Supermachoman

I know the JWT and Stillen short ram intakes come with them. I know they are supposed to suck air in faster (thus more), but how well do they work? Since the JWT intake is only ~120 I figured I might try adding the velocity stack to my PR CAI. I know the gains will be ~0, but I just like to experiment. Any thoughts?

theblue

very simple... your filter is larger than the hole the air must go through. Right now you just have flat plastic and a smaller hole at the back your filter (not very good for flow) you are effectivly replacing that sheet of plastic with a hole with a polished metal cone allowing much better flow. I have had both types of filter and I do believe it helps (maybe only 1-2 HP) you won't feel anything, but every HP helps.

Supermachoman

That's what I thought. Thanks's for clearing it up Aaron. BTW do you happen to know if we can buy the velocity stack by itself? Or would it make more sense just buying the JWT intake (since I'd need a different filter that would have to fit over the outside of the velocity stack)?

xHypex

iTrader: (1)

You can probably buy the velocity stack by itself, but I doubt it would be much cheaper than the combo. Loren put the velocity stack on his CAI for his supercharger and noticed a considerable gain. That should mean that even a NA car should gain something.
-hype

Nismo

iTrader: (18)

how are you going to attach the Velocity stack onto the CAI? are you using the hybrid setup? I dont see how it will connect to the lower pipe.

SuDZ

Dumb question maybe but what is a velocity stack?

SuDZ

RedMax95

that would be cool but i think it would get the lower pipe out of place, but if you were to put it on before the cai is drilled than that would work, of course with the sc he prob. had to make his own hole anyway

Burton069

iTrader: (2)

love the sig

got rice?

iTrader: (2)

straightens the airflow, creating a higher airflow into the intake manifold. There's also an expansion area after the velocity stack, which creates a low pressure area.

2K2DEMAX

iTrader: (1)

I did this with mine a couple of months ago and actually felt a difference down low - mid range (moving from a standstill). I couldn't feel a difference at the top and I never dynoed, so who knows. The downside is that I had to take it off because the diameter of the top of the filter was too large. It caused it (the guard) to protrude enough to rub against the tire during right turns.

Now I don't know if there is more room for the 4th gens but for me (5th gen) the room was insufficient. BTW, for the "how do you bolt it on?" I got an intake adapter, some hose and a clamp.

NismoAce

iTrader: (6)

someone should look into making just the stack or a combo stack with short ram piping or cold air piping. I bet they would make killer bucks.

MadMax07SL

Someone should stop bringing back to life 8 YO threads...

MaxiNone

iTrader: (1)

damn, 120 for that. doesnt auto zone sell those things for like 25?...

NmexMAX

iTrader: (22)

http://www.bpinitiatives.com/stacks.php

G4nismo

iTrader: (9)

what are these vel stack contraptions?

floppynuts3333

Seen a lot of different dynos with a significant loss down low...only a few cases of gaining 1-2hp way up high...air is compressible and acts different than water being pushed through a "nozzle", and below the speed of sound you cannot get the desired effects of changing pressure and velocity of airflow to work for your car without a change in motive force. I would't get one....if you get one of these you might as well pick up a "tornado". J/k. I'd like to hear of any maximas running with one.

NmexMAX

iTrader: (22)

I gained a lot with just the intake from JWT, all around/total area which, incidentally has this velocity stack.

shrek

i felt a difference to in my single cam KA24 powered s13 ...but maybe my butt dyno needs some calibration hehehehe.....by the way I think the OP doesnt even remember about this thread

Leo_Koneval

iTrader: (4)

I am not sure exactly how velocity stacks work on a technical engineering level but I think its a placebo.

For example if you were to open your mouth wide and then breath in, it would be easy and you fill your lungs fast and quick. But if you were to take a deep breath with only your nose it takes longer and you need to breath in harder to get that same amount of air.

That is my take on this velocity stack, sucking air through a smaller opening might get the air moving faster and with more force but you are also taking in less air.

aackshun

iTrader: (3)

You just supported buying a velocity stack and you didn't know it...

Lips -> Throat -> Lungs

Throat = Velocity stack, since it's SMALLER than the opening in your mouth.

Filter -> Stack -> IM

Works kinda the same lol.

Unless someone wants to run a test... 3"->6" Filter w/ no stack and 3"->6" with a stack, I'm gonna be on the GET A VELO STACK side of the arguement.

Leo_Koneval

iTrader: (4)

So....................................... if you were to have a allergy to a bee sting and your throat swelled up. You are saying that you will be able to get more air which will increase your horsepower?

What I was thinking of it as is this:

Stack -> Intake pipes -> Intake Manifold
Nose (Which represents the stack) -> Throat -> Lungs
Mouth (Which is no stack) -> Throat -> Lungs

Overall, you are only going to be able to push as much air as a 3in TB, 3in intake pipe, and 3in filter is going to allow you to. And lets say that the MOST air you can fit into the entire intake system is something like 10 liters of air, unless there is some magical force of nature pushing and pulling that air into that sexy hole and out another still sexy hole I don't think its going to bend the laws of capacity. Unless that force is a turbo or supercharger which pushes the air molecules together.

I think at best the velocity stack is probably going to help fill voids in acceleration where there might be a little delay in the time air takes to come into the intake. Like you go from idle to WOT immediately in one go.

I think its counter intuitive like we try to get the biggest filters and exhaust we can eliminate back pressure so its easy in and easy out. But if we put a restriction there, isn't that going backwards? But either way there is only one way to prove this.............. TO THE DYNO!

Sorry for writing so much.......

cashoit

i think the real gains come from a more laminar flow provided by the stack. If it is located at the at the filter than it will make the incomin air less turbulent and flow faster. But read the info on the webpage. the stack is used for 6" filter to neck down to 3" and reduce turbulence.

Hell u couldnt even find a 6" reducer or i wd have gotten a 6" filter. Jus as an adapter for a 6" its good.

On a 3" filter if WD NOT be as advantagous. Might even choke off flow and cause more turbulence

cashoit

jus did a quick online search...

I cdnt even find a 6" inlet cone filter that necks down to 3" or a 3" to 6" reducer. U need a velocity stack to get down to 3". I dont think it speeds up velocity at all, i think its jus a coupling or reducer.

Leo_Koneval

iTrader: (4)

^^^^^^

YES! This man is a genious!

What you just said makes perfect sense, if you put like a 9 inch cone filter on a intake that is 3 inch in diameter you are doing nothing except take more space in your engine bay. I read somewhere that having too big a filter will give you negative effects... but ON TO GOOGLE!

Mr. Brett

iTrader: (7)

There. Using my wicked MSPaint skills, I've sketched up my conclusion as to how a VS functions. This is based off of some of the reading I've done. It keeps turbulent air from forming at the corners of the air filters in an attempt to keep the flow of air to the engine more smooth and constant.

On a NA application, I see potential for minimal gains unless you're putting it on a very powerful engine, such as an LS series.

For turbo and other FI applications, I can see a potential for good gains

Of course, some also mount V.S. on the outside of their intake (e.g. at the front bumper for a "ram air" kind of setup). I don't see this making any gains, as the turblence in the air filter would still be there.

hondakiller

Leo_Koneval

iTrader: (4)

I see what you mean now

Leo_Koneval

iTrader: (4)

SO........... that above image is one of the many reasons why aftermarket intakes are bad for our car not only are you losing power because of sucking in hot air from the engine bay but you are losing power for turbulence caused by the very filter you put on hoping to increase power.

And after spending $200 or some Injen intake you need to buy a $50 or whatever dollar velocity stack to correct the flaw in the intake design.

Unless you buy a $20 dollar intake like I did, which only means one thing... LEFT OVER MONEY FOR MORE THINGS!!!!!!!

Mr. Brett

iTrader: (7)

I mean, for our platform, as long as you're running NA, the difference between running a VS and not is probably not going to make a huge difference.

Hypothetically, yes, this thing should make more power. But for a NA 3.5L V6, I'd venture to say the gains are minimal, if any. For some people running high levels of boost, I would say this would be far more likely to net some good gains.

You'd probably feel more of a difference switching from the Injen "CAI" to a short ram setup than you would adding a VS to your intake for our cars.

BTW, velocity stacks can be had for pretty cheap. $25 for the Autozone special if I'm not mistaken. If you'd really risk putting "performance" parts from Autozone on your car.

It's finding a company that makes an air filter with a 6" inlet that's the difficult and costly part. I ended up dropping $48 on an AEM dryflow for my VS application for my Z. It was the only trustworthy, namebrand filter I could find readily online. And I didn't want to spend $150 on the APEX'i power intake.

NmexMAX

iTrader: (22)

And we come to my whole "shape of the curve" theory, vs peak values. When using a VS, the shape of my power curve was quite linear and smooth, when using no velocity stack (both w/ an after market cone & stock airbox) the curve showed a little bit of 'choppiness' etc.

Air is a liquid, or at least it behaves like one.


But, SLC is right IMO, NA, probably not a huge concern, or even for the mild modder.

Leo_Koneval

iTrader: (4)

You guys are good haha.

Now that I think about it if the velocity stack was the same size at the intake opening as in, the opening in the VS was exactly the same diameter as the opening in the intake piping then that is where the good comes in.

But if it was smaller like the opening of the VS is 2 inch, while the intake piping and TB is 3 inches then that is where that restriction theory comes in that I had before.

Well now I understand hahah

cashoit

Well there is no point in using a velocity stack for a 3" inlet cone. But thats if u believe that u are somewhat starving the engine with the 3".

A 6" cone with VS would in no way starve the engine and response would be better. (THis is what i hrd from an orger that had the 6" VS setup). But the setup would cost likely 70 bucks for ehhh potentially better gains.