Re: The "myth" of ram air.. does it WORK in cars/trucks?
[Re: 360view]
#2048136
04/06/16 04:34 PM
04/06/16 04:34 PM
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Joined: Jan 2003
Posts: 28,114 Irving, TX
feets
Senior Management
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Senior Management
Joined: Jan 2003
Posts: 28,114
Irving, TX
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Past threads about tailgate up or down Have sadly gone down the path of this one.
What if you leave the tailgate down on your treadmill?
We are brothers and sisters doing time on the planet for better or worse. I'll take the better, if you don't mind. - Stu Harmon
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Re: The "myth" of ram air.. does it WORK in cars/trucks?
[Re: dvw]
#2048501
04/06/16 11:24 PM
04/06/16 11:24 PM
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Joined: Jan 2003
Posts: 6,591 Canton, Ohio
Sport440
master
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master
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Posts: 6,591
Canton, Ohio
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id you ever stick your hand out the window while running at 60 mph? What did it do, just sit there? I think not. Doug My hand didn't do a thing till about 230 mph, then oh yeah, felt the boost. Just did it, nothing before that though, strange???
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Re: The "myth" of ram air.. does it WORK in cars/trucks?
[Re: AndyF]
#2048510
04/06/16 11:33 PM
04/06/16 11:33 PM
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Joined: Jan 2003
Posts: 6,591 Canton, Ohio
Sport440
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Canton, Ohio
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Just hook up a manometer to an air box and you'll see that it generates positive pressure even at highway speeds. That is all the proof that you need.
Here is the graph of dynamic pressure relative to speed. A well design air scoop should be able to capture most of this pressure. I think this chart comes from Moparts member Mark W. Ram air is indeed beneficial all over in all engine related performance builds, across all, industries.
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Re: The "myth" of ram air.. does it WORK in cars/trucks?
[Re: Sport440]
#2048606
04/07/16 04:02 AM
04/07/16 04:02 AM
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Joined: Mar 2011
Posts: 1,662 Cut and Shoot, TX
kentj340
top fuel
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top fuel
Joined: Mar 2011
Posts: 1,662
Cut and Shoot, TX
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I'll bet 99% of forum members already knew that hood scoops and cool air ducts improve performance by only a small amount in real world driving.
Since lots of people think scoops look sexy, they aren't going away anytime soon, which will no doubt keep discussions like this one going.
Every NASCAR car that I have seen up close was getting intake air from the bottom of the windshield by way of a carbon fiber air box from the firewall to the carb. I'm pretty sure each and every NASCAR car has these air boxes that feed the carb cool air and supposedly higher pressure air that piles up at the bottom of the windshield at high speeds.
If you don't see two dolphins, you need a vacation.
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Re: The "myth" of ram air.. does it WORK in cars/trucks?
[Re: cudaman1969]
#2048878
04/07/16 02:07 PM
04/07/16 02:07 PM
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Joined: Dec 2003
Posts: 23,554 Here
jcc
No soup for you!!!
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No soup for you!!!
Joined: Dec 2003
Posts: 23,554
Here
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Hood scoops slow them down, stick your hand out the window at 60 mph, now at 200, still got a hand? Benefit of scoops are less than the drag it produces, so they use the cowl, no drag and good results. NASCAR from day one said they where not allowed. You are implying exactly what? And are you going to share your idea of why from the get go (1959?) why Nascar has never allowed hood scoops on "stock" cars? Or why NHRA has recently restricted them on Pro Stocks? I agree, this never ending thread needs to be renamed "Moparts Mythbusters".
I'm with Helmuth Hübener, and no soup is being served today.
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Re: The "myth" of ram air.. does it WORK in cars/trucks?
[Re: DARTH V8Я]
#2049055
04/07/16 05:26 PM
04/07/16 05:26 PM
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Joined: Nov 2011
Posts: 2,154 Its a TRAP!
DARTH V8Я
OP
Oh No!! I just had a moron attack!
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OP
Oh No!! I just had a moron attack!
Joined: Nov 2011
Posts: 2,154
Its a TRAP!
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Wow.. this is turning into the "can a propeller plane take off from a conveyer belt" fiasco.
Maybe Mythbusters can say confirmed/busted lol. Oh but they ain't on the air anymore..
When it takes more than a sweet mullet to prove you rule at the trailer park..
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Re: The "myth" of ram air.. does it WORK in cars/trucks?
[Re: DARTH V8Я]
#2049273
04/07/16 09:30 PM
04/07/16 09:30 PM
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Joined: Jan 2011
Posts: 4,785 Utah and Alaska
astjp2
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Utah and Alaska
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Every airplane in the world uses a Pitot tube which is ram air to move a gauge. You are using aerodynamic concepts for compressibility in front of an airfoil. Wrong use of application, but hey what do I know? I have only worked on everything from a 747 to an F-15 to a UH-1 to a super cub..... http://www.luizmonteiro.com/Article_Pitot_Static_Blockages_02.aspx Why are you so hung up on 230 mph? The air molecules don't know how fast the hood scoop is going. It isn't like they look at a car and say "it is only going 210 mph so we're not jumping in".
The pressure in a hood scoop will increase with the square of the velocity starting from zero. It isn't a light switch that turns on at 230 mph. There will be positive pressure (greater than 14.7 psi) at any speed above zero. The equation was posted back on page one of this thread. Well it's just the fluid dynamics theory. That's all. Show me the contrary proof that ram air can give positive pressure. Again, great conversation (some notable exceptions however).
Last edited by astjp2; 04/07/16 09:34 PM.
1941 Taylorcraft 1968 Charger 1994 Wrangler 1998 Wrangler 2008 Kia Rio 2017 Jetta
I didn't do 4 years and 9 months of Graduate School to be called Mister!
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Re: The "myth" of ram air.. does it WORK in cars/trucks?
[Re: DARTH V8Я]
#2049282
04/07/16 09:36 PM
04/07/16 09:36 PM
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Joined: Jan 2011
Posts: 4,785 Utah and Alaska
astjp2
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Wow.. this is turning into the "can a propeller plane take off from a conveyer belt" fiasco.
Maybe Mythbusters can say confirmed/busted lol. Oh but they ain't on the air anymore.. actually it can. coming from someone who landed on a moving freight train...
1941 Taylorcraft 1968 Charger 1994 Wrangler 1998 Wrangler 2008 Kia Rio 2017 Jetta
I didn't do 4 years and 9 months of Graduate School to be called Mister!
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Re: The "myth" of ram air.. does it WORK in cars/trucks?
[Re: cudaman1969]
#2049550
04/08/16 09:48 AM
04/08/16 09:48 AM
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Joined: Dec 2003
Posts: 23,554 Here
jcc
No soup for you!!!
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No soup for you!!!
Joined: Dec 2003
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Here
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"And are you going to share your idea"
Nah, look it up, I did The complete question was "And are you going to share your idea of why from the get go (1959?) why Nascar has never allowed hood scoops on "stock" cars?" Then care to share what you looked up, and what you discovered, and your source, like a grown up? You likely will find that "Nascar" adhered to the philosophy of maintaining a stock appearing car like the paying spectator drove in the late 50's, and hood scoops were not part of that look, I suspect the tradition took hold thru till today on hood scoops. Aero concerns of turbulence of air scoops was not on the radar back then in stock car racing. The cowl intake solution was a clever successful later work around.
I'm with Helmuth Hübener, and no soup is being served today.
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Re: The "myth" of ram air.. does it WORK in cars/trucks?
[Re: DARTH V8Я]
#2049699
04/08/16 01:18 PM
04/08/16 01:18 PM
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Joined: Nov 2011
Posts: 2,154 Its a TRAP!
DARTH V8Я
OP
Oh No!! I just had a moron attack!
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OP
Oh No!! I just had a moron attack!
Joined: Nov 2011
Posts: 2,154
Its a TRAP!
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The cowl intake solution was a clever successful later work around. According to Chevrolet, they couldn't figure out why there Chevrolets were slowing down as the race wore on and the Pontiacs were faster with 25 less horsepower. It was determined that the Pontiacs engine bays were running 20-30* cooler than the Chevrolets. After some experimentation at Daytona speedweek, the NASCAR cowl induction was born. Just so happens Popular Hot Rodding magazine did a test with a NASCAR style cowl induction: "One thing to keep in mind is that this sort of induction doesn’t really offer any true ram effect, and, in fact, most ram-air-style systems don’t either until very high speeds—and even then the pressure increase is pretty negligible. Since cooler air is denser air, and denser air makes more power, the real goal is to provide the engine with an easy source of the coolest air possible."
When it takes more than a sweet mullet to prove you rule at the trailer park..
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Re: The "myth" of ram air.. does it WORK in cars/trucks?
[Re: DARTH V8Я]
#2049901
04/08/16 05:26 PM
04/08/16 05:26 PM
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Joined: Jan 2003
Posts: 8,245 Plymouth, MI
Blusmbl
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Plymouth, MI
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Well, it's clear astjp2 won the thread with an actual graph of pressure vs. airspeed.
'18 Ford Raptor, random motorcycles, 1968 Plymouth Fury III - 11.37 @ 118
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Re: The "myth" of ram air.. does it WORK in cars/trucks?
[Re: Blusmbl]
#2049989
04/08/16 07:41 PM
04/08/16 07:41 PM
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Joined: Dec 2003
Posts: 23,554 Here
jcc
No soup for you!!!
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No soup for you!!!
Joined: Dec 2003
Posts: 23,554
Here
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Well, it's clear astjp2 won the thread with an actual graph of pressure vs. airspeed. Be careful with that conclusion, there have been graphs shown by parties here with opposing views, interpreting the graphs is the key. I'll try to find the graph of protagonist "certainty" vs intelligence. PS read my sig link.
I'm with Helmuth Hübener, and no soup is being served today.
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Re: The "myth" of ram air.. does it WORK in cars/trucks?
[Re: jcc]
#2050025
04/08/16 08:53 PM
04/08/16 08:53 PM
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Joined: Jan 2011
Posts: 4,785 Utah and Alaska
astjp2
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Utah and Alaska
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Well, it's clear astjp2 won the thread with an actual graph of pressure vs. airspeed. Be careful with that conclusion, there have been graphs shown by parties here with opposing views, interpreting the graphs is the key. I'll try to find the graph of protagonist "certainty" vs intelligence. PS read my sig link. So you are saying that every aircraft that uses an airspeed indicator is wrong? Or that my graphic is bad data? That is where those numbers come from. The size of the opening does not change the pressure either, a 1/4" pitot and a 3" have the same pressure, the larger one has more overall force because of the cross section but the pressure inside is the same. Tim
1941 Taylorcraft 1968 Charger 1994 Wrangler 1998 Wrangler 2008 Kia Rio 2017 Jetta
I didn't do 4 years and 9 months of Graduate School to be called Mister!
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Re: The "myth" of ram air.. does it WORK in cars/trucks?
[Re: astjp2]
#2050027
04/08/16 08:56 PM
04/08/16 08:56 PM
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Joined: Dec 2003
Posts: 23,554 Here
jcc
No soup for you!!!
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No soup for you!!!
Joined: Dec 2003
Posts: 23,554
Here
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Well, it's clear astjp2 won the thread with an actual graph of pressure vs. airspeed. Be careful with that conclusion, there have been graphs shown by parties here with opposing views, interpreting the graphs is the key. I'll try to find the graph of protagonist "certainty" vs intelligence. PS read my sig link. So you are saying that every aircraft that uses an airspeed indicator is wrong? Or that my graphic is bad data? That is where those numbers come from. The size of the opening does not change the pressure either, a 1/4" pitot and a 3" have the same pressure, the larger one has more overall force because of the cross section but the pressure inside is the same. Tim No, what I saying is, blind faith in graphs(?) is what started this train wreck, blind faith is the problem, not the graphs.
I'm with Helmuth Hübener, and no soup is being served today.
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