a high pressure zone inside and low pressure zone outside...high pressure like to move towards low pressure (similar to water want to flow down hill). so it should drawl hot air out.
 

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I'm not sure what I'm looking at here, as I can't tell if that is top of hood air or engine compartment hot air...any chance the same person in the video can add some sort of colored smoke dye to see if hot air is in fact "sucked" out from the top of the hood?

Sorry for being an ass, but in theory it should work as the free sea air is moving at velocity higher than the air inside the engine compartment. This velocity delta creates a high pressure zone inside and low pressure zone outside...high pressure like to move towards low pressure (similar to water want to flow down hill). so it should drawl hot air out.
I was looking for the paper streamer to get sucked into the hood (it didn't) but that's only at speeds up to 70 MPH. I'll test it again with a piece of softer string next, sometime down the road (but no promises of ETA). I don't track my car so the test is only conducted for my own gratification.
 

Akuto

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I'm not sure what I'm looking at here, as I can't tell if that is top of hood air or engine compartment hot air...any chance the same person in the video can add some sort of colored smoke dye to see if hot air is in fact "sucked" out from the top of the hood?

Sorry for being an ass, but in theory it should work as the free sea air is moving at velocity higher than the air inside the engine compartment. This velocity delta creates a high pressure zone inside and low pressure zone outside...high pressure like to move towards low pressure (similar to water want to flow down hill). so it should drawl hot air out.
One of the highest pressure zones on the entire car is right there where the hood and the windshield meet. Under our hoods is a lower pressure zone, so you have your zones backwards. Thus hot air moves into the hood.

It also states this information within the very first paragraph of the article that TypeSiR posted.
 

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One of the highest pressure zones on the entire car is right there where the hood and the windshield meet. Under our hoods is a lower pressure zone, so you have your zones backwards. Thus hot air moves into the hood.

It also states this information within the very first paragraph of the article that TypeSiR posted.
so is there a local blockage that's creating this high pressure zone (i.e., a perpendicular wall)? I think it should work like a toilet (for lack of examples), right?...once you hit the flush, water from the tank rushes straight down the 4" drain, and thus dragging the waste water from the bowl down with the moving flush water? it should work the same, no? fast air moving above the hood, should drag air out from top of hood?

what you're saying right now is air actually blow in from the top of the hood; is that what you're saying?

upload_2019-9-5_6-9-30.png
 

Akuto

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so is there a local blockage that's creating this high pressure zone (i.e., a perpendicular wall)? I think it should work like a toilet (for lack of examples), right?...once you hit the flush, water from the tank rushes straight down the 4" drain, and thus dragging the waste water from the bowl down with the moving flush water? it should work the same, no? fast air moving above the hood, should drag air out from top of hood?

what you're saying right now is air actually blow in from the top of the hood; is that what you're saying?

upload_2019-9-5_6-9-30.png
The windshield is the wall, and no it doesn't work like a toilet system, somewhat close on the concept though, maybe. Fast air moving above the hood does not pull out air from the top of the hood unless you have a louver which then creates the louver effect. We have no louvers and the very end of the hood on the windshield is not a louver nor opened the correct way, as it is facing the back of the car and not upwards.

Yes, I am saying air is blown inwards from the back of the hood. The faster the speed, the more air gets sucked in. For us, this is bad, as it disturbs our venting air routes underneath the hood (most air routes under the hood lead to the side vents) and causes under hood pressure, which in turn causes front end lift at high speeds (60+)
 

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The windshield is the wall, and no it doesn't work like a toilet system, somewhat close on the concept though, maybe. Fast air moving above the hood does not pull out air from the top of the hood unless you have a louver which then creates the louver effect. We have no louvers and the very end of the hood on the windshield is not a louver nor opened the correct way, as it is facing the back of the car and not upwards.

Yes, I am saying air is blown inwards from the back of the hood. The faster the speed, the more air gets sucked in. For us, this is bad, as it disturbs our venting air routes underneath the hood (most air routes under the hood lead to the side vents) and causes under hood pressure, which in turn causes front end lift at high speeds (60+)
uh, so the angle of the hood doesn't deflect the air flow away from the tip of the hood? are you sure the reason why lift is generated is NOT because of the diagram the I've posted in my previous post? the air foil is how a "wing" generate its lift is it not? the cross section of the wing don't look like cross section of a car?

what about under hood pressure from air going in the front of the car? won't that blow the hood clean off?

how bout this...not sure if you smoke or not, but when smoking (tobacco or da-kind) in the car, you crack a little window open and put the cigarette/joint near the window, does the smoke get suck out or blown back in? oh and it the window open considered a "louver"?
 

Akuto

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uh, so the angle of the hood doesn't deflect the air flow away from the tip of the hood? are you sure the reason why lift is generated is NOT because of the diagram the I've posted in my previous post? the air foil is how a "wing" generate its lift is it not? the cross section of the wing don't look like cross section of a car?

what about under hood pressure from air going in the front of the car? won't that blow the hood clean off?

how bout this...not sure if you smoke or not, but when smoking (tobacco or da-kind) in the car, you crack a little window open and put the cigarette/joint near the window, does the smoke get suck out or blown back in? oh and it the window open considered a "louver"?

The angle of the hood allows air to flow close to the hood line, if it didn't, the ram air scoop on our hood wouldn't work. so no, it doesn't deflect air away from the back of the hood. Plus the high pressure zone on the windshield pushes air in all directions around it, towards the roof, bottom of the windshield, and sides. The bottom of the windshield typically doesn't have the best route for air to travel and then becomes a high pressure zone or "turbulent".

The diagram is a wing. a wing aerodynamic diagram is entirely different to the front area of a car, though some of the concepts (very few) are used in the front. Lift is generated period. But not like the way the wing generates it. It is generated from trapped turbulent air underneath the hood that comes in from the grills. Honda designed a way to get rid of the turbulent air (but not all of it due to many factors) through the side vents, and also through the specially designed ram air scoop that has channeling under the hood that is vented to also guide turbulent air to the side vents.

The hood is designed to handle a specific amount of under hood pressure before it shoots, off, typically this is a very high factor due to safety regulations. The lock on the front, and the two points in the rear also help it to know get blown off. Also carbon fiber hoods that weigh under 10 pounds are required to have 2 extra points to be held down. We use hood pins for that very reason, and some times more than 2.

The smoke would be sucked out due to the louver effect. Louvers effect is when fast air passes over an opening thats filled with air that is not traveling as fast as the outside air. This causes a small vacuum at the opening sucking out the slower moving air. You can see this effect not just with louvers but with many many different exhaust systems, an example would be an H-pipe or an X-pipe which help draw out more exhaust from the motor. HD motorcyles have to use an H-pipe on their exhaust due to one pipe being shorter than the other. This allows for equal amounts of exhaust flow from both sides of the motor..... BUT YES, in that instance the window does act as a louver.

The main reason why the cowl of the hood does not act as a louver like the window does is because their is NO high pressure zone that is pushing the air into the window, (unless you roll it down completely then you get what is called an unstable louver effect, which is a pain in the ass to explain), the cowl of the hood, however, has the turbulent air from the windshield wanting to escape to a lower pressure zone, which at that speed, its underneath the hood.
 

Akuto

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uh, so the angle of the hood doesn't deflect the air flow away from the tip of the hood? are you sure the reason why lift is generated is NOT because of the diagram the I've posted in my previous post? the air foil is how a "wing" generate its lift is it not? the cross section of the wing don't look like cross section of a car?

what about under hood pressure from air going in the front of the car? won't that blow the hood clean off?

how bout this...not sure if you smoke or not, but when smoking (tobacco or da-kind) in the car, you crack a little window open and put the cigarette/joint near the window, does the smoke get suck out or blown back in? oh and it the window open considered a "louver"?

Also here is a video showing cowl induction. I have no idea what the guy is saying though lol regardless this is what opening that piece at the cowl does.

 

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The angle of the hood allows air to flow close to the hood line, if it didn't, the ram air scoop on our hood wouldn't work. so no, it doesn't deflect air away from the back of the hood. Plus the high pressure zone on the windshield pushes air in all directions around it, towards the roof, bottom of the windshield, and sides. The bottom of the windshield typically doesn't have the best route for air to travel and then becomes a high pressure zone or "turbulent".

The diagram is a wing. a wing aerodynamic diagram is entirely different to the front area of a car, though some of the concepts (very few) are used in the front. Lift is generated period. But not like the way the wing generates it. It is generated from trapped turbulent air underneath the hood that comes in from the grills. Honda designed a way to get rid of the turbulent air (but not all of it due to many factors) through the side vents, and also through the specially designed ram air scoop that has channeling under the hood that is vented to also guide turbulent air to the side vents.

The hood is designed to handle a specific amount of under hood pressure before it shoots, off, typically this is a very high factor due to safety regulations. The lock on the front, and the two points in the rear also help it to know get blown off. Also carbon fiber hoods that weigh under 10 pounds are required to have 2 extra points to be held down. We use hood pins for that very reason, and some times more than 2.

The smoke would be sucked out due to the louver effect. Louvers effect is when fast air passes over an opening thats filled with air that is not traveling as fast as the outside air. This causes a small vacuum at the opening sucking out the slower moving air. You can see this effect not just with louvers but with many many different exhaust systems, an example would be an H-pipe or an X-pipe which help draw out more exhaust from the motor. HD motorcyles have to use an H-pipe on their exhaust due to one pipe being shorter than the other. This allows for equal amounts of exhaust flow from both sides of the motor..... BUT YES, in that instance the window does act as a louver.

The main reason why the cowl of the hood does not act as a louver like the window does is because their is NO high pressure zone that is pushing the air into the window, (unless you roll it down completely then you get what is called an unstable louver effect, which is a pain in the ass to explain), the cowl of the hood, however, has the turbulent air from the windshield wanting to escape to a lower pressure zone, which at that speed, its underneath the hood.
"Louvers effect is when fast air passes over an opening thats filled with air that is not traveling as fast as the outside air. This causes a small vacuum at the opening sucking out the slower moving air." This is what I'm saying, and this does not occur at the trailing edge of the hood, regardless how small the suction/vacuum is?

If I grab my garden hose and shot a stream of water horizontally at my hood, you are telling me the water will not deflect upwards? Shouldn't water (similar to air) deflect perpendicular to the incoming angle?
 

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"Louvers effect is when fast air passes over an opening thats filled with air that is not traveling as fast as the outside air. This causes a small vacuum at the opening sucking out the slower moving air." This is what I'm saying, and this does not occur at the trailing edge of the hood, regardless how small the suction/vacuum is?

If I grab my garden hose and shot a stream of water horizontally at my hood, you are telling me the water will not deflect upwards? Shouldn't water (similar to air) deflect perpendicular to the incoming angle?

It does not occur at the cowl due to high pressure zone.

The water being SPRAYED at the car will deflect in multiple directions, including upwards. Think of it as how it really is. The air is stationary and we are passing through it, rather than air spraying us. More of like jumping into a pool. The water does not deflect just one way, its stream lines around us, touching everything and filling in areas that are void.

Also shouldn't that video be more than enough proof?
 

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It does not occur at the cowl due to high pressure zone.

The water being SPRAYED at the car will deflect in multiple directions, including upwards. Think of it as how it really is. The air is stationary and we are passing through it, rather than air spraying us. More of like jumping into a pool. The water does not deflect just one way, its stream lines around us, touching everything and filling in areas that are void.

Also shouldn't that video be more than enough proof?
I was actually basing off a completely flat features hood, so I didn't really watch the entire video once I hear cowl induction hood... modeling this just as a flat / horizontal plane.
 

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Cowl induction hood is a raised reversed hood scoop. The CTR hood is flat, closer to the streamlined angle of the windshield. Cowl induction simply doesn’t happen on the CTR with the rear hood seal removed. It’s easy to conduct this test yourself with a piece of string and scotch tape (remove the rear hood seal first). My engine temperature feels lower (hand touch, post driving around town) after removing the seal; that’s good enough for me.
 
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