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The Young One
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This is a very interesting thread. I have saw people put this on their cars like on hondas and I think a air filter like a k and n can fit in the hole. Would this work as a ram air? I guess it is called a velocity stack.
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BLUE 3"UNIVERSAL Aluminum Turbo Intake/Short RAM Super Velocity Stackw/silicone
 

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Just Some Dude in Jersey
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Discussion Starter · #43 ·
The whole point of this thread showed that rammed air doesn't really work until you are going over 100mph. As GGL said in post #18: "If it was that simple you would see it on just about (every) car you can imagine."

That's an important point to keep in mind about the various gadgets you see offered. EVERY car maker wants to boost their cars' power as high as affordably and reliably possible. If a $1 plastic funnel would make any appreciable increase in power, then all cars would have them. Same with rams and scoops. Don't forget that after most rams and scoops there is an air filter, plus all sorts of twists and turns to the air intake, and then the biggest blocker of air flow: The throttle plates themselves. At most driving speeds your throttle is barely open, like maybe 25% open while CRUISING at 80mph. When you floor it and open the throttle the remaining 75%, you only go a little bit faster.

Also keep in mind that air goes into your engine primarily because of SUCTION from the piston intake downstroke. You need to blow a heck of a lot of air at really high pressure to increase by just a few percent how much air actually goes into your engine.
 

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Did someone say Leaf blower turbo? - The Roadkill Monza is Back, and it's Bringing the Boost Caboose!

The Boost Caboose on Roadkill!
You can watch the episode on Motortrend on demand streaming service. And while you're there watch Engine Masters, they have a lot of episodes testing turbos/superchargers on the dyno and a ton of information.

(I'm not a salesman for Motortrend)
 

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Detritus Maximus
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This is a very interesting thread. I have saw people put this on their cars like on hondas and I think a air filter like a k and n can fit in the hole. Would this work as a ram air? I guess it is called a velocity stack.
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View attachment 441189
BLUE 3UNIVERSAL Aluminum Turbo Intake/Short RAM Super Velocity Stackw/silicone

Sam-

(Everyone feel free to correct anything from this point on...)

One thing to understand about these things is that many of them are attempts at correcting losses not actually gaining anything. Air is a gas, gasses move like fluids...so it's easier to visualise how water acts (since we can see water!), or better yet, how large crowds of people move when exiting a sports arena.... Ever notice how some toilets have a nice smooth flow when you flush and others are very turbulent? Air moving into and thru an intake tract is much the same. The carb can only flow a maximum amount of air at wide open throttle no matter how good the rest of the intake tract is, both before and after the carb.. But intake tracts are full of bad things, like sharp edges, right angle turns, ridges, accordian textures, drain tubes, under hood heat and all sorts of things. All of those things conspire to slow down the air flow thru friction and turbulence (this where the exiting crowd analogy comes in handy). There is a thing called a boundary layer where air along a surface (like inside the intake duct) slows down due to the friction against the duct wall, yet the air in the middle of the still flows faster. The crowd in the center of the exit corridor moves faster than the people along the walls and the people lined up with the door way go thru while those on the sides bunch up and have to squeeze thru, slowing everyone down. Watching a river flow shows the same thing. faster moving water further away from the bank and slower water along the edges and even areas where the water is still.

Anyway, the velocity stacks/ram tubes don't gain anything, just correct an inefficiency. Ram Air is usually not really ram air, but more often than not an attempt to either reduce losses in air velocity at higher rpm due to convoluted intake ducts or to get cooler air from outside the engine bay as cooler air is more dense therefore more oxygen molecules to burn, but under hood air can get pretty hot, which does two things, it gets less dense (fewer oxygen molecules to burn) and the hotter air has less of a cooling affect on the carb and intake.

Here is the Weber DGAS version of a velocity stack:


Low Profile Velocity Stack (Air Horn) for Weber DGV or DGAS - Pegasus Auto Racing Supplies


Rectangle Font Musical instrument accessory Bicycle part Auto part



On a naturally aspirated motor it's all about reducing losses due to most parts not being perfect or optimum. You might be increasing hp/torque over the factory rating, but that rating is still based on loss in potential acceptable to the engineers and the accountants. In engine rebuilding that is what 'blueprinting' is all about since few motors come out of the factory perfectly built.

The only ways to really 'gain' over the designed in potential of a motor is with turbos, superchargers, nitrous. Or run 200 mph at Bonneville

Or all three...like this:

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Detritus Maximus
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A little follow up...I was looking for video of the Dobbertin J2000 actually running. Instead I found an article about it and apparently when trying to decide what car to use as a base, the Chevy Chevette and the Opel GT were considered.
Also, that crazy motor is running a carb, not fuel injection....

I have decided not to post more pics of the engine as it may have an inspirational effect on Gordon. I don't want to be responsible for him O.C.'ing...'over chroming'.
 
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