To start off, an explanation of a turbocharger is in order.
This is a Garrett Turbocharger. As you can see, it is made up of two sides. One side expels the exhaust gasses through a downpipe which leads to the exhaust, and the other takes in air through an intake and expels it through the chargepipes eventually ending at the intake manifold.
A turbocharger works by compressing the air flowing into the engine. The advantage of compressing the air is that it lets the engine squeeze more air into a cylinder, and more air means that more fuel can be added which in turn will lead to more power in each explosion.
For a Turbocharger to achieve this compressed air, the turbocharger uses the exhaust gasses from the engine to spin a turbine, which in turn spins an air pump. The turbine in the turbocharger spins at speeds of up to 150,000rpm. Because it is exhaust that is turning the turbine, the turbocharger gets extremely hot and needs to be cooled down by either oil, coolant or both.
here is another basic diagram of a turbo setup:
and here is a diagram of an actual turbocharger:
Now that you know how a turbocharger actually works, lets learn some of the terms that will be used in the rest of the writeup. some of these are the technical names, some are just abreviations used for ease of reading.
Turbo - Short for turbocharger, the main part of the system
Spool - The action of the turbo spinning the compressor to creat compressed air
Boost - The name for the compressed air the turbo makes
Intercooler - Like a radiator, but used to cool the charged air.
FMIC - A common type of intercooler, stands for Front Mount Intercooler
BOV - Short for Blow-off valve (this will be explained later)
Wastegate - A devise that bleeds off exhaust before the turbo so that it will not spool while idling.
Boost creep - When compressed air hits the throttle plate while idling
Idling - When the car is not moving but the engine is on
Dyno - A device used for measuring horsepower and torque numbers of a car
Tuning - The art of playing with a cars settings to make it run at the optimum ability
Chargepipes - The piping used to carry the compressed air to the engine
Dump tube - A single ppe that carries exhaust from the wastegate out of the engine bay
PSI - Pound Per square inch (mesurement of presure)
BASIC COMPONENTS OF A BASIC SETUP
So now you know your terms, lets build our first setup!
Here is a list of every part in a basic setup and a description of what it does:
TURBOCHARGER - The actual device that compresses the air:
- A special exhaust manifold, unlike the stock manifolds, these have a connection for the turbo and also for the wastegate, here are a few examples:
- The pipe that goes from the exhaust side of the turbo down through the engine bay and then connects to the catalytic converter and then out through the exhaust.
- As mentioned earlier, an itercooler is like a radiator, but for air. air flows through it and then compressed air is pumped through the inside of it. They can come in many shapes sizes and forms, as well as placements. For example, on a stock Subaru STI, the ntercooler is placed under that giant hoodscoop, whereas on a Neon SRT-4, it is mounted in the front bumper.
- A wastegate is a device that sits on top of the exaust manifold, before the turbo and when a certain presure is reached, the wastegate bleeds off exhaust gasses from the engine in order to stop the turbo from making more boost. It is very important to manage this because a turbo making too much boost will bow your engine in a second. A popular brand of Wastegate is Tial and Turbonetics. Noramlly they come with a spring rated for a certain PSI. This can be altered with a boost controller. Some turbos have a built in wastegate, although most peopel prefer to run an external wastegate so it can be adjusted easier.
BOV (blow-off Valve)
- A BOV is a device that will releive presure from the chargepipes after the driver lets off the gas. This prevents boost from building up and either hitting the throttle plate or spinning the turbine in the wrong direction, which is BAD. BOV's come in many shapes sizes and forms. It is up to you which one you choose, although Greddy make some of the most well known styles.
- The most simple part of the setup... the pipes that carry the compresed air from the compressor side of the turbo to the intake manifold. Although a simple concept, once making a high powered turbo setup, length of pipes, diameter, degree of bends all come into play. Aluminum is what most pipes are made from.
- In order to move more fuel into the engine, new fuel injectors are needed. on a simple syste, 450cc injectors are sufficient, although some high powered cars can run injectors upwars of 1200cc's.
- Arguably the most important part of a turbo application is how the engine is managed. since there are so many ways and so many combinations of setups and devices, here is a list of the most common components, some standalone and some that need to be used together with other parts.
AEM Engine management System
MSD Boost timing mangaement
Map sensor missing link
As you can see, there are a few different ways to go. most likely, as i have found, the best way seems to be to go with a obd2 - obd1 conversion. To explain this, I will quote something i wrote in a recent thread:
"there is obd0 obd1 and obd2.
obd0 would be on i think any car before 1991, obd1 would be til around 95, and obd2 from then on.
obd reffers to the electrical system used in a car ie. the ecu and other ocmponents that control the cars functionality. the reason that you would have to convert a car to obd1 from obd2 to run a turbo setup is because the ecu's are far less complex and they are supported for chipping. now, the way you go about converting a car to obd1 or even obd0 (if your car was obd1) is by buying a new ecu and a new harness.
a harness is what plugs into the ecu from every single wire in the car that controls soemthing.
harnesses normally run about 70-100 dollars and come in many verieties. if you are a good electrician you can make your own fairly easy, but you need some good soldering skills.
the next part, and most important is the ECU. the ECU obviously is what controlls the cars functions. on our cars, the ecu is already preset to do things a certain way, but once you introduce the tunability of the ecu with something such as hondata, you are able to modify things. this is where you hear people mentioning taking off the speed limiter on the car. its all in the ECU.
if you are going to run a turbo or forced induction system on your car, one of the best things you can do is run a chipped ECU. for us accord owners, the ecu of choice is a P28 which i beleive is from a civic, although it could be from a teggy.
now once you have your ecu, it needs to be chipped, as you would with a games console, so you can modify setings. there are a few different types of tuning software you can use: chrome, hondata, uberdata (a copy of hondata), NepTune etc etc...
for my car, im using NepTune, a fairly new system for tuning. since i am not doing a transmition swap and i am looking to build a car for luxury and fun not for high speed, i will be keeping my stock auto tranny, until it dies when i will be getting a new one from Dr. Evil transmisions. anyway... neptune lets you tune he shift points, rpm limits, stall speeds and other vital settins on an automatic transmition, whereas most other tuning software will not.
anyway, once tuned to your needs, the ECU will have a map of the fuel/air ratios and other such settings. Of course with forced induction, the more air you push into the engine, the more fuel is needed. this is the job of a tuned ecu. although saying that, companies such as Apexi offer something called an AFC which manages the fuel injectors from a little computer in your car, mounted on your dash."
As I said before, this is what I think is the best and most complete way of running a turbo setup on our vehicles, but that can all be varied between each person with a turbo setup. Its all a matter of personal preference.
- Obviously, a guage monitors something. For a basic setup, a boost gauge is a must. There are many other gauge types out there, just look at what there is and see what you think you will need to monitor the most.
- Lastly, tuning is the final step in the turbo process. Although it is not an actual item, it is what will make your car run without issues and at the best performance possible. Normally, a tune would be done at a special shop with a dyno to mesure all the cars numbers and details. More can be found out on this by looking up your local tuning shop and calling or emailing them.
SHOULD I BUY A KIT OR GET THE PARTS INDIVIDUALLY?
This is a question that can only really be answered on your own. While i can suggest that you piece together your kit after A LOT of research, the natural thing would be to get a premade kit for your car and just bolt it on. Unfortunately as many people will tell you, it is not that simple. As well as that, kits are noramlly made with substandard parts and are overpriced. a good kit can be pieced together for our cars for about $3000. a kit may cost a few hundred less then that, but you do not get half the quality parts you would if you did it yourself.
a few examples of companies that make kits for our cars are:
There are however, other manufacturers that make kits. one being the natorious SSAUTOCHROME. if you ever see that name on anything you are looking at buying, go wash your ees out with soap.
if you are wondering why i warn you so much about not ever ever ever buying something made by them, let these photos do the talking...
yes, that turbo is completely cracked in half. feel safe putting that in your Accord?? thought not.