HKS Intake duct.

[KKaWing]

Originally Posted by sierra

Drrrrr! Now I am embarrassed. Especially when geography was one of my better subjects. I'll correct that.

Well maps/locations of places is not the only aspect of geography... how humans interact with the world spatially is another. Tourism, environmental conservation, and spatial analysis are amongst some. You'll even meet geographers that don't know the atlas off by heart!

[B L U E S L A T E]

Anyone in the SoCal wanna start a group buy on this?

[FR-Sizzle]

Originally Posted by Admiral Ballsy

If - IF - there is anything to be gained from pressurization (and I'm pretty confident in this case there isn't), it's got to be, well, pressurized. Which means no drain holes, etc.

When your driving at 60-80 mph I doubt the 3 holes would make a big difference if any. Air will be entering so fast when your driving at that speed and dont forget that air is also getting sucked into the air box, so the holes wouldnt make that big of a difference if any. They are so small that they probably wouldnt effect the performance of the part at all. If you are paranoid about the holes hurting performance it shouldnt be that hard to cover up... get some super glue and put a piece of plastic over the holes

Its like how that sierra poster thinks the Max Racing duct would effect cooling of the radiator just because it is covering the radiator a little bit when in reality when your driving around on the freeway or locally it has little to no effect.

[Admiral Ballsy]

Originally Posted by FR-Sizzle

When your driving at 60-80 mph I doubt the 3 holes would make a big difference if any.

Well, yes, they would make all the difference in whether there was any pressurization at all.

I've spent a LOT of time testing "ram air" systems (on motorcycles, FWIW), on a dyno, in a wind tunnel. My senior design project in college dealt with it - the Kawasaki ZX-11 had just been announced, the first bike (and AFAIK the first road vehicle, period) with a true sealed and pressurized intake tract.

You don't get any benefits AT ALL unless the system is 100% sealed, and you have to be traveling over about 100MPH. Even then, the difference is quite subtle - it's less a power boost than it is a 'reshaping' of the power curve.

"Ram air" systems on cars nearly always derive whatever benefits they provide through cooler air, not pressurization - if for no other reason than street cars almost never go fast enough to gain anything.

[zooki]

Originally Posted by Admiral Ballsy

Well, yes, they would make all the difference in whether there was any pressurization at all.

I've spent a LOT of time testing "ram air" systems (on motorcycles, FWIW), on a dyno, in a wind tunnel. My senior design project in college dealt with it - the Kawasaki ZX-11 had just been announced, the first bike (and AFAIK the first road vehicle, period) with a true sealed and pressurized intake tract.

Please don't bring any real world experience into this conversation. It tends to contradict some people's preconceived notions & expectations. Thanks.

[Anaxilus]

Originally Posted by Admiral Ballsy

Well, yes, they would make all the difference in whether there was any pressurization at all.

I've spent a LOT of time testing "ram air" systems (on motorcycles, FWIW), on a dyno, in a wind tunnel. My senior design project in college dealt with it - the Kawasaki ZX-11 had just been announced, the first bike (and AFAIK the first road vehicle, period) with a true sealed and pressurized intake tract.

You don't get any benefits AT ALL unless the system is 100% sealed, and you have to be traveling over about 100MPH. Even then, the difference is quite subtle - it's less a power boost than it is a 'reshaping' of the power curve.

"Ram air" systems on cars nearly always derive whatever benefits they provide through cooler air, not pressurization - if for no other reason than street cars almost never go fast enough to gain anything.

Wasn't going to bother asking but since you have some actual experience, might as well. I've also spent some time w/ a flow bench working on heads and intakes. The question being, do you think the the 10x increase in intake volume could hurt low end throttle response by reducing port velocity? It's also got that kink which doesn't help.

[Admiral Ballsy]

I'm not sure exactly what you're asking - by 'intake', do you mean the air tube? In my lexicon (yes, I'm old), 'intake' means 'intake manifold'.

The only thing in front of the throttle body that would affect velocity would be the relative air pressure. Volume isn't changing; the combination of TB flow characteristics and pressure are going to determine velocity, all else equal.

[zooki]

I think you port velocity will be affected more by the plenum size of the actual intake manifold, and the shape & length of the runners, not the air filter assembly. Unless you change the actual intake manifold I can't see it making much of a difference. IMHO, 5 HP @ 7000 rpm isn't going to be noticeable in a 2800 lb. car. But that's just my opinion.

[Admiral Ballsy]

Originally Posted by zooki

I think you port velocity will be affected more by the plenum size of the actual intake manifold, and the shape & length of the runners, not the air filter assembly. Unless you change the actual intake manifold I can't see it making much of a difference. IMHO, 5 HP @ 7000 rpm isn't going to be noticeable in a 2800 lb. car. But that's just my opinion.

I agree 100%.

[Anaxilus]

No, not the manifold, obviously the intake 'duct' in question here. Everything in the chain affects the system. The reason I ask is because you can increase volume and cause reduced velocity which leads to loss of low-end responsiveness for high-end gain. Not dissimilar to dropping an oversized carb on a big block. You get big numbers but terrible throttle. It's not just a matter of volume being pressurized, this why venturis are employed, to increase speed. If you mean you don't think it will matter much because the butterfly and everything after it is the same, then I get your meaning.
_____

Response isn't measured by horsepower in the upper range. Are you saying all variations of air filter box design apart from OE are snake oil? The media is not the only restriction in the chain.

Anyway, I guess I'd like to see the flowbench numbers on this product, if there are any.

[Admiral Ballsy]

Originally Posted by Anaxilus

Everything in the chain affects the system.

Not in both directions. Sure, you can restrict flow upstream of the TB, but you can't increase it beyond the native characteristics of the TB itself. You're not going to get any more air into the system that you'll get with nothing in front of TB at all.

Venturies affect speed, but not flow. It's like electricity - you can increase voltage, you can increase current, but you can't do both at the same time; power out can't exceed power in.

[Anaxilus]

Originally Posted by Admiral Ballsy

Not in both directions. Sure, you can restrict flow upstream of the TB, but you can't increase it beyond the native characteristics of the TB itself. You're not going to get any more air into the system that you'll get with nothing in front of TB at all.

Venturies affect speed, but not flow. It's like electricity - you can increase voltage, you can increase current, but you can't do both at the same time; power out can't exceed power in.

Right, which is why I was wondering if this duct could potentially reduce speed by increasing volume. As you put it, it's like Ohms law, so you are playing a zero sum game in your analogy.

[zooki]

Come on, you know we go by how "cool" parts look and "butt dynos" on this forum. We have no room for empirical data....
I do know that years ago I measured just how much "ram air" effect a scoop placed directly in the front of a car(under the leading edge of the front bumper). It came to 4 inches/water at 100 MPH. Which is about 1/7th of a pound, give or take.

[sierra]

Originally Posted by zooki

Come on, you know we go by how "cool" parts look and "butt dynos" on this forum. We have no room for empirical data....
I do know that years ago I measured just how much "ram air" effect a scoop placed directly in the front of a car(under the leading edge of the front bumper). It came to 4 inches/water at 100 MPH. Which is about 1/7th of a pound, give or take.

So the ram effect is negligible. What is important is cool, stable air without restriction to the throttle body requirements. This intake looks able to deliver that[for its part] whereas an intake placed directly into the incoming air is in danger of an erratic supply from turbulence, unless it's placed in clear air as in F1 cars.