Car Tuning 101

200sxBoY

New member
Ok guys , since im an active member of the Tech Info forum , I noticed that something really important was lacking around here .
A sticky thread on DIY pages , performance theory's , step by step tuning for n/a and turbo/blowed engines , good car products depending on car brand , swap info , link's , etc etc ..
The goal of this thread would be to inform everyone on this forum of good link to help in their personnal tuning project . Many people here know lot's of thing , and i think that sharing our knowledge is the best way to make everyone smarter a bit .

So here's my contribution :

-Basic car knowledge
http://auto.howstuffworks.com/under-the-hood-channel.htm

-Horsepower/Torque explanation
http://auto.howstuffworks.com/horsepower.htm
http://www.nissanperformancemag.com/november98/torque.shtml

-Suspension
http://www.chris-longhurst.com/carbibles/index.html?menu.html&suspension_bible.html

-Fiberglassing
http://web.njit.edu/~cas1383/proj/main/
http://www.hotrodders.com/t52028.html
http://www.rqriley.com/frp-foam.html

-Turbo
http://www.stealth316.com/2-3s-compflowmaps.htm

-Electric Knowledge
http://www.bcae1.com/

-Books
Maximum Boost by Corky Bell : Turbocharging 101
Four-Stroke Performance Tuning by A. Graham Bell : N/A Engine Tuning 101
Forced Induction Performance Tuning by A. Graham Bell : Turbo engine building
Automath Handbook by John Lawlor : Basic car tuning , car related math's
Engineer To Win by Carroll Smith : Metalurgy/Car Dynamics , THIS BOOK IS A MUST *tu*
Please contribute to this thread , don't ruin it .
 
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This isn't a car related book but if you want to learn about material resistance and how heat treating works and that kind of thing: Machinery's handbook (also known as the bible of the mechanical industries)

Basics of engin management: http://members.aol.com/dvandrews/ems.htm#programems


More turbo basics: http://www.rtec.ch/turbo_basics.html

How boost controller work and how to make one: http://www.geocities.com/chmwatson/FAQs/mbc.html

Turbo tuning stuff: http://www.tuningtechnology.com/techinfo.html

Just started reading on this site: http://www.eng-tips.com/threadminder.cfm?pid=71
 
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-First Upgrades

Starting tuning a car is a decision lots of people take , You decide when you start and where you wanna stop .
So heres the first upgrade you should think about :

Intake
Upgrading the intake doens't really gives that much horsepower , in some case it just worsen the situation . Usualy it's gonna free some hp's in the top end (high rpm's) . Short ram intake are the less expensive one and perhaps they don't do much often . Cold air intakes are rated to free more hp's but they require cleaning more often

Exhaust
The exhaust is quite similar to the intake , it let's your engine breath better . And remember that the bigger ain't the better . There is a size of exhaust pipe for each engine . The more bends you got in your pipe the more the flow is disturbed , even with mandrel bent exhausts . Running with no cat will indeed increase exhaust flow but it's pretty polluant . Keeping the earth green is worth the loss of your 2-3 hp's .
Size i heard to fit the best for pipe size ( these are estimation ) :
110-140hp: 2"
140-185hp: 2"1/4
180-220hp: 2"1/2
210-265hp: 2"3/4
250-320hp: 3"
Those are the size that are suggested and they are pretty close to reality
However , increasing the size of the exhaust pipe after the cat often often gives some power , because the cat heats up the exhaust gas .

Cams
Good cams can often give some power to an engine , but matching the duration with an engine is not THAT easy ... I ain't really a pro on this so i'll just describe them fast . The thing i know is that you don't want exhaust reversion ( when your exhaust gas come back in the cylinder ) and over-scavenging ( when fresh air/fuel mixture is sent with the exhaust gas ) . Over-scavenging happens at high rpm , it cuts power output and fuel economy . If you change your cam's for more aggresive one you may have to remap fuel curve to optimize performance . Just try choosing the best cam for your engine because you want to increase performance in high rpm and you don't wanna loose bottom-end .

Exhaust Manifold
The exhaust manifold should be the extension of your exhaust port . it shoulnd't be smaller because it will cut flow . And the manifold should not start turning too abruptly , as this will also cause flow a problem . The more bend you have , the more flow is disturbed . 4-2-1 headers seems to improve more bottom-end , while 4-1 headers seems to give more top-end .

Intake Manifold & Throttle Body
The throttle body is an important part of your intake path , too big will kill bottom end and too small will kill top end . The best size is the one that gives the most overall power .
Intake manifold inlet tubes have to be matched to the engine . But in general , short big tubes gives more top end , while long small tubes gives more bottom end . But that's not always true because some engine reacts differently . The best way to know is with a flow test

Head Porting
Head porting should be done by pro's . And you ain't a pro cause you got a dremel tool. The best place to get this done is a shop with a flowbench that as real good feedback . Don't trust your friends that think they know how to do the job , go with the pro's .

Pulleys
Pulleys can free some extra ponnys , they make the accessory drag less power from the crankshaft by reducing the speed at which they run and are lightweight so they require less force to be moved . They are power gains , but not much .

Cooling
A bigger radiator while have more surface to cool your cooling fluid . If you upgrade things on your engine , heat may go up so this may be needed to prevent detonation . But don't upgrade it if it's not needed . Radiator cap with an higher bar rating can also help . By increasing the pressure in your cooling system , you increase your fluid boiling point .

Brakes
Even if your car goes faster , you have to stop it . Brake upgrade is a nessecity on any tuned car . Drilled/sloted rotors help by dissiping more heat , but tend to use faster . Bigger brake pads will help in braking because there is more surface rubbing to stop the rotor . Caliper rigidity is also important . Willwood is known to make good brake kits .

Suspension
When your lowering your car , it can change suspension adjustement . Camber and caster may be affected and this may make your car turn weird . When changing a suspension part it's rather important to get it aligned with the best setting so your parts will trully upgrade handling .

Lightweight Parts
Lighter wheels , flywheel and internals will help the engine reving by accumulating less inertia . Lighter wheels will also help braking and handling .
A lighter flywheel will help engine reving , but may feel less confortable . Gear change may less smoother compared to the stock one . Changing the clutch is important if you boosted your hp , because a stock clutch may have a hard time handling all this power .

*VTEC controller*
This is related a bit more to Honda's , but it's something quite important . Getting your VTEC to kick at 3000rpm is totally useless . This technology is made to get the best effiency at low and high rpm's . If the VTEC would have been usefull to low rpm , Honda would have made it kick at lower rpm .
However , I believe that if you really upgrade your car , the VTEC switch point may have to be changed to get the optimal performance . The VTEC switch point is where the bigger/longer lift is needed to help the engine breath .


That's it ( for now ) If you don't agree with something i writed or if i made a mistake , please don't flame . Just tell me and i will change the false information .
If you have more or better explained info , please post it so everyone will learn from it :bigup:
 
When you whant to go fast the thing to remember is wheight is your enemy. And the place you take off some weight is important.
Each time you take off one pound off any thing on the body is goog, but when you take off weight on sometings that spin like wheels and driveshaft/axel wheel its cout like 5 time the weight on the body for the car. When you take weight off somthind that aroud the motor like pulley, flywheel its count as then time the weight if it was on the body.
Its hard to explain here and in english but the thing is that you play whit the inertia of everything thats spinning.
The place you take weight is another thing to think you can play whit the balance of a car by putting or taking off some weight.

And biger is not always better when it come to a lot of car stuff
 
brake fluid
DOT3 brake fluid is the conventional brake fluid used in most vehicles.

DOT4 is similar to DOT3 except it has a higher boiling point and is less likely to absorb water.

DOT5 brake fluid is also known as "silicone" brake fluid. It’s NOT compatible with DOT3 or DOT4 systems. An upgrade to DOT5 fluid means you will need to replace your brake lines to be absolutely sure no DOT3 or DOT4 fluid remains. DOT5 has a lower boiling point than DOT4, it is also slightly compressible unlike DOT3 and DOT4. DOT5’s advantage is that it does not absorb any water at all. It’s other advantage is that it doesn’t damage paint the way DOT3/DOT4/DOT5.1 can.

DOT5.1 is a confusing name. It is not silicone and has nothing to do with DOT5. DOT 5.1 is a higher performance version of DOT3/DOT4. It has a higher boiling point than DOT4. It is compatible with DOT3 and DOT4 systems and does not require a change over of the hydraulic system to use.

ps:I did not write this.


If it's not good,I will delete it :D
 
Does anyone have any books to recommend on different block reinforcing techniques (for oldschool block, no sleeves). Like how to stop crank walk and stuff like that?

200SXBOY Good idea starting this thread. Thanks
 
try chapters at montreal on st-catherine street in the west of the town you gonna find here im a nearly sure they got this they have great technical book there
 
*Fuel Octane/Detonation*
Ok now , octane is something over-estimated . Some people think that by changing from let's say, 93 octane fuel to 98 octane fuel, performance will go up .
That ain't true. Octane is something that helps the engine compress the air/fuel mixture by avoiding detonation/pre-ignition. That's why in many supercharged/turbocharged engine you may want to raise octane fuel a bit so your engine doesn't detonate by the rise in air/fuel mixture injected in cylinder. Since detonation is a REALLY bad thing that can damage or even make your engine innoperationnal, it should be avoinded at all cost. Blown head gasket, connecting rod and piston are often the results of detonation .
The way i like to explain detonation , is that the air/fuel mixture overheats and self-ignite before a spark is launched, which creates unequal burn of the mixture and creates a big pressure on internals . Imagine, while your piston is going up, an explosion is pushing it down, that makes major stress on internal parts.
Also when using higher octane in turbo/supercharged engine, you can often increase psi's , but in order to achieve maximum performance, an ECU map for this octane grade will be needed.
Some people think that retarding timing to avoid detonation is a good thing to do but that's also false. A lower compression ratio is better then a retarded ignition.

I think this cover's a lot on fuel octane and detonation :D
 
Cams 101...given their importance in engine performance, I think cams are probably the most misunderstood components. A couple of definitions:

Valve lift: The distance that the cam lobe lifts the tappet (multiplied by the rocker arm ratio if applicable)

Duration: The time in crankshaft degrees (remember the cam spins at half the crank RPM) for which the valve is lifted off the seat. Duration is usually measured from .050" lift to provide a standard reference point.

Centerline: The actual phasing of the cam in relation to the crankshaft. This is given as the position of the center line of the #1 intake lobe in relation to the position of the #1 piston measured in crankshaft degrees after TDC.

Lobe separation angle: Basically the measurement in degrees of the angle between the intake and exhaust lobes. Intake and exhaust duration along with the LSA determine the amount of overlap; everything else being equal, a larger LSA will yield less overlap. A large amount of overlap will hurt low RPM performance for reasons mentioned above, but it can also can help volumetric efficiency at high RPM because of scavenging effects.

A common idea is that overlap bleeds off compression...overlap, by itself, will NOT hurt dynamic compression. Cylinder pressure is generated during the compression cycle, after the intake valve has closed and before the exhaust opens. Within practical limits, an early intake closing and late exhaust opening will maintain the highest cylinder pressure. By reducing the LSA for a given lobe duration, the overlap increases, but the cylinder pressure can be increased as well. Thus cylinder pressure/dynamic compression can actually increase in this scenario, by the earlier intake closing and later exhaust opening. Now, by increasing duration for a given LSA, the overlap will increase, the intake closing will be delayed, and the exhaust opening will occur earlier. This will decrease cylinder pressure, but the decrease/bleed-off of compression is not due to the overlap, but rather to the intake closing and exhaust opening events.
 
jfsanterre said:
Very good idea 200sxBoY :bigup:
Thanx , just keep the good post coming .
Don't be affraid to share what you know guyz , often what you think is stupid might enlighten many other people
 
Intercooler
Intercooler's are a wonderfull thing when it comes to forced induction. They lower intake air temperature by transfering heat to air outside of intake tubing. The reason your need to cool down this air are :
-To avoid detonation
-Cooler air is more dense ( more dense means more air :D )
-Turbo is a REALLY hot device and it heats up air when it compress this air
There is two types of intercooling possible and i will try to explain them the best i can. :D

Air-To-Air:
This one is pretty basic. It's like a big radiator but instead of liquid circulating in it , air compressed from the turbo is circulating in it. It's usually made of aluminium or copper ( aluminium is way better then copper IMO ). The biggest problem with Air-To-Air cooler is choosing the right one and designing it properly. Choose a too small and it will restrict flow , choose a too big and it's gonna cost you an arm and give you turbo lag. Designing it properly is really important if you wanna have maximum flow. The inlet tube must not be too 'edgy' ( hard to explain this one with words ). A good design is this one :
intercooler-tall_thumb.jpg

It's pretty simple and effective. Front mounting may be the best solution, but watch out for dirt or particles getting stuck in it, cause they will drop it's effiency.

Air-To-Water
Ok this one is quite similar to the Air-To-Air one , except for some details. It uses the same intercooler core, but instead of being mounted in free ambient air, it's mounted in a water-tank. The water-tank is connected to a pump and water is pumped in a radiator. The intake air transfers it's heat to the water, then water is pumper in the intercooler 'radiator', the water transfers heat to ambient air, then it return to the water pot. Theres many advantage to Air-To-Water cooling:
-It can reduce lag by reducing intake tubing volume.
-The water-tank containing the intercooler can be mounted almost anywhere.
-You can fill up your water tank with ice for drag events. ( But be bright , a pump works with water, not with ice )
-Very useful on rear-engined car, where Air-To-Air intercooler are harder to locate.
However, they are more complex to build and are heavier then Air-To-Air units, here's a couple of pictures:
0090_02mg.jpg

st165_intercooler.gif


That's all i can think of ( for now ). If your choose to upgrade your intercooling, think wisely because those things don't cost 129,99$ @ Canadian Tire.
 
Backpressure and tdc (top dead center)
For all the fan of the big fat exhaust that put a 3 inch exhaust line on their 1.6 or 2.0 liter n/a motor you will not be happy to hear this. Bigger exhaust dont go directly whit big hp. For all the motor you have a moment when the intake valve and the exhaust valve are open at this particulary moment if you d'ont have enough backpressure because of your big exhaust the fresh air and the gaz will pass directly in your exhaust and this will result in what we call a backfire(not all the time). When you buy an exhaust you need to pay attention to your motor because some motor have to many flow on the exhaust side(usualy Honda have this) and this could result of more sound when you lift your foot of the gaz pedal. If you buy a good exhaust line like a 5zigen one that cost more then a Mr muffler one whit a APC silencer you gonna have an exhaust thats been tested and calculated to have the corect flow and less sound for more power. So free flowing exhaust is not always better you need the good size for your car and you need a good timing if you dont whant to use gaz and fresh air to do backfire. Dont forgive that every flame that go out of the exhaust is not making power.
 
To further the point a bit, backpressure is not like sticking a potato up your exhaust or something, you need to look at the pressure waves travelling through the exhaust. Backpressure during valve overlap is just a positive pressure wave coming back to the exhaust valves after reflecting on an opening (which can be the muffler outlet, for example). For a constant power figure (aka ~constant mass flow through the exhaust), the larger the pipe is, the less pronounced the pressure effects will be. Depending on RPM and the stroke the engine is on, this can have positive or negative effects like said above.
 
Supernaut said:
To further the point a bit, backpressure is not like sticking a potato up your exhaust or something, you need to look at the pressure waves travelling through the exhaust. Backpressure during valve overlap is just a positive pressure wave coming back to the exhaust valves after reflecting on an opening (which can be the muffler outlet, for example). For a constant power figure (aka ~constant mass flow through the exhaust), the larger the pipe is, the less pronounced the pressure effects will be. Depending on RPM and the stroke the engine is on, this can have positive or negative effects like said above.

thanks i was having a litle trouble explaining my self in english
 
200sxBoY said:
-First Upgrades

.

Head Porting
Head porting should be done by pro's . And you ain't a pro cause you got a dremel tool. The best place to get this done is a shop with a flowbench that as real good feedback . Don't trust your friends that think they know how to do the job , go with the pro's .


Words to live by *tu*
 
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