TURBOCHARGERS EXPLAINED

ALL ABOUT TURBOCHARGERS

Turbocharger is a kind of forced induction machine that compresses the air going into the engine which results in more amount of air entering the engine and leads to more amount of fuel being added hence more combustion and power. In other words the concept of the TC is that if the air entering the engine is pressurized and more oxygen is added then it would lead to addition of more fuel and ultimately more combustion and power.

The TC has 3 major parts:

The Turbine Section
The Compressor Section
The Center Housing

The Turbine Section consists of the turbine housing that has the turbines. It is located on the exhaust manifold of the engine.

The Compressor Section consists of the compressor housing that has the compressor wheel. It is located in between the air filter and the intake manifold. The compressor wheel is a a type of centrifugal pump.

The Center Housing consists of the common shaft that connects the turbine section and the compressor section. It also consists of a fluid bearing wherein a thin layer of oil is on the connecting shaft that helps to cool the shaft(Excessive temperature is produced from the turbines) and rotate the shaft with less friction.

NOTE: Now the turbine in the TC of your car is similar to the gas turbine used on helicopters. The concept of a gas turbine is that the hot air obtained from the combustion in the engine spins the turbine and this leads to production of energy.

Working Of the TC:

The exhaust manifold emits the exhaust gases that enters the turbine housing wherein the speed of gas is increased. Then the gas flows through the turbine wheel and here it releases energy. This energy drives the common shaft that connects to the compressor section and thereby drives the compressor wheel. The compressor draws in air through the air filter and increases the pressure and density of the air and this increases the temperature of the air and hence hot air is pumped into the intake manifold and into the combustion chamber.


The TC pumps compressed hot air at high pressure into the engine where the air is compressed again by the piston. This would lead to very high temperature of the air and it might ignite the fuel before the spark plug does. This phenomenon is known as knocking and can be avoided by using higher octane fuel.


Advantages of a TC:

The TC is much more efficient when compared to the SC as it runs using the exhaust gases which would result in better combustion and decrease of emissions. Furthermore the TC is very useful in mountains as it helps the engine breathe easier with no compromise on power.
Disadvantages of a TC:

The TC does not give immediate boost and results in a lag known as turbo lag as it is run by the exhaust gases and not the crankshaft.

The power to spin the turbine is given by the exhaust and this increases the restriction of the exhaust as the engine has to actually work against a higher back pressure and this reduces a bit of the engine power.

Tips to decrease Turbo Lag:

The best way to decrease turbo lag is by decreasing the size of the turbo as a smaller turbo with smaller turbine will reduce the inertia of the spinning parts allowing the compressor to have quick acceleration. On the other hand a small turbo is useful only for low rpm gains and for high rpm gains a larger TC has to be preferred. Hence the best alternative will be to have two TCs for low and high rpm gains.

MODIFYING YOUR STREET CAR

ULTIMATE CAR MODS

Turbo Chargers:

Turbo Chargers are used to increase the density of air entering the engine thereby creating more power. The power gain achieved on simple turbos are around 7psi. Higher power in turbos requires forged internals that cost more. Some conditions have to be checked for installing turbos as:

1. The Engine Control Unit should be capable of handling the power on the turbo.
2. There has to be sufficient space under the hood to install a turbo.
3. Some cars require bigger fuel injectors in order to supply more fuel for proper charging.
4. Make sure to use good quality of fuel to prevent knocking and maintain pressure.

Furthermore the choice of the right turbo to suit the engine of a particular car is very important.
An inter cooler is also required to cool the engine and the radiator must be capable of handling high temperatures. Furthermore polished and ported engine heads increase the power of the turbo.

More information on various turbos for your car is at Garrett Turbos at www.turbobygarrett.com/


Super Chargers:

Super Chargers differ from Turbo Chargers in the fact that they are connected to the engine crankshaft and are activated as soon as the engine is started but on the contrary the turbos are driven by the exhaust. Due to this fact the SC offers power even in low rpms but TC offer power in high rpms and for a TC to offer power in low rpms you would have to go for a multi stage TC. However because the SC is connected to the crankshaft it leads to the increase in stress for the engine(just like how the ac puts load on the engine)

Both the SC and the TC have their own pros and cons but the TC is more preferred due the higher efficiency and higher mileage as compared to SC and because the TC can be tuned to our preference. Except for a MB Kompressor which has a really good SC the installation of a SC would be unnecessary.

More information on various SC's for your car are at Vortech SC's at www.vortechsuperchargers.com


Engine Replacements:

If you still need more power from your street car you can go on to change the engine but you need to be very careful as the replacement of the engine of a car is like a heart transplant. Remember to visit a proper tuner for an engine replacement. Some engine replacements will require heavy modifications that would cost a lot. Some popular engine replacements are:

1. Twin cam Swift engine for Zen
2. EVO engine for Lancer

Some good tuners are
Electra Performance - Chennai at www.electraperformance.com
Speed Works - Chennai at www.speedworksindia.com

Performance Brake Systems:

After all these performance upgrades your stock brakes will not be able to provide adequate braking which is when you need better bigger brakes. You could either buy total brake sets at brembo brakes at www.brembo.com or install performance brake pads and discs.


Gearbox Replacements:

Due to the increase in power you will require a new gearbox to extract more power. But the change of the gearbox will require new drive shafts.

More information on installing a performance gearbox is at Pfitzner Performance at www.ppgearbox.com.

Clutch Replacements:

Performance clutches are a necessary upgrade at this stage in order to achieve extra performance quickly but on the other hand it is better to install performance clutches based on your requirement either drags or street races.

More information on performance clutches are at Clutch masters at www.clutchmasters.com


Engine Control Unit Replacements:

The Engine Control Unit(ECU) is the brain of your engine and at this stage it is better to have a new performance ECU for increased performance. Installation of a new ECU requires a good tuner. The power increases to about 25% for a new ECU and the best option is to install a stand alone ECU which means that the stand alone ECU will build new ignition cam angles(for variable cam timing cars) and new ignition maps for your boosted engine but if you are not planning to make drastic changes in boosting your stock air flow a normal piggyback ECU will be fine in your car.

Other Mods for your car:

1. A fire extinguisher will be a handy tool in any case of accident.
2. Racing Seats from Sparco or Momo with 5 point harness are recommended.
3. Roll cages help maintain stability of the car.
4. Temperature, Oil Pressure and boost meters help keep an eye on the engine.

MODIFYING YOUR STREET CAR

SECONDARY MODS:

Suspension Kits:


Due to the increase of power in your street car it would need better suspension in order to provide grip and safety. You can change to performance struts, shocks, dampers, coils and camber kits.


The details of performance suspension kits are at www.eibach.com/



Nitrous Oxide Systems:


This is a very zippy mod preferred by drag racers and it has to be carefully handled. Now the concept of NOS is that when nitrous and fuel are injected into the engine's cylinders it expands and exerts high pressure on the pistons leading to a surge in speed.There are two types of nitrous oxide systems as WET and DRY systems.


There are three subtypes in the wet system as:


1. Wet Single Point: This introduces the fuel and the nitrous together thus causing the upper intake to become wet with fuel. The wet nozzle differs in the way that it intakes the fuel and nitrous in metered jets to create the right air fuel ratio.


2. Wet Direct Port: This introduces the nitrous and fuel directly into each intake port of the engine.They combine nitrous and fuel in several nozzles and that meters the fuel and nitrous mixture to each cylinder. Since the nitrous and fuel mixture is directly injected into the cylinder it is called the direct port system.


3. Plenum Bar: This system has spraybars in the plenums of the intake manifold. This system is simillar to the direct port multi stage nitrous systems.


DRY NOS:

In this system the fuel is introduced through the fuel injectors. This can be altered by altering the pressure in the fuel injection system or altering the time the fuel injectors remain open. This system has only one nozzle and that sprays only nitrous and not nitrous and fuel.

More info on NOS is at http://www.nitrousdirect.com/ and http://www.holley.com/index.asp



Head Porting:

This means increasing the size and polishing the intake and exhaust ports. The intake ports need to have a rough finish and the exhaust ports need a polished finish. There is increase in power due to the increased quality of gas flows.



Camshafts:

They lead to at least a 15% increase of power and you can customize them for high or low or mid rpm gains. Try getting them with a cam limiter so as to achieve full cam gains. You could also go for high lift cams if you want a bang for bucks.


Rev Limiters:

Get the rev limiters removed from a tuner. The rev limiter is placed by the car manufacturer and if removed will not lead to increase of power but helps to hold a gear longer. But check if your engine can hold the excess stress.


Over Boring:

This means to increase the displacement (cc) by increasing the size of the piston and the engine stroke. The simple concept is that bigger the engine, more the power. In order to do this change your crankshafts, pistons and the connecting rods.



Engine Control Unit Mods:

This means the addition of another ECU called as the piggyback ECU. The concept is that the piggyback ECU does all the performance work and the car's ECU does all the non engine electronic jobs. The piggyback ECU modifies the fuel injection and timings leading to increased performance.

On the other hand a box called the Pete's Tuning Box can also be added between the engine and the ECU and this box modifies and sends false signals to the ECU asking for more fuel for more combustion and eventually increase of power.



Engine Remapping:

You could go for an engine remap with an experienced tuner. This means that the default factory software settings will be modified according to your demands. It is recommended that the engine remapping job is done after the above given mods are done.




REMEMBER: WARRANTY WILL BE VOID IF THESE MODS ARE DONE WITHIN THE COVERAGE TIME

MODIFYING YOUR STREET CAR

PRIMARY MODS

TIRES:

Tires constitute the initial modifications for any car since they provide adequate grip for cornering and braking at high speeds. Here are some parameters for choosing the best tire for your street car.

* Opt for tubeless tire since they are more advanced.

* Regarding the tire size(eg. 205/55/15)
205mm - Width of tread
55(%) - Height of sidewall in percent
15inch - Rim diameter of tire

* Go wider if:
1. You corner at high speeds.
2. Your car has a lot of power.
3. You want improved braking distances.

* Do not go wider if:
1. You drive in wet conditions.
2. You care about fuel economy.
3. You drive in busy traffic.

* Tread Pattern:

1. Conventional Tread : This refers to the stock tread pattern(stock tires)

2. Uni directional Tread : Have A or V configuration and usually uni directional.
Help control tire noise.

3. Asymmetric Tread : Have outside road facing sidewall and inside car facing sidewall due to which help in high speed cornering.

* Overall Tire Quality : These points are taken into consideration.

1. The reputation of the tire manufacturer matters a lot since all of them have special technologies.

2. The date of manufacture of the tire is given on the tire(eg. 2109 means the tire was manufactured in the 21st week of 2009) Never buy tires older than a year. The newer the tires the better.

Some popular tire manufacturers are

Yokohama Tires at http://www.yokohamatire.com/

Michelin Tires at www.michelin.in/

Apollo Tires at www.apollotyres.com/


AIR FILTER:

The air filter in your street car can be changed very easily and gives only a very little change in performance.

On the contrary a cold air intake(CAI) is a true performance mod and the concept here is that even if it is more than 30 degrees outside its still cooler than under the hood and the CAI intakes this cold air. There are a few points to be remembered in installing a CAI

1. The pipes used should be mandrel bent aluminum pipes and the length of these pipes should be greater than the throttle body.

2. The installation of CAI also leads to significant increase in noise levels.

3. For use in dusty conditions a shroud maybe used.

Some popular air filters available are:

K&N Air Filters at http://www.knfilters.com/

Piper-cross Air Filters at http://www.pipercross.net/


SPARK PLUGS:

Spark plugs give nearly no noticeable difference in the performance of your street car. In any case go for Iridium spark plugs with the correct heat range to suit your engine.

Some spark plug dealers are:

NGK Spark Plugs at www.ngkntk.in/ngkindia.htm


FREE FLOW EXHAUST:

The free flow exhaust helps your car breathe efficiently resulting in increase of performance.
Some points to remember in installing a free flow exhaust are:

1. Ask for a good header design to suit low to mid range rpms as you cannot speed a long time in higher rpms.

2. Take note of the catalytic converter or the mid muffler because many tuners may remove this and it might lead to violation in the emission norms.

3. Try and get a complete free flow kit along with the headers for good performance.


TEMPERATURE SIGNAL MODIFIERS:

They send false signals to the ECU and this leads to alteration in the fuel and ignition maps. They give only a narrow difference to the performance of your street car.


SYNTHETIC ENGINE OIL:

Synthetic engine oils offer superior lubrication to your engine as they are chemically prepared with polyalphaolefins and synthetic esters. Hence they offer increased engine life and offer lubrication even in redline revs.


NOTE: All Porsche engines are fitted with synthetic oils.

Some synthetic oils available are:

Mobil 1 at www.mobiloil.com/


SHORT SHIFTERS:

They shorten the throw of your street car's gear lever and result in faster gear shifts. Also take into account the ergonomics as it would take some getting used to and many people would be better off with the stock shifters.


PROJECTOR HEADLAMPS AND LED TAIL LIGHTS:

Projector headlamps are a useful mod for people who like visual mods. The actual advantage and disadvantage in using projector headlamps is still under controversy. In any case it is better to go for double projected headlamps and use HID bulbs for better visibility. You could go for Bosch HID kits but there is an issue of the low beam not being bright enough. The best option would be to put:

* HID bulbs on the projectors for high beam and Osram Night Breakers for the low beam

Regarding the installation of LED tail lights, these are a totally visual modification.

More detailed information can be got at www.boschindia.com


REMEMBER: POWER IS NOTHING WITHOUT CONTROL