Turbo Glossery

[xXManwhoreXx]

Here are a few of the most common terms associated with a turbocharger system. Im not going to go crazy and define everything as most of you probably have a good understanding as to what everything already is. If you would like something added feel free to contact me and i will see that it gets put in. I will be adding additional segments over time.

A/R- A/R means area/radius. It is a formula to determine the size of the compressor and its turbine-housing confiruration. Sounds like a lot but to make it simply put, the smaller the A/R the faster your spool up time and the better your throttle response. But the down side is that the top end will suffer and choke off. If you have a large A/R you will be able to flow more air but you will experience a longer spool up time and poor response also known as turbo lag.

Blow Off Valve or BOV- A BOV is simply a valve between the turbocharger and the throttle plate that bleeds off extra boost pressure. Under certain conditions like when you shift gears or when you back out of the throttle the turbo keeps spinning yet the throttle plate is closed and the air is trapped. This will lead to the air pressure getting so great that it will actually force air backwards through the turbo causing what is known as compressor surge. This will cause a huge lag the next time you hit the gas or if you are boosting high enough it can actually bend compressor blades or even break the turbo shaft. A BOV will release this excess pressure. Another name for a BOV is a compressor bypass valve.

Compressor Surge- Compressor surge is when the air pressure in the charge pipes becomes so great that it forces air backwards through the turbo.

Intercooler- An intercooler is a heat exchanger in the intake tract that is used to cool the air that has been heated by a turbocharger or supercharger. There are several types including air-to-air and water-to-air intercoolers of which each has its pros and cons.

Trim- Trim is simply the size of the compressor wheel. There are many different variations and they are not only diameter but also height, weight, curvature, fin shape and several other factors. Just remember this, in general the larger the wheel the more more volume the turbo is capable of flowing. Whether it is on the intake side which will allow higher boost levels or on the exhaust which will create less back pressure in the exhaust system.

Volumetric Efficiency or VE- VE is the volume of the intake charge on the intake stroke versus the volume of the cylinder. This is always expressed in a percentage and the higher the percentage the better.

Wastegate- A wastegate is a devise that is used to regulate boost pressure. It is done by controlling the speed at which the turbocharger spins. The easiest way to do this is to route the exhaus tthe exhaust gases around the turbine whether it be back into the exhaust or vented to open air. Also by doing this a properly sized turbo will remain in its most effective speed range. A wastegate can be set to any boost level and will remain closed until that level of boost is reached. By doing this the turbo can use all of its available exhaust energy to reach maximum boost pressure.

SthPerformance from ef-Honda.com

[Oldsnut]

Dude learn to spell if you are going to start a thread. It's Glossary.

Just bustin your chops but if you are going to title a thread please spell it correctly Hooka Boy.

[xXManwhoreXx]

E and A my bad?? Why dont you fix it?

[xXManwhoreXx]

My 3 Turbo posts should be stickied... they will be extremely helpful to people who actually want to learn

[AleroB888]

Originally Posted by xXManwhoreXx

................
Volumetric Efficiency or VE- VE is the volume of the intake charge on the intake stroke versus the volume of the cylinder.

That doesn't make much sense as written....

I prefer Corky Bell's version:

".....the ratio of the number of molecules of air that actually get into a given volume to the number of molecules in an equal volume at atmospheric pressure."

or:

"[of an air pump] (engine or supercharger)....the actual volume the unit pumps divided by the theoretical volume it could pump.........

For a fixed-displacement supercharger, the theoretical volume is the displacement volume................"

Centrifugals and turbos are non-fixed-displacement, and have no theoretical pumped volume.

[wrestlingandrunning]

Ok do you still think this website is full of retards that never put the idea of turbo and alero together?