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Ram-Air upgraded again (pix)

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Old 03-15-2004 | 03:23 PM
  #41  
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Originally Posted by spirilis
That was a decent read. I don't know jack about fluid dynamics, so I can't verify what it says, but it sounds good enough to me.

I think one thing this "ram-air" intake can provide is constant access to fresh cold air. That alone should be motivation for building such a thing.
I would say that the biggest error in the piece was the statement in bold/italics below:

"There are two ways to increase the pressure and density of the air inducted into the cylinders:

- Decrease the pressure drop from the throttle plate to the cylinders

- Increase the starting pressure at the throttle plate.

Ram air is an attempt to do the second"
IMO Ram Air actually can address both, theres the big disconnect and if you believe what he says, that Ram Air only tries to pressurize the intake air, then its easy to believe that it doesnt do much. However, I have taken the attitude that Ram Air actually can do alot for #1 and a little for #2. Just my opinion but I went into what I thought was a pretty decent justification...

EDIT: And when I say "a lot for #1" I mean it does alot compared to what it does for bullet #2.
Old 03-15-2004 | 03:45 PM
  #42  
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Originally Posted by Spaniard
Its all good- Nothing wrong with the discussion IMO... Maybe I got a little defensive so my bad. I feel more educated from it so thanks are more in order than anything else

One thing that occurred to me- if there is a way to get a reading off of that boost sensor (im not an electronics person but I imagine there might be a way to wire it to some electical thingie) then perhaps that is the best test possible... Just look at the readout at different speeds (like 70,80,90...)

Im heading out to take a closer look at that doo-hiky
wa ter man om et er
Old 03-15-2004 | 03:57 PM
  #43  
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Originally Posted by bluemaxx
wa ter man om et er
I dont know what these things look like or how they work, so I am kinda clueless about how to incorporate it... like-

Would I want it like in my intake pathway?
Will it retain its readings after the drive? (I doubt this- so I need to be able to see what it 'says' while speeding down the freeway... kind of daunting)

??
Old 03-15-2004 | 04:03 PM
  #44  
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Ah, I got a look at one.. Good idea.. perhaps I can use that port that comes off the midpipe for a reading...


Old 03-15-2004 | 06:16 PM
  #45  
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Originally Posted by Spaniard
Ah, I got a look at one.. Good idea.. perhaps I can use that port that comes off the midpipe for a reading...


Yes, the brass nipple in your picture. Don't hook it to anything between the throtle blade and the engine, engine vacuum will suck the water right out of there. A U-tube, water manometer is a fairly crude instrument so no, you won't be able to "save" your results. You can install a check valve between the nipple and the manometer to make your peak result stick but the smallest ones that I know of are designed to operate at greater than 3" water column. Less than 3" and you won't even open the check valve. I don't think you'll be able to generate that kind of presure but I guy can dream can't he? Good luck.
Old 03-15-2004 | 11:09 PM
  #46  
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Originally Posted by bluemaxx
Yes, the brass nipple in your picture. Don't hook it to anything between the throtle blade and the engine, engine vacuum will suck the water right out of there. A U-tube, water manometer is a fairly crude instrument so no, you won't be able to "save" your results. You can install a check valve between the nipple and the manometer to make your peak result stick but the smallest ones that I know of are designed to operate at greater than 3" water column. Less than 3" and you won't even open the check valve. I don't think you'll be able to generate that kind of presure but I guy can dream can't he? Good luck.
Thanks Bluemaxx... Getting a manometer... Chances are I wont be overjoyed with the results but at least its better than not knowing..
Old 03-16-2004 | 11:41 AM
  #47  
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I'd have to say I don't know what's worse, you're homemade ram-air setup or that tire rack logo on your windshield
Old 03-16-2004 | 03:48 PM
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Originally Posted by andymax95
I'd have to say I don't know what's worse, you're homemade ram-air setup or that tire rack logo on your windshield
(YAWN)

well, I bet if you concentrate really hard and think about it for a really long time you can figure it out.
Old 03-17-2004 | 01:20 AM
  #49  
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i don't get why you guys are making this into a such complicated thing! perhaps there's no exact # of gains spaniard got from this ram air thingy, maybe his airflow diagram isn't at the optimal setup, but there is COLD air inducting to his intake path. at least from the way i see it, it is a fact to me.

if he's got more air flow into his intake system, i don't see why he won't pick up some horses from there. well..exact how much horses? i don't know. but he said he felt a difference, so give the man credit for that.

that's just IMO. i attempt to think in simple term.
Old 03-17-2004 | 08:43 AM
  #50  
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i think it's the phrase "ram-air" that's causing all the hullabaloo. simply calling it a "modified cold air intake path blah blah blah" would be a lot more acceptable to most that have disagreed.

I agree with happyricefob in the aspect of cooler air going into the bay....passing cooler air into the engine bay *directly* is a lot more effective than using the hot air in the bay plus supplemental air that has somehow meandered into the bay from everywhere else.....and I don't know jack about engines so I may be wrong.
Old 03-17-2004 | 10:05 AM
  #51  
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Looks like the front of your car should say HOOVER.

Seriously though, your main impediment will be your airbox, filter and the tubing to get to your throttle body.

If you care about function over form, why not cut a scoop in your hood and relay the air directly to the throttle body (with a high flow filter)?
Old 03-17-2004 | 10:07 AM
  #52  
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don't hate.

innovate
Old 03-17-2004 | 10:26 AM
  #53  
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Originally Posted by 2002 Maxima SE
Looks like the front of your car should say HOOVER.

Seriously though, your main impediment will be your airbox, filter and the tubing to get to your throttle body.

If you care about function over form, why not cut a scoop in your hood and relay the air directly to the throttle body (with a high flow filter)?
NOW THATS WHAT IM TALKIN ABOUT!! Good idea. Well, actually a bit aggressive for today's project.

But it gives me food for thought for sure!

Oh, and on the manometer subject-

I was talking to a friend about measuring the intake air pressure (w/ the manometer at the midpipe)
Be both think that realistically Im not going to find pressurized air there. (Im holding out hope that I might find slightly pressurized air at very high velocity and minimal throttle in high gear- as this would be ideal conditions for it to happen)

BUT- (this made alot of sense to me) It would be a BIG WIN to find that there was NO Vaccum (negative pressure) -even at WOT-(Possibly even at high RPM) at high speeds. (the neg pressure from the engine operation, eh!)

Anyone see it this way too?
Old 03-17-2004 | 10:57 AM
  #54  
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Originally Posted by Chinkzilla
If nothing else, it blows cold air on the filter element. It probably can't create positive static pressure but it sure as hell can reduce the vacuum. I think the thing we're missing here is that it's not all about positive pressure. Also, any knowledgable turbo guy will tell you it's not about PSI it's about CFM.
Exactly!!
Old 03-17-2004 | 04:02 PM
  #55  
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The answer is “divergent”. Yes, the nozzle would have to shaped so that the skinny end is pointed into the air stream, and the fat end connects to the throttle plate. How can this be right? Remember, to increase the static pressure of the intake air (which is the true “ram air” effect), the kinetic energy of the air must be traded to compress the air. This is done by slowing the air down, or stagnating it, and the only way to do this is with a diverging nozzle. Ah, but since air is incompressible at automobile speeds, it doesn’t matter any way.

Taken from the article mentioned a few posts ago. Air is a compressibly substance, water is incompressible. Unless I'm misinterpreting what the writer is saying, air is compressible at low speeds (of course I dont take fluid mechanics until next semester...) but regardless, in order to increase air pressure, you need a "cone" with the small end facing the incoming air, and the large end facing away (in our case the throttle body). Placing the scoops the other way will increase velocity of the air, but decrease the pressure. Its opposite as to what you might think. However, while there wont be any pressure increase, you are getting a nice big supply of outside air. That is where the power comes from, not a "pressurization" of air.
Old 03-18-2004 | 01:50 AM
  #56  
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Originally Posted by bluemaxx
...BTW, I was/am in no way dissin' your efforts. They laughed at the Wright brothers too, and you know how that turned out.

Didn't they crash? (atleast the first time or two)

I give props to Spaniard for trying to better his car. I also think there is logic on both sides of the argument, but I tend to side with Spaniard's logic. Keep in mind I'm trying to remember my Physics classes, and when I had them, we were busy laughing at this Bill Gates guy who thought computers needed a GUI. Geez, the nerve of some people to improve on things. I actually learned to program in BASIC, as our machines operated from 5 1/4" disks.

Spaniard is trying to improve his car's performance. Whether it works remains to be seen (a few controlled 1/4 miles would be nice to get some data). But I think his idea is a lot better than most posts on here about how to change a friggin' light bulb, or which bulb gives off the whitest light, etc (which, BTW, is NOT good for driving, but hey, it looks cool). And it sounds like he has researched his idea pretty good.

Nissan engineers may have put our stock snorkels in just for the sake of getting cooler air. Most manufacturers do this. So in effect, we may all ready have a CAI.

That said, isn't there a high pressure area at the base of the windshield? Anyone thought/tried fabricating an intake opening there, much like the old Trans Am's? Just an idea; might not need as many or as sharp of bends (it may be able to be a gentler angle). Might get tricky with limited room, though.

Spaniard, as for looks, couldn't you place the "scoop" part in the very bottom center grill area (below front plate if you have one), and run the tube off of one side of it? This would keep it pretty hidden, protect it from bottoming, and may work just as good. Not saying it looks bad, but I don't believe in "advertising", and it would stop a lot of people asking dumb questions.

Dave
Old 03-18-2004 | 10:45 AM
  #57  
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Originally Posted by Dave Holmes
That said, isn't there a high pressure area at the base of the windshield? Anyone thought/tried fabricating an intake opening there, much like the old Trans Am's? Just an idea; might not need as many or as sharp of bends (it may be able to be a gentler angle). Might get tricky with limited room, though.

Spaniard, as for looks, couldn't you place the "scoop" part in the very bottom center grill area (below front plate if you have one), and run the tube off of one side of it? This would keep it pretty hidden, protect it from bottoming, and may work just as good. Not saying it looks bad, but I don't believe in "advertising", and it would stop a lot of people asking dumb questions.

Dave
Thanks for the ideas and comments, Dave. I like the idea of a duct going down around the base of the windshield... Only problem is it would take some major custom fabrication and also have little room to work in as you said. Also the Cubic Feet per Minute might not be enough to match/ replace the larger assembly that I have running below. If I was to try to add it to the existing system, running them together at some point can have a couple drawbacks it seems to me. 1)turbulence and 2) if 1 channel has significantly more pressure (e.g. windshield) than the other then the lower velocity/pressure pathway will get counter-acted by the higher pressure one. So I figure on checking if the one I got does anything measureable before tweaking it again. (though I did wrap the entire assembly with insulating foam- including midpipe as I found that it gets hot..)

As for why I didnt try to work it from the bottom grill (It would look lots better, I totally agree) - There is very little room to work with and the air would have to make even more twists to get around to the engine bay. Also I would be taking away from some of the cooling that the radiator would get. (e.g. track days) and I wouldnt want to overheat the engine (as that could lead to both mechanical issues, and overly hot engines generate...if im not mistaken... less power [Must have...more powaaaaaaaaaa])
Actually, in the previous version, I tried getting some airflow hook-up from the grill area. (actually there was alot of tubes running around

It was a pain trying to get the air around the frame. Check out the pix.


You can see how restrictive the front area is- the red hose is as large as possible for making it out and around to where it can go up to the engine bay. It was about 1.75 inches in diameter. Im pround to say I got 4" pvc going x2


I should have some good experimental data on this stuff in the next couple weeks. Ill set up my camcorder to record what the manometer does at various gear/throttle/speed combinations. Should be interesting I hope. If I make it to a 1/4 event with time to spare I also might consider opening the air box for a run or two.
Old 03-18-2004 | 05:29 PM
  #58  
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Originally Posted by Spaniard
... I like the idea of a duct going down around the base of the windshield...
That is a good idea! I can't believe I didn't think of that back on post 28. D'oh.

So are you going to blow off the manometer bit? Wouldn't blame you. Oh well, like I said before, I like your work. It beats the hell out of CF decals.
Old 03-18-2004 | 07:36 PM
  #59  
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Originally Posted by bluemaxx
That is a good idea! I can't believe I didn't think of that back on post 28. D'oh.

So are you going to blow off the manometer bit? Wouldn't blame you. Oh well, like I said before, I like your work. It beats the hell out of CF decals.
Thanks Bluemaxx- No I am curious to do the manometer! I like your idea. It will give some metrics to possibly start answering / understanding this stuff better. I'll even post the videos of the manometer readings in different scenarios- assuming it does more than just sit there at zero
Old 03-18-2004 | 10:54 PM
  #60  
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you. have. got. to. be. kidding. me.


you know what the average temp of air is at 1 foot off the ground on a typical summers day in Santa Cruz, CA? Say... it's 90* outside. Come... 12 noon, the temp 1 foot off of some asphalt should be right around.... oh.... 130*. If anything, you've increased the drag coefficient of your vehicle by a few tenths of a point. gg
Old 03-18-2004 | 11:10 PM
  #61  
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Originally Posted by antonthegrey
you. have. got. to. be. kidding. me.


you know what the average temp of air is at 1 foot off the ground on a typical summers day in Santa Cruz, CA? Say... it's 90* outside. Come... 12 noon, the temp 1 foot off of some asphalt should be right around.... oh.... 130*. If anything, you've increased the drag coefficient of your vehicle by a few tenths of a point. gg
You do the best you can with what cha got to work with... Its not as bad as you say tho. Remember on roads, theres CARS zipping alot and moving the air around so that the air doesnt just sit there and heat up 40 degrees above ambient temp. Besides, Santa Cruz doesnt get into the nineties.. more like 70s in the summer cause of the fog
And drag coefficient doesnt impact acceleration that much below say 90 mph I would guess? Maybe mileage somewhat.

AND I would take air from 1 foot off the ground that is completely external to the engine bay over air coming from what, 2 feet off the ground? that travelled into into the engine bay? and travels through a smallish uninsulated metal tube that is maybe 200 degrees? for maybe 3 feet?
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