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Discussion Starter #1
This is how I break down most things car related because almost everything comes back to this principal (or you can bring it down to this level), from the fuel system, to the oil system, to the cooling system, to the intake and exhaust systems, to making power, and making things reliable, to aerodynamics/down force.

"Not everyone understands what a completely rational process this is, this maintenance of a motorcycle. They think it's some kind of a "knack" or some kind of "affinity for machines" in operation. They are right, but the knack is almost purely a process of reason [........] A motorcycle functions entirely in accordance with the laws of reason, and a study of the art of motorcycle maintenance is really a miniature study of the art of rationality itself,"
Robert Pirsig, Zen and the Art of Motorcycle Maintenance.

A motor or car as a whole is too complex to understand all at once. One of the biggest limitations of of the human condition is that we live in details but think in generalities. Embrace generalities and the issue of the whole becomes less of an obstacle. Yes, there is a philophy lesson in this too.

The basis of communication is language, written or spoken, because of that my favorite book ever is the dictionary. It is the key to the whole struggle of understanding and explaining. There is no better way to understand something than to be able to know the language used to describe it. Because of that I will quote definitions from the dictionary, a lot.

Main Entry: gen·er·al·i·za·tion
Pronunciation: \ˌjen-rə-lə-ˈzā-shən, ˌje-nə-\
Function: noun
Date: 1761
1 : the act or process of generalizing

Main Entry: 1gen·er·al
Pronunciation: \ˈjen-rəl, ˈje-nə-\
Function: adjective
Etymology: Middle English, from Anglo-French, from Latin generalis, from gener-, genus kind, class — more at kin
Date: 14th century
1 : involving, applicable to, or affecting the whole
2 : involving, relating to, or applicable to every member of a class, kind, or group <the general equation of a straight line>
3 : not confined by specialization or careful limitation
4 : belonging to the common nature of a group of like individuals : generic
5 a : applicable to or characteristic of the majority of individuals involved : prevalent b : concerned or dealing with universal rather than particular aspects
6 : relating to, determined by, or concerned with main elements rather than limited details <bearing a general resemblance to the original>

Main Entry: sys·tem
Pronunciation: \ˈsis-təm\
Function: noun
Etymology: Late Latin systemat-, systema, from Greek systēmat-, systēma, from synistanai to combine, from syn- + histanai to cause to stand — more at stand
Date: 1603
1 : a regularly interacting or interdependent group of items forming a unified whole <a number system>: as a (1) : a group of interacting bodies under the influence of related forces <a gravitational system> (2) : an assemblage of substances that is in or tends to equilibrium <a thermodynamic system> b (1) : a group of body organs that together perform one or more vital functions <the digestive system> (2) : the body considered as a functional unit c : a group of related natural objects or forces <a river system> d : a group of devices or artificial objects or an organization forming a network especially for distributing something or serving a common purpose <a telephone system> <a heating system> <a highway system> <a computer system> e : a major division of rocks usually larger than a series and including all formed during a period or era f : a form of social, economic, or political organization or practice <the capitalist system>
2 : an organized set of doctrines, ideas, or principles usually intended to explain the arrangement or working of a systematic whole <the Newtonian system of mechanics>
3 a : an organized or established procedure <the touch system of typing> b : a manner of classifying, symbolizing, or schematizing <a taxonomic system> <the decimal system>
4 : harmonious arrangement or pattern : order <bring system out of confusion — Ellen Glasgow>
5 : an organized society or social situation regarded as stultifying or oppressive : establishment 2 —usually used with the
synonyms see method



If you read and understand the definition of "system" you should be able to look at a car and define by systems the parts of the whole. You are generalizing the whole, based on systems, which is the rational way to examine the thing based on the human condition.

Oil system, turbo system, cooling system, intake system, exhaust system, sound system, timing chain system, etc etc etc etc. If you think you can explain to me a motor as a whole, I'll laugh, but if you can explain to me the systems as part of the whole, I'll listen.


Main Entry: ra·tio·nal·ize
Pronunciation: \ˈrash-nə-ˌlīz, ˈra-shə-nə-ˌlīz\
Function: verb
Inflected Form(s): ra·tio·nal·ized; ra·tio·nal·iz·ing
Date: 1803
transitive verb 1 : to bring into accord with reason or cause something to seem reasonable: as a : to substitute a natural for a supernatural explanation of <rationalize a myth> b : to attribute (one's actions) to rational and creditable motives without analysis of true and especially unconscious motives <rationalized his dislike of his brother> ; broadly : to create an excuse or more attractive explanation for <rationalize the problem>
2 : to free (a mathematical expression) from irrational parts <rationalize a denominator>
3 : to apply the principles of scientific management to (as an industry or its operations) for a desired result (as increased efficiency)

Rationalization can be either "making excuses", or "making sense" of.

This is the start of tying it all together.

Main Entry: 1pres·sure
Pronunciation: \ˈpre-shər\
Function: noun
Etymology: Middle English, from Anglo-French, from Late Latin pressura, from Latin, action of pressing, pressure, from pressus, past participle of premere
Date: 14th century
1 a : the burden of physical or mental distress b : the constraint of circumstance : the weight of social or economic imposition
2 : the application of force to something by something else in direct contact with it : compression
3 archaic : impression, stamp
4 a : the action of a force against an opposing force b : the force or thrust exerted over a surface divided by its area c : electromotive force
5 : the stress or urgency of matters demanding attention : exigency <people who work well under pressure>
6 : the force of selection that results from one or more agents and tends to reduce a population of organisms <population pressure> <predation pressure>
7 : the pressure exerted in every direction by the weight of the atmosphere
8 : a sensation aroused by moderate compression of a body part or surface

Pressure in any automotive system can be examined using pressure as a theme, but even within the confines of pressure there are several definitions. The greater your understanding of pressure, the more ways you can examine "pressure" and the relationships within the same system.

The main definitions of pressure to understand in relation to automotive systems are numbers 2, 4a and 4b, and 7. The most important are 2 and 7.

Why?

#2 in that is specifies a "direct connection", and #7 in that it mentions the atmosphere and the force it exerts in every direction, it ties in with #2 in that everything on this earth not in a vacuum is acted on my this pressure, which will lead into a few important things, which will be refined by definitions.

Main Entry: de·fine
Pronunciation: \di-ˈfīn\
Function: verb
Inflected Form(s): de·fined; de·fin·ing
Etymology: Middle English, from Latin definire, from de- + finire to limit, end, from finis boundary, end
Date: 14th century
transitive verb 1 a : to determine or identify the essential qualities or meaning of <whatever defines us as human> b : to discover and set forth the meaning of (as a word) c : to create on a computer <define a window> <define a procedure>
2 a : to fix or mark the limits of : demarcate <rigidly defined property lines> b : to make distinct, clear, or detailed especially in outline <the issues aren't too well defined>
3 : characterize, distinguish <you define yourself by the choices you make — Denison University Bulletin>

I'll leave off here for now, there will be a lot more to come. It'll be kinda round about meandering, but it will eventually tie together.

Main Entry: 2meander
Function: intransitive verb
Inflected Form(s): meandered; meander·ing\-d(ə-)riŋ\
Date: circa 1612
1 : to follow a winding or intricate course
2 : to wander aimlessly or casually without urgent destination : ramble
synonyms see wander


:thinking: :)
 

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:thinking: wtf...
 

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someone gots too.... but not me!!
 

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Discussion Starter #5
I could just draw a picture of how I think the PCV system should be but its more of a "give a man a fish, teach a man to fish" thing.

Are you a man or a fish? Do you like fish sticks? (southpark FTW)
 

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Discussion Starter #6
For flow to occur you need a pressure differential. Flow will occur from an area of high pressure to an area of low pressure, usually from one body or container to another via some passageway or orifice.

Main Entry: or·i·fice
Pronunciation: \ˈȯr-ə-fəs, ˈär-\
Function: noun
Etymology: Middle English, from Middle French & Late Latin; Middle French, from Late Latin orificium, from Latin or-, os mouth + facere to make, do — more at oral, do
Date: 15th century
: an opening (as a vent, mouth, or hole) through which something may pass
or·i·fi·cial \ˌȯr-ə-ˈfi-shəl, ˌär-\ adjective


Main Entry: 1body
Pronunciation: \ˈbä-dē\
Function: noun
Inflected Form(s): plural bod·ies
Etymology: Middle English, from Old English bodig; akin to Old High German boteh corpse
Date: before 12th century

3 a : a mass of matter distinct from other masses <a body of water> b : something that embodies or gives concrete reality to a thing; also : a sensible object in physical space c : aggregate, quantity <a body of evidence>


themain body most car stuff revolves around is the atmosphere. It sucks it in, does some stuff to it and spits it back out.
 

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dude to be honest i have no idea what this says... NO IDEA nota clue in the world! looks like something outa a science
book lmao
 

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Discussion Starter #8
dude to be honest i have no idea what this says... NO IDEA nota clue in the world! looks like something outa a science
book lmao
it's called a dictionary.......

Main Entry: dic·tio·nary
Pronunciation: \ˈdik-shə-ˌner-ē, -ˌne-rē\
Function: noun
Inflected Form(s): plural dic·tio·nar·ies
Etymology: Medieval Latin dictionarium, from Late Latin diction-, dictio word, from Latin, speaking
Date: 1526
1 : a reference source in print or electronic form containing words usually alphabetically arranged along with information about their forms, pronunciations, functions, etymologies, meanings, and syntactical and idiomatic uses
2 : a reference book listing alphabetically terms or names important to a particular subject or activity along with discussion of their meanings and applications
3 : a reference book giving for words of one language equivalents in another
4 : a computerized list (as of items of data or words) used for reference (as for information retrieval or word processing)


the cool thing is any of the words in there you don't understand you can look them up

http://www.merriam-webster.com/

one of the coolest things EVER
 

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For flow to occur you need a pressure differential. Flow will occur from an area of high pressure to an area of low pressure, usually from one body or container to another via some passageway or orifice.

.
At the bare minimum guys try to understand this, it's simple (well, simplified) and it's important for a lot of automotive stuff. Research 'flow', you'll learn a lot of interesting things
 

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Discussion Starter #11
At the bare minimum guys try to understand this, it's simple (well, simplified) and it's important for a lot of automotive stuff. Research 'flow', you'll learn a lot of interesting things
ding ding, it applies to everything automotive. The broader aspect of it is pressure differential. Differential even ties into aerodynamics, turbos, everything.

There are a few main points within flow and differential to "get" to, once someone wraps their head around those few basic concepts/parts, everything ties together.
 

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Discussion Starter #13
can i have the cliff notes please?
no, part of the point is learning to enjoy the process.


"Not everyone understands what a completely rational process this is, this maintenance of a motorcycle. They think it's some kind of a "knack" or some kind of "affinity for machines" in operation. They are right, but the knack is almost purely a process of reason [........] A motorcycle functions entirely in accordance with the laws of reason, and a study of the art of motorcycle maintenance is really a miniature study of the art of rationality itself,"
Robert Pirsig, Zen and the Art of Motorcycle Maintenance.
 

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Discussion Starter #16
so pressure differential and how it applies to the PCV system....

part of the definition of pressure

2 : the application of force to something by something else in direct contact with it

part of system

1 : a regularly interacting or interdependent group of items forming a unified whole <a number system>: as a (1) : a group of interacting bodies under the influence of related forces <a gravitational system> (2) : an assemblage of substances that is in or tends to equilibrium <a thermodynamic system>

orifice

: an opening (as a vent, mouth, or hole) through which something may pass

Main Entry: 1com·part·ment
Pronunciation: \kəm-ˈpärt-mənt\
Function: noun
Etymology: Middle French compartiment, from Italian compartimento, from compartire to mark out in parts, from Late Latin compartiri to share out, from Latin com- + partiri to share, from part-, pars part, share
Date: circa 1578
1 : a separate division or section
2 : one of the parts into which an enclosed space is divided

First things first, you have to figure out the compartments involved, where they connect via an orifice, and the relationship of each in terms of pressure.... remember, it's a dynamic system, so things aren't the same at every point in terms of where or how strong the differentials are.....

Main Entry: 1dy·nam·ic
Pronunciation: \dī-ˈna-mik\
Function: adjective
Etymology: French dynamique, from Greek dynamikos powerful, from dynamis power, from dynasthai to be able
Date: 1799
1also dy·nam·i·cal \-mi-kəl\ a : of or relating to physical force or energy b : of or relating to dynamics
2 a : marked by usually continuous and productive activity or change b : energetic, forceful <a dynamic personality>

Main Entry: dy·nam·ics
Pronunciation: \dī-ˈna-miks\
Function: noun plural but singular or plural in construction
Date: circa 1789
1 : a branch of mechanics that deals with forces and their relation primarily to the motion but sometimes also to the equilibrium of bodies
2 : a pattern or process of change, growth, or activity <population dynamics>
3 : variation and contrast in force or intensity (as in music)

the connections between different compartments, and how they interact affects the functioning of the whole
 

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Discussion Starter #19
intake tract before the throttle body via the driver's side nipple (DSN), intake manifold via the PVC hose, crankcase via the PCV valve and DSN which effectively ties ALL of them together, and cylinders via the piston rings, because they are tied together they are all interrelated....... when you modify the system you add or remove some of the chambers involved. A few of the chambers involved are purely for emissions reasons.

The orifices are the PCV valve, the DSN, the piston rings (yes, they are the passage from the combustion chamber to the crankcase), the TB, and we'll just leave it at that.

What's so unique about the relationship of an orifice to the containers it happens to be between anyway? We'll get into the pressures and where they are too.
 

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Discussion Starter #20
the smaller an orifice..... the more pressure it takes to move a given mass. Meaning at the same pressure the larger orifice will flow more, at the same FLOW the smaller orifice will require greater pressure to achieve the same mass flow as a larger orifice........... somehow this relates to turbos too and all kinds of shit

so..... on to the the throttle body because that is the main reason for the dynamic nature of the PCV system. With the throttle closed the intake manifold is in vacuum, it is connected to the PCV valve, the PCV valve is connected to the crankcase, and the crankcase is connected to the intake tract before the throttle body........ because the intake manifold is the lowest pressure point in the system air flows to it from the intake track, through the crankcase, to the intake manifold.

What happens to the vacuum in the intake when you floor the car?

it goes to 0, because the throttle body is an adjustable orifice, when it is open (essentially to the atmosphere) and isn't a restriction, the chambers (the intake and the atmosphere) reach equilibrium (the orifice/restriction the differential occurs at at that point becomes the intake valves, we'll get back to that later)

With the intake under vacuum the crankcase was being sucked clean. WTF happens at WOT? At WOT isn't there more blowby and pressure in the crankcase?
 
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