Intake Manifold - Explained

hello everyone and welcome to this

week's video today I'm going to be

explaining intake manifolds and

performance intake manifolds now this

intake manifold here is a skunk to

intake manifold for a cure Integra's

courtesy of redline 360 comm so I will

include a product link in the

description that you can go ahead and

check out but basically intake manifolds

are a pretty essential part of the

engine they're basically the last step

before the air goes into the engine nine

goes into the cylinder head so what

we've got going on is looking at an

intake manifold you've got your air

intake your throttle body and your

intake manifold so the air goes into the

air intake travels through your throttle

body into your intake manifold and from

there into your engine through the

cylinder head so this is just kind of a

top down look on the intake manifold so

ideally with your intake system you want

all the components to have the same

diameter so your air intake your

throttle body and your intake manifold

shall match up so the air can flow very

freely throughout now one thing that you

can do with the intake manifold is kind

of port match it to the throttle body so

you can grind away material here where

the air first enters the intake manifold

and have that match up to the throttle

body so that you have a very smooth

transition into the intake manifold now

as you can see there's all kinds of

connections all over this intake

manifold as it's a it's got a lot going

on and it's kind of an essential thing

that seems very simple but quite a few

things connect to it and use it as a

resource so let's go ahead and look at

my engine and talk about these different

connections here so looking in the

engine bay we can start with the air

filter work our way to the throttle body

and then connect it to the throttle body

we have the intake manifold

so just for comparative purposes I've

got this gunk to intake manifold sitting

here right beside it so there's quite a

few connections you can see that the

intake manifold kind of plays an

integral role in the engine as far as

all kinds of different sensors and

things going on so let's kind of look at

them one by one and talk about what

we've got so the first and kind of most

obvious connection is the throttle body

so the throttle body is going to melt on

the left side of the intake manifold and

that would

be mounting to like right here on this

face right there and that of course

controls the amount of airflow that the

engine gets when you open that valve

inside of there kind of the next most

important thing is going to be the fuel

rail obviously you need fuel in order

for this engine to do anything so that's

going to be this rail right here and

then each of the injectors is going to

be right in there and so you can see the

little holes in this intake manifold

where each of your injectors are going

to be spraying fuel that's what this

little notch right here is out for

that's where the fuels can be spraying

in now behind the intake manifold you

can see here kind of connecting between

the throttle body and the intake

manifold is the idle air control valve

where ia see valve and what this does is

when your throttle is closed when your

throttle valve is closed this can

regulate and allow for more air to go

inside an intake manifold and what that

does is it allows the ECU to manage the

idle Rev the Rev limits basically what

our PM you're going to be spinning at

when you're just idling and that

throttle is closed so looking at the

scum to manifold you can see little

passageway for the IHC valve and that's

where that air is going to bypass in

order to go into the engine with the

throttle body closed now right in front

of the plenum you can see the mount here

and this is just so you can adjust your

throttle cable and keep that taut so

here is where that would be mounted and

you can adjust your throttle cable with

that mounted on top of the intake

manifold we have the evap purge valve

which is basically part of the

evaporative emissions system and what it

does is it allows for evaporated fuel

from the gas tank that's expanded in the

gas tank to be burned off in the engine

now mounted on the top of the intake

manifold you can see this hose

connecting to the valve cover and that's

a breather hose and basically what that

is is it's part of the positive

crankcase ventilation system and it

allows for airflow from the intake

manifold into

the valve cover it actually does travel

in this direction another one of our

many sensors in here this sensor right

here this is the IAT sensor or the

intake air temperature sensor and

basically what this does is it monitors

the air temperature and gives that

feedback to the ECU which will then

change the air fuel ratio accordingly so

if it's a warmer air temperature it will

inject less fuel and if it's a cooler

air temperature meaning more dense more

oxygen than it can inject more fuel and

so here on the sky too you can see where

you would mount the IAT sensor and

finally one of the last things to check

out is this vacuum line here in the back

of the intake manifold and if you follow

this hose you can see that this runs to

the brake booster so that provides the

vacuum for your brake booster for your

power brakes so that's kind of a general

look at the intake manifold yeah as you

can see it's kind of a complex thing

that looks pretty simple but it has

quite a few connections and all kinds of

different tools and sensors in it that

are mounted to it and rely on it

function so finally let's talk about

what makes a performance intake manifold

so basically you just want to increase

the size of the intake manifold of the

plenum and the runners so that you can

have more air flowing through it and the

other thing you want to do is remove any

curves or obstacles that may exist

within it so the air can be free-flowing

throughout the entire intake manifold so

this particular scum to intake manifold

features a 70 millimeter opening and it

has oversized runners and a larger

plenum to allow for more airflow and

also these ports here kind of match to

the cylinder head so that kind of lines

up really well and it also minimizes

curves you can see it's fairly straight

design very simplistic and that's a good

thing here so don't forget to check out

redline 360 comm in the description and

if you have any questions or comments

feel free to leave them below