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CyberWolf
Dodge Dakota
7/11/2001
09:54:22
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 Subject: No Air Intake ???
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Message:
The placement of the filter on the 4.7 performance intakes seems like a stupid place. All of the companies put it right down there by the exhaust manifolds. Think back to the Chevy MAP TPI motor. Everyone removed the air intake and just put a filter right on the throttle body. They did that because it was right up front and away from the engine heat plus it eliminated intake bends. The top of the 4.7 includes aluminum heads and a composite intake. It's pretty cool up there due to this (especially if you have a cowl hood). Why not just stick a good K&N right on the throttlebody. Anyone have any thoughts on this? Bernd, what do you think?
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TEAMFAST
Dodge Dakota
7/11/2001
13:17:15
|  RE: No Air Intake ???
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This is the reason behind shaker hoods. they draw air directly from outside and eliminate intake tubes and bends. How ever you must have a kit and replacement hood for this application. As for a strictly top mounted air filter, do you have the clearance and are nt there air flow sensors in the intake tube you may eliminate by doing this?
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Kyle M.
Dodge Dakota
7/11/2001
13:52:35
| RE: No Air Intake ???
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I am running an open element on my 3.9 L V-6. At least I was, I took the plastic peice from the front of the air inlet out, located by the grille. Then I put the snorkle on and took the lid off. The 9" wide by 4" tall air filter works fine. It is like an open element and a ram air set-up in one, delivering mass flow air and cold air at the same time.
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CyberWolf
Dodge Dakota
7/11/2001
14:49:38
| RE: No Air Intake ???
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TEAMFAST,
I am very familier with the shaker hood and its an awsome design but at $800 it's a little out of most peoples range. As for clearance, the throttlebody on the 4.7 faces the front and is tilted up at about a 10 degree angle. I don't think clearance would be a problem with a conical filter. It will probably need a small adapter plate that angles the filter down a little. As far as sensors go, this engine is a MAP design, not a MAF. There are no sensors that I know of and if there are I could incorporate them into the adapter plate.
MAP = manifold absolute pressure (usually mounted to the engine)
MAF = mass air flow (usaully in the air intake)
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Bruce P.
Dodge Dakota
7/11/2001
18:54:10
| RE: No Air Intake ???
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Message:
Something to consider.
The use of a long plenum (intake tube) creates a mass of flowing air. This air mass actually RAMS air into the engine. If the tube is properly "tuned" by way of length/diamater there are benefits to having an intake tube.
Understanding the physics behind flowing fluids helps to understand this concept. ( YES...AIR IS CONSIDERED A FLUID! )
Intense performance ( http://www.intenseperformance.com ) has such an air plenum available for the 4.7L V8 Hemi. (The Z-TUBE)
Another way to think of this is to consider how properly sized EXHAUST tubes can improve power. (Header, Collector...etc) From the exhaust side it is called "SCAVENGING".
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Jeffster
Dodge Dakota
7/11/2001
19:18:05
| RE: No Air Intake ???
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Mounting an filter right on top will also suck in hot air.
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CyberWolf
Dodge Dakota
7/12/2001
09:42:52
|  RE: No Air Intake ???
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Jeffster, read the original post.
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CyberWolf
Dodge Dakota
7/12/2001
10:01:47
| RE: No Air Intake ???
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Bruce, I understand physics very well and I also know that air is a fluid. I don't belive you are correct by saying that it creates a mass of air ramming it into the engine. A tube would not create any more air at the throttle body opening. Also, I know of the Z-tube very well. Intense did not tune it to create a larger mass of air, they tuned it to create a minimum amount of turbulance. If that were the case why dont you see high performance carbureted engines with a long snorkel coming from the carb. Another thing to think about is CFM. In a non-ram air setup the throttle body will only suck a certain amount of air (CFM).
As far as the heat goes, would there be more heat down by exhaust manifolds, an iron block, and lets not forget road heat OR would there be more heat on top of the engine next to a composite intake manifold and aluminum heads? Also, if you had a cowl hood. What better place to suck in that cool air from the windshield.
Does all of this make sense? Bernd, you are the one that gave me the idea. What do you think?
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Duner
Dodge Dakota
7/12/2001
12:20:15
|  Hot Air? Tubular Man!
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The reason they snake the intake tube clear down the side like that is to make use of the cooler air coming thru the grill opening beside the radiator. The idea is to get the air that hasn't already been heated by the radiator. All of the air that is above the engine is hot. It has been heated by air coming thru the radiator (200 degrees or so) as well as heat rising from the exhaust manifold. The heads themselves give off an incredible amount of heat. The composite manifold is good for not retaining this heat, but the air up there is very hot. I taped a high-temp thermometer to my fuel rails the other day. I wanted to see how hot the fuel was getting before it got to the injectors. That fuel rail was just short of 300 degrees! Granted, it was 115 degrees outside but I got my answers. And since the fuel rail is what...8" from the TB opening? You know it's hot there too.
We tested a conical K&N filter directly on the TB opening and it slowed the truck down. Removing the air cleaner all together slowed the truck down even more! I think Bruce is onto something with the long tube statement. I can only speak for myself (my truck?), but MY 4.7 likes a long tube for the intake. The fact that it's getting cooler air from the grill opening doesn't hurt things much either. There's a definate reason those manufacturers make the long Z-tubes, and it's not just to use up material! I think in reality, with the throttle at WOT, the entire intake tube becomes just more plenum area. The 4.7 has a hard time if it doesn't see at least some vaccuum signal. With the long tube, the plenum is still under some vaccuum. At least that's my theory on it. I'm sure some "engineering" types can identify the workings better, and probably with proper terminology. All I know is "cause & effect" type of changes. I try something and see how it works. Then after the fact I try and figure out why it did or didn't work. For me, the filter directly on the TB didn't work.
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MACE
Dodge Dakota
7/12/2001
13:25:17
| RE: No Air Intake ???
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Ok, here is a question re: the z-tube and best location for the 9 inch Pro-Flow filter where I have some flexibility on where to point the front opening of the filter.
First, for maximum air-flow, physics wise, it best for un-obstructed flow through the front of this cone shapped filter, or the sides, or combination of both?
Re: the filter, should I:
1)Point it up and directly at or looking into the free space where the rubber flap behind the grill used to be (this puts it closer to the top of the engine if not above and parallel to the top). This is not a flush fit of the filter base into the z-tube.
2)Having the base of the filter sitting in flush with the opening of the z-tube which aligns the filter to be half blocked by the tranny module heat sink, angled slightly down yet being further away from the engine block.
NOTE: this is with Intense Performance's z-tube, not a custom tube where I could have a 90 degree bend for attaching the filter.
Thanks
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Duner
Dodge Dakota
7/12/2001
14:04:55
| RE: No Air Intake ???
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Unless it's a major problem to move it, I would try it both ways. My guess is that even being half blocked by the tranny module will still put it next to the cooler air that comes thru the grill opening. You should also get some air from behind the bumper, that comes thru the opening on the inside of the fender. I don't know the official scientific answer.....I'm still into the cause & effect experimentation stage.
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Jeffster
Dodge Dakota
7/12/2001
19:24:26
| RE: No Air Intake ???
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Cyber Wolfe I read the original post and feel there is still more heat up on top of the TB. All the heat from the manifolds and engine will rise to the top right under the hood. Getting a tube down to passenger side close to the removable rubber flap on the passenger side of the rad makes the most sense I think. That's what I did and am going to fabricate and alluimnium heat sheild next for even cooler air.
Later
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Jeffster
Dodge Dakota
7/12/2001
19:32:02
| RE: No Air Intake ???
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Message:
One mor thing I did a test run up my hill with no filter or air box just an open TB and it felt less powerfull than the stock box. My 4" tube leading to that cold air pocket by the removed rubber flap did feel great however but as said by others on this thread it may have to do with the ramming effect as well as the cooler air. This hole tube length and flowing air mass is really intriguing. I was thinking of even trying a super long say 6 foot tube running to wards the back just as a test.
This is a pretty cool thread that has the gears grinding.
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Bruce P
Dodge Dakota
7/12/2001
21:30:28
| RE: No Air Intake ???
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Message:
(CyberWolf)
The ramming effect is real. Many carberated engines use ram-tubes to improve flow into the carberator. An ideal ram tube has a gradual change of diamator with the largest end away from the engine. As the air column approaces the engine, the velocity gets faster and faster.
This gradual increase of velocity thru a ram-tube DOES improve the overall efficency of the intake design. This can be proven with an airflow bench and a manometer. (A vacuum cleaner and sensitive pressure-differential instrament.)
All of this intake trickery changes when the air velocity approaches sonic. (speed of sound) But that is a different physics class ;-)
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sandman
Dodge Dakota
7/12/2001
23:17:06
| RE: No Air Intake ???
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Message:
Duner you are on the right track with the vacum theory. You want to hold peak vaccum as long as possable. You want to allow the engine to produce a partial vacum so that the air is pushing into the engine as much as it is being pulled in. Vacum is so important to an engine that Nascar has to limit the size of the pump used to evacuate the oil pan or teams would put larger and larger pumps on to gain more negative pressure in the engine. Honda gained significant power 100hp in F1 by redesigning there crank case to create a greater vacum. Think of it as the obaset of super chargeing an engine. Instead of forceing air into the egine you are sucking all the air out of it so that the air will rush into it under pressure because of the variance between the two presures.
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sandman
Dodge Dakota
7/12/2001
23:18:24
| RE: No Air Intake ???
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Duner you are on the right track with the vacum theory. You want to hold peak vaccum as long as possable. You want to allow the engine to produce a partial vacum so that the air is pushing into the engine as much as it is being pulled in. Vacum is so important to an engine that Nascar has to limit the size of the pump used to evacuate the oil pan or teams would put larger and larger pumps on to gain more negative pressure in the engine. Honda gained significant power 100hp in F1 by redesigning there crank case to create a greater vacum. Think of it as the obaset of super chargeing an engine. Instead of forceing air into the egine you are sucking all the air out of it so that the air will rush into it under pressure because of the variance between the two presures.
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Duner
Dodge Dakota
7/12/2001
23:24:02
| RE: No Air Intake ???
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Message:
Thanks Sandman,
At least that's how I'm trying to think of it. The longer tube acts like a vaccuum reservoir for the plenum. Somewhat how a boost bottle works on a 2-stroke.
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Jeffster
Dodge Dakota
7/12/2001
23:45:54
| RE: No Air Intake ???
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Hmmm. The question I have is this. Is my 4" intake tube with a smooth taper down to 3" at the TB a good thing. I know for a fact it's better than the stock box I can feel it. I am hoping my 4" tube is generating a moving mass that is quickly speeding up as it hits the taper at the TB. I also have a feeling that because mine is 4" it should also be proportianetly longer than a 3" tube but who can really say for sure. If I had the time and money I would fabricate a 3" and dyno test both but they want to much for dyno pulls out where I am. $70.00 CAN per pull. I guess I will hope I am getting a quick surge at the TB. The suction was tremendous at the end before I got the fliter on it. Could suck your hand in so I think it's probably doing what I want.
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Duner
Dodge Dakota
7/12/2001
23:52:43
| RE: No Air Intake ???
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I have a dyno session scheduled for next wednesday morning. I hope to answer some of my own questions in a more controlled setting. It's really hard to tell exactly what helps and hinders at the race track because there are so many variables. The cost here is $75.00 per 1/2 hour. I'm hoping to get 4 pulls in that amount of time....5 if I hustle. I can switch air cleaners, tubes and throttle bodies pretty quickly if it costs me money!
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Jeffster
Dodge Dakota
7/13/2001
00:17:28
| RE: No Air Intake ???
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Excellent news Duner. I hope you will share your results. I wish I live near you and I could bring my >mongo intake system< and split the cost.
BTW I noticed Dapurple had located his IAT sensor on the tube. I assume to fool it into think the temps were colder and trick the PCM. Do you know if he got any significant results. I am sure I could do the same to my >mongo intake system<
Later
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Duner
Dodge Dakota
7/13/2001
00:35:50
| IAT Adjustor Box
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I moved my IAT on my R/T and it was good for some improvement. But here in Phoenix, anywhere under the hood is going to produce high temperatures.
I'm running the IAT adjustor box on my 4.7 and it works very well. My truck likes a setting that is way cooler than the IAT would see just by being relocated. It's a pretty neat deal. You can crank the knob and notice a change in the engine tone. It helps keep my truck from feeling as doggy as it would normally feel in the heat. It doesn't seem to change much at WOT, but at mid-throttle, it improves the throttle response and improves accelleration.
I highly recommend it.
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Jeffster
Dodge Dakota
7/13/2001
02:35:45
| RE: No Air Intake ???
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I may do it that later. I think for now I will try and relocate it right up towards the front of my tube where it is significantly cooler.Living on the west coast of Canada should get me some nice track times and the air is much cooler so I think it will be effective. Our 1/4 mile strip is at sea level and evening temps can dip into the mid 60's. They also have a compound layed down that give great traction. Apparently some worlds records have been set on this track but I am not sure for what. If these damn computers don't want to play ball I guess we will just have to try and fool them as best we can.
I am very unimpressed by the prospects of PCM flashes and the Jet chips right now. I am hearing of gains of 15 to 20 HP which seems way under what should be obtained especially when you consider you are running supreme and not reg.
Is there a better solution to the computer issue than these half fixes. I saw on T.V some ricers actually using there portable PC's to control there engines performance. Has anyone gone to this extreme.
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surferpug
Dodge Dakota
7/13/2001
03:55:58
| RE: No Air Intake ???
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would a helix type intake help? I just purchased an airmax cold air intake and I noticed the inside of the tube is helixed to swirl the air
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CyberWolf
Dodge Dakota
7/13/2001
09:51:45
| RE: No Air Intake ???
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Thanks guys. It's good to know that someone tried it and it didn't work. What gave me the idea was talking to Bernd about cowl induction. As I said before, I think the cowl would eliminate the heat problem on top of the engine. A cowl is supposed to pull cool air in from the windshield and it does work. Thats why I figured it might not be a bad idea to run a filter attached straight to the throttle body. That would put the filter right underneath the opening of the cowl. Think of all the cool air I could feed my filter in that position.
As I stated before, one of the main problem for the performance companies that make air intakes is turbulance. They do all of those wierd bends to get rids of the turbulance which in turn would speed the air flow. One thing I did not think about and may be the reason that a power loss was experienced is that a filter attached directly to the throttle body would probably cause a lot of turbulance. This is a problem with carbureted engines and that is where air horns fit in. A long tube with engineered bends probably smooths the air out creating a lot less turbulance.
Thanks everyone for your help and ideas. It brought up a lot of good questions and hopefully even made people think a little.
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MACE
Dodge Dakota
7/13/2001
10:18:58
| RE: No Air Intake ???
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Ok, group thought on where the coldest part of the engine bay is:
Bottom, even though the exhaust manifolds are there?
Or top, near the heads/valve covers?
Yep, we all know heat rises, but would it really be 'cooler' by the exhaust manifolds in re: as to where to point a z-tube filter?
And should I want all the fresh air to hit the opening of my 9 inch Pro-Flow filter, or fresh air to the sides, work as well?
Thanks.
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CyberWolf
Dodge Dakota
7/13/2001
11:29:03
| RE: No Air Intake ???
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I was figuring the top would be the coolest with a cowl hood. Without a cowl it would probably be up front where the z-tube puts the filter, especially with the rubber flap removed.
As far as filters with an open front:
K&N tried this a while ago. They found that filters with an open front flowed less than filters with a closed front. They quickly quit making open front filters. They explain why on their web site somewhere.
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MACE
Dodge Dakota
7/13/2001
13:11:06
| RE: No Air Intake ???
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I took apart my z-tube, cleaned the filter and re-installed, with the filter facing as far forward as possible and as for down as possible, this way when sitting still, I'm not getting all the heat that is rising, and when moving, what ever heat coming from the manifolds, should be pulled to the rear or firewall.
Have it so it gets cold air from the front with the rubber flap removed and cold air from the side from fender well's small openings. (toyed with relocating the the tranny module heat sink but didn't)
For Intense Peformance's new 9 inch Pro-Flow filter, it's pretty cool looking...it is a open faced filter with that opening tappering into a closed off cone shape within the main body of the filter, looks like it injects air into the main body of the filter, so you have air flow from the front pushing air flow from the side, down the filter and into the tube.
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CyberWolf
Dodge Dakota
7/13/2001
14:06:14
| RE: No Air Intake ???
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K&N says that the conical shape opening on the front of a filter decreases the amount of air the filter can intake. They say the reason is that the intake tries to pull all of the air through the front of the filter. The air coming through the front of the filter causes sort of an equilibrium and will not suck air from the first 3/4 of the filter. That leaves only the front and the rear 1/4 of the filter sucking air. After that it all comes down to filter area. The area of the filter that actually sucks air without the open front is larger than the area that would be used if it had an open front. That is why K&N sold this type of filter for only a couple months and currently has nothing like it in their extensive line of filters. They strongly recommend not using a filter that has an open front.
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MACE
Dodge Dakota
7/13/2001
14:17:30
| RE: No Air Intake ???
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If you ask me, it's all about advertising.
Any other manufacture make the same statement or stop selling open front cone filters? How long ago did K&N do this?
The Pro-Flow has only been out for about 1 month, seems hard to believe they would use old technology or something that doesn't work the best, for their newest product. Perhaps K&N didn't like their statement that the IP filters outflow the K&Ns and they yanked the product as they didn't want to spend more money on R&D?
Whatever, I like my setup for the performance and sound, perhaps the large size of the filter makes up for the shortcomings K&N claims.
BTW Cyberwolf, you've probably posted this before, are your running a cold air intake, and if so, what brand, type/size of filter?
Thanks.
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CyberWolf
Dodge Dakota
7/13/2001
16:16:25
| RE: No Air Intake ???
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Actually, I met a guy that created a Ram air setup for the R/T. He used to work for Mopar. He went off on his own designing this ram air system for the 5.9. His shop has a flow bench and all sorts of other cool things. He figured out some way to increase the psi from a normal ram air system, somehow. Anyway, he is using my truck for a 4.7 setup. He is extremely busy with this 5.9 setup right now though so I'm kinda sittin idle waiting for him.
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surferpug
Dodge Dakota
7/13/2001
17:57:48
| RE: No Air Intake ???
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I noticed that some of you have MSD ignition wires, does anyone have them on a 4.7L?
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lattimer
Dodge Dakota
7/13/2001
18:22:26
| RE: No Air Intake ???
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Regarding open front filters:
What happened with the K&N design is a true statement. The air coming in the end of the filter actually causes a pressure wave that stagnates the air coming in from the sides. So in this situation, you effectively have less surface area for air to enter. However, when you place the open face filter where it intakes air fromoutside through the open area, you will see more of a ram air effect as your speed increases.
Pro-Flow probably designed their filters in such a way as to avoid the stagnation effect. Its all about the angle of the mesh and the relative surface areas.
Shawn
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CyberWolf
Dodge Dakota
7/17/2001
09:18:17
| RE: No Air Intake ???
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Bernd,
I'm curious what you have to say about running a K&N cone filter directly attached to the throttle body. Especially with a cowl hood like ours. I saw a post back in January where you were talking about running an open element on the magnum engines. Any thoughts on this?
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JEFFRO
Dodge Dakota
7/20/2001
14:37:00
|  RE: No Air Intake ???
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WHERE EXACTLY IS THE IAT. ARE THE ADJUSTMENTS THAT YOU ARE TALKING ABOUT AS EASY AS TURNING A KNOB? IF SO THAT IS GREAT. IF ANYBODY KNOWS OR CAN HELP PLEASE LET ME KNOW BECUASE I AM OUT TO KILL MUSTANGS. IT STAYS ON AN AVERAGE OF 80'S TO 90'S.
THANKS
JEFFRO
2000 RC 4.7L
AUTO 3.55 ANTI-SPIN
HOMEBREW INTAKE
STRAIGHT DUAL EXHUAST
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CyberWolf
Dodge Dakota
7/20/2001
17:00:59
| RE: No Air Intake ???
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SpeedTweaks makes an IAT adjuster and it yes, it is as easy as turning a knob. Click on a SpeedTweaks link at the top of any of these pages. He has a ton of info about it on his web page. The IAT is in the intake manifold.
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Dr. Q
Dodge Dakota
7/25/2001
23:31:32
| RE: No Air Intake ???
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I was looking into this Z-tube buisness and a couple of things occured to me.
1.)The amount of flow is directly propotional to length X radius to the FOURTH power. (if you double the length you half the flow. But if you half the radius you get 1/16 th amount of flow and vice versa.
2.) vacuum and spark advance-isn't the engine computer tuned to run at a certain spectrum of vacuum and would mucking with the amount of airflow mess with the tune and air fuel mixture.
3.)This tuned length malarkey the place of maximum turbulence is going to be directley behind the trottle body and wouldn't the voluume of air be directly proportional to the the radius of the surface area of the opening of the valve.
4.)It would seem that if your goal is to increase air flow to the engine without letting particles and a whole bunch of crapola get into your engine would be to increase the surface area of the filter---kinda like the big old box that came with the truck in the first place.
I'm not Joe mechanic and I mabe AFU, but I do know a little about physics. But if some after market sale rep wants to buy a boat based on the commission from some doo dad he's just about to say anything. (Ever see those deals that "align" the molecules of gasoline?) But if the numbers don't add up they don't add up.
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Duner
Dodge Dakota
7/26/2001
01:55:33
| Physics Lessons?
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Dr. Q
1. What does all of your formulas and fluid dynamics say about the stock system's 90 degree bends and sharp angles? Can it be improved upon?
2. Isn't messing with the stock factory tuning the whole idea? Afterall, I gained 50% better fuel mileage and increased my hp & torque all at the same time by "messing" with the factory tuning.
3. We're talking about increasing the plenum area by using the long tube. When the TB is at WOT, the engine only knows how much flow versus vaccuum it sees. There is turbulance, but why is a tube before the TB better than no tube at all?
4. The big old box (air cleaner) that came with the truck in the first place is designed for ease of construction and made to accommodate all of the engines that they use. If you look at the surface area of the flat panel filter and compare it to a large cone or circular filter, you can see that it is much smaller in surface area. The 3.9L, 47L and 5.9L engines all require different amounts of air at their maximum rpm limits but they all use the same air filter system.
You sound like you have a good grasp of math and physics.....
How much clean filtered air does my287 cubic inch engine require at 6000 rpm. How much vaccuum (intake restriction) does that same engine want or like to see while it's flowing all that air thru it? Why wouldn't my engine work better with a 2000 cfm throttle body? Why wouldn't my engine work better with a 200 cfm throttle body? What would the difference be? Why would it make any difference whether there was a vaccuum signal or not? Isn't airflow just about radii and turbulance versus tube size and velocity? Why does it make any difference what size plenum an engine has? Why would the length of the intake runners make any difference? How does an engine respond to changes in back-pressure in the exhaust?
I'm sure you know about 500 times more about physics than I ever will. Show us how much you know about tuning an engine for best performance. And don't tell me the engineers at DC have already done as good as it's gonna get......we all know better than that one.
Duner
Lives for Tuning Answers
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Dr.Q
Dodge Dakota
7/26/2001
06:02:20
| RE: No Air Intake ???
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Like I said I'm not Joe mechanic. But, the thing that was confusing me was that after most folk on the board had spent their money on the z-tube the only reported negligable improvements in HP-but it looked good. After looking at the setup it appeared that the point that was the limiting factor in the airflow wasn't the air intake but the throttle body.
I'll be the first to fess up about my ignorance in tuning an engine that's the whole reason I wrote in the first place. But you seem to be the expert and if you'd share your wisdom I would really appreciate it. If you want to know which would be the appropiate treatment for meningitis is, mabe I can help. But If you could 'splain this stuff to me like I'm four I'd appreciate it.
Also this back pressure deal? They've got these new catalytic converters on the '01 4.7 right? So the only way to "legally" modify your exhaust would be to modify the exhaust from the cat back. How much difference would it make at that point? I mean is the pressure drop from the cat to the tip worth spending good money on. I could understand theory behind putting headers on and a larger diameter exhaust to improve flow and reduce back pressure, but is seems that DC has got you by the short and curlies with this restricive exhaust choking flow through 3/4's of the system!
Don't take what I'm talking about here wrong but I've been looking at all this after market stuff and frankly the last person I'm gonna trust with my money is someone trying to sell me something. I love the truck but hate salesmen. Know what I mean?
AND finally Duner! How the heck did you get a 50% increase in MPG's. 'Cuz frankly dude I'd be needing an increase in MPG's long before I'd be needing more HP's I mean how often do you go running WOT, 'cuz fess up even stock this here truck is a lot of fun.
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Doug McCoach
Dodge Dakota
7/26/2001
10:29:28
| RE: No Air Intake ???
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Message:
Dr Q. I too have an educated background but would hardly say I am an expert in any of this. However,
after driving myself insane for a week trying different homemade air intake systems, I learned one thing, a high flow filter improves air flow & sounds neat but does little for performance gains. If you read articles on the airaid systems & others its clear you gain a few ponies in the process but the one thing that dramatically improves hp is cold air. It didn't matter if I was using a bored out branch from my back yard tree, if the incoming air was cold, it generated more power. My truck ran better on a cold evening with a stock air intake/dirty paper filter, than it did with my best home made air intake attempts on a hot day. The super charger is one of the best hp/dollar upgrade available. The only problem is it costs $4000 for the 4.7L V8 & that is too much for most family men. Hopefully in a few years the price will come down, maybe $2000. Anyway, as I listen to arguments about needing vacuum to maximize flow/hp/torque, if you think about the stock airhat, it has two chambers that divert incoming air that doesn't flow into the tb. This creates a vacuum that was designed/intended by Chrysler? If it is for marketing purposes like
many people say, wouldn't they want to save money & make a more efficient looking/performing
system? I haven't met one person who says he bought the 4.7L V8 because of the cool looking air hat. Also, if you leave a stock air filter in the stock air intake, you'll notice that only a small portion of the airfilter gets dirty-the air is taking the least path of resistance & forms a tunnel shape to do so. The big old air box allows more air to sit thus creating a vacuum. Why else would they make it so darn big, it certainly doesn't improve air flow when the inlet is only a few inches in dia. Sorry if I sound like I am an
expert, I just wanted to get people thinking about this. Also, wouldn't it be great if we could get a DC engineer to defend why the stock intake looks the way it does!
2000 QC 4x4 Auto 3.55's 4.7L V8
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CyberWolf
Dodge Dakota
7/26/2001
11:07:02
| RE: No Air Intake ???
IP: Logged
Message:
Well, you people have put a lot more thought into this than I ever did. So after all of this, what would be better;
An intake tube that places the filter lower and to the front? or
A filter attached straight to the throttle body which is directly below the hole in my cowl hood.
I have a lot more mechanic ability than scientific. I would think that It would be better with no intake because it is a shorter path. Also with cold air coming in off of the windshield from my cowl hood it seems that the air supply would be colder. What do you scientists think? (in words that I can understand)
Thanks
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