6G Celicas Forums

Alright guys. I've been looking into intake induction for a while now. I've probably changed out my intake design probably 5 times already just to try to get better gains. I was thinking about getting cold-air intake next since I have a short-ram intake. BUT, as I was thinking, something hit me and it got me questioning really good. As people keep talking about intake, they talk about airflow and how it gives more horsepower by more airflow into the chamber. And ofcourse, more air means more fuel needed. But something else hit me hard. I've changed my intake system a couple times already and all of them felt different in responce. Not majorly but you can tell (it's ur car, you would know). Intake isn't about how much air is going in. Now that I think of it, it's about vacuum! It's not air getting pushed in, it's air getting pulled in. So I questioned to myself, how do I increase the vacuum velocity so that I can get some better gain than what I have now. Well I did some quick research. Apparently, it's all physics. Something that I'm not good at. But my uncle majored in Quantum Physics in college. So I asked him, "Hey, do you know anything about vacuum and velocity for airflow?" And he said, "Yeah. What for?" I said, "I'm trying to figure out how to make air sucked in faster into the my engine without having to spend a big butchet." And he said, "The smaller the pipe, the more vacuum you'll create." And I paused. I said to myself, wait a minute, most of the time, bigger is better when it comes to cars. Like for instance, the bigger the tubing, the more space it would have to channel air to be vacuumed. But it would not create faster vacuum or would it? Not sure but I decided to do more research. And it turns out, that constriction (snake swirl) type tubing actually helps vacuum velocity increase. Not only that but if you have a constriction figure at the both ends or in the middle of a tube, velocity speed increases and also less pressure. I'm stealing these methods from G. B. Venturi who died 1822 as a Italian physicist. http://biyografi.info/kelime/venturi So I figured, how come no ones ever really thought about this? This would actually evolutionize intake tubing design. What do you guys think? Am I onto something?

This post has been edited by FortuneCookie: Aug 15, 2007 - 10:35 AM

tornado, the $60 "turbo" is what you basically came up with. It sticks into your intake tube and swirls the air around. Creating more velocity.

The truth really is that even if you have uber velocity, your intake manifold will most likely not notice the difference. you did good with your howmework tho and i like your thinking. I think if your gonna do this velocity testing and stuff you should have a dyno to back your results up. No intake variation will give you much noticable difference while your driving. But if you could get some dyno numbers in there many more people will accept your ideas!

more restriction will create more vacuum, but that doesn't mean you will make more power.
the idea behind a cold or short ram intake, is to allow for more airflow, with less restriction, then the factory air box provides.

This post has been edited by lagos: Aug 15, 2007 - 10:26 AM

because how much air an engine can ingest isn't determined by its intake.
Well it is, like if you had no air at all then an engine wont run, but adding restrictions to gain velocity isn't going to do any good.

velocity of air and how much air is in that velocity is what is key.
of course I can push more air at a higher velocity out of a straw than a 4 inch pipe. Guaranteed the larger 4 inch pipe flows more air though, just at a lower velocity.

besides once that air is past the intake an in the manifold it doesn't matter how much velocity you think your adding because the air just slams into the valves that ultimately determine how much you ingest.

Just stick to getting the most cold air into the intake with the least restrictions possible.

I'm not a physics major, this is just what ive come up with. Just my .02

True. I was thinking about doing dyno tests too. But first things first, I'm definately starting this project just to make sure. But the tornado, no. LoL. That thing isn't what I had in mind. Becuz the fact that it has a star like figurine throughout the whole diameter of the pipe, it'll actually slow down vacuum. But I'll figure it out sooner or later. Right now I'm most likely gonna save up some money to create my own intake designs and different variations and then dyno testing them. Thanks for the comment bro.

I like that straw analogy. Think of it the other way around. Your the engine. Which can you suck in more air with, a straw, or bigger pipe?

That's what I was asking myself. So I'mma make different size pipes and see which one dyno's better.

It will be interesting to hear the results...

This post has been edited by ecaddiction: Aug 15, 2007 - 10:43 AM

In venturi shape pipe, air moves faster through the smaller section and pressure drops (vacuum gains) in order to maintain its energy (Bernoulli's theorem of conservation of energy) However, flow rate will remain constant due to change in cross sectional area. It is true that when you reduce the intake diameter, air will move faster through it. However, you will never surpass amount of vacuum causing by pistons moving down. If your intake is smaller than the TB, you are creating restriction, period.

Try squeezing your nose and tell me if your can breath better.
Or look at this way, after running, you are tired and need more air, you start breathing through your mouth. Why?
You need more oxygen going in and you are getting rid of CO2.
Both at a higher (flow) rate than usual.
Your nose is too restrictive for large amount of air being sucked/pushed to/from your lungs.

Larger = less restrictive
For the intake pipe before TB, larger is ALWAYS better.

Nice nice. So ofcourse, vacuum will be much faster with a smaller diameter piping, but only through the piping area as so it seems. So bigger is better on the diameter. But what about the constrictive (snake swirl aka helix) design? Supposably that will cause vacuum to increase as well. Maybe not much gains but definately should improve engine responce. I wanna make sure that what I'm testing will be worth testing becuz I've already researched and it'll probably be about a $300-$400 experiment.

You know what guys. I did more research, turns out that someone's already done the intake design. AIRMAX made a spiral intake design already in which I was going for. I'm not sure what the gains are but I'll definately check it out but the only problem is that it costs $300. So I'm just gonna drop the experiment.



Thanks for the help guys.

This post has been edited by FortuneCookie: Aug 15, 2007 - 12:11 PM

thats cool lol

watever, intake doesnt even give you that much gain...

its actually the opposite. vacuum is the absence of pressure. the lack of air and pressure in the combustion chamber, during the intake stroke, creates a pressure gradiant that allows atmospheric pressure to force air into the intake system. what you want is the least restrictive intake possible. this will allow the natural air pressure to push the max volume of air into the intake. making more power isnt so much about air speed as it is about the density of the air you have to burn with the proper amount of fuel.

think about ACIS (acoustic induction control)
the 3 stage ACIS on my v6 is a system that varies the length of the intake manifold depending on RPM. From what I gathered, a long intake runner is good for low end and a short intake runner is good for high end.

I wish I understood this concept a little better but it gives you something to look into.

It wont do anything for you..It will probaly creat more turbulence that it would help.Because its just hiting a wall of valves. Plus ive dont someing similar when i played paint ball.The ventury bolt actually slowed my velocity.I measured with a Chrono.And was running three rugulators on a N2o tank so there where no veliity spikes.

x2

you can try all sorts of sizes for piping and types of air filters to reduce restriction and improve airflow but in the end, it won't make any major increase in power...
since the intake stroke can only suck in a certain volume of air, you're better off researching ways to increase oxygen gas (O2) per unit volume (ie turbo or supercharger). just my 2 cents...

agreed. there is a limit to how much oxygen is being taken in at the stroke. increased velocity will not change the volume of air that the engine can use.

agreed. its still being pushed in by atmospheric pressure (1 bar...14.7psi)

but what your uncle said about smaller makes more vacuum velocity is true. this what the T-VIS system on first and 2nd gen 3s-ge and 3s-gte's did...closed of half of the intake runner at the side of the head so it had to suck throw a smaller hole at lower rpm under 4000-4200rpm for better torque and response then after it opened the other half! but on the 3s-gt3 open at 4000rpm was a bit late cause the factory turbo was well on full boost by then so most 3s-gte moders get them gutted (the buttiflies in the plate pissed off)...

but yeah for the sack of max power and top rpm bigger is still best!

Everything depends on your head design and your intake and exhaust runners. If you have long small intake manifold runners and small ports in the head, intake and exhaust and a long small tube header then you will have low end torque but no high end power because the engine runs out of air volume because of the small ports and tubes. If you have a short large intake tubes (ITB's and velocity stacks) and large ports (port and polish anyone?) and short large tube header (zoomies?) then you will have high end power but no low end torque (this is because there is no velocity in the air but volume). Toyota designed these engines to have a close happy medium with fuel efficiency thrown in. So just changing your intake and filter will only help remove restriction and gain you more top end (volume). If you want to gain more then port and polish your head, I recommend a professional for this, and change your intake manifold and exhaust header. If you want more low end torque then change your head for one with a smaller ports (not feasible for most engines) and change your intake and exhaust manifold to match. As stated before some engines were set up to adjust the intake runner to partially gain low end or high end but not much. As some people do they make a hybrid 7AGE with the 4AGE head because of the difference in design, but some of the heads were designed for volume/flow (large port) and some were designed for torque (small port).

im gonna steal ur idea and make millions lol