What is "boost", and how related to turbo or S/C?
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From: West Hartford
What is "boost", and how related to turbo or S/C?
Please excuse my ignorance.
I hear a lot about "boost" or psi in the engine, especially in conjunction with Turbo's or S/C.
My question is what does boost mean in real terms? I understand PSI but am not sure if that is the same as boost. Also what is the normal boost or psi for the S2000?
Also what are the risks of increasing the boost?
Hobb
I hear a lot about "boost" or psi in the engine, especially in conjunction with Turbo's or S/C.
My question is what does boost mean in real terms? I understand PSI but am not sure if that is the same as boost. Also what is the normal boost or psi for the S2000?
Also what are the risks of increasing the boost?
Hobb
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From: Ventura County
My non-technical explanation of boost is whenever you add Forced Induction to the engine. Forced induction being turbocharger, supercharger, Nitrous. Whenever youre creating horsepower by methods other than relying solely on the construction of the engine.
A turbo and supercharger are similar in terms of feeding extra air to the engine for more power. Nitrous is the chemical used to enhance combustion (if I am right on this one) to get more power.
Boost and Psi are used interchangeably most of the time when referring to forced induction. Our stock S2000's do not have "boost" until you add the turbo or supercharger
Since our compression ratio is rather high (11:1), we can only boost about 6-7 pounds or psi before we reach detonation, ...an uncontrolled explosion within our cylinder walls. Definitely something that you dont want...because detonation can severly damage an engine.
Risks of boosting are (1) detonation, (2) Piston Ring failure (3) engine failure (4) speeding tickets.
and etc....which I am too lazy or unqualified to answer.
hope this helps
A turbo and supercharger are similar in terms of feeding extra air to the engine for more power. Nitrous is the chemical used to enhance combustion (if I am right on this one) to get more power.
Boost and Psi are used interchangeably most of the time when referring to forced induction. Our stock S2000's do not have "boost" until you add the turbo or supercharger
Since our compression ratio is rather high (11:1), we can only boost about 6-7 pounds or psi before we reach detonation, ...an uncontrolled explosion within our cylinder walls. Definitely something that you dont want...because detonation can severly damage an engine.
Risks of boosting are (1) detonation, (2) Piston Ring failure (3) engine failure (4) speeding tickets.
and etc....which I am too lazy or unqualified to answer.
hope this helps
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From: Santa Clara
Lots of questions in there.
"Boost" refers to the pressure generated by a turbo- or super-charger. Turbos and superchargers increase horsepower by compressing the air flowing into your engine. Compressing the intake air makes more oxygen available, so you can burn more gas, and generate more power.
Boost is measured in any unit of pressure. PSI is obviously standard in the States, but you can just as easily measure boost in kPa or atm or mmHg.
When someone says they're "running ten pounds of boost," they mean their forced-induction system is creating an intake pressure 10 psi above what it would be without the forced-induction system. (Note: atmospheric and intake pressures are not the same -- your engine creates a vacuum, and draws intake pressure below atmospheric pressure. As indicated above, you measure boost as additional pressure above the pressure that would normally be present in the intake.)
The stock S2000 is naturally-aspirated, and does not have any boost.
The risk of increasing boost is that it can cause detonation or pre-ignition of the fuel in the cylinders. Essentially, the fuel/air mixture can spontaneously ignite at a temperature dependent upon its pressure. Higher pressure leads to lower spontaneous ignition temperature. When you boost too much, the fuel explodes before the spark plug fires, during the compression stroke, in a very damaging situation known as pre-ignition. The other possibility is that the very high-pressure air/fuel mixture may explode, rather than burn smoothly. This shocks the pistons, and leads to their failure. This is known as detonation, or knock.
The other main worry with boosting is that the additional cylinder pressures put extra wear on the piston rings and valves, which have to seal the cylinder during the compression and power stokes.
Hope this helps.
- Warren
"Boost" refers to the pressure generated by a turbo- or super-charger. Turbos and superchargers increase horsepower by compressing the air flowing into your engine. Compressing the intake air makes more oxygen available, so you can burn more gas, and generate more power.
Boost is measured in any unit of pressure. PSI is obviously standard in the States, but you can just as easily measure boost in kPa or atm or mmHg.
When someone says they're "running ten pounds of boost," they mean their forced-induction system is creating an intake pressure 10 psi above what it would be without the forced-induction system. (Note: atmospheric and intake pressures are not the same -- your engine creates a vacuum, and draws intake pressure below atmospheric pressure. As indicated above, you measure boost as additional pressure above the pressure that would normally be present in the intake.)
The stock S2000 is naturally-aspirated, and does not have any boost.
The risk of increasing boost is that it can cause detonation or pre-ignition of the fuel in the cylinders. Essentially, the fuel/air mixture can spontaneously ignite at a temperature dependent upon its pressure. Higher pressure leads to lower spontaneous ignition temperature. When you boost too much, the fuel explodes before the spark plug fires, during the compression stroke, in a very damaging situation known as pre-ignition. The other possibility is that the very high-pressure air/fuel mixture may explode, rather than burn smoothly. This shocks the pistons, and leads to their failure. This is known as detonation, or knock.
The other main worry with boosting is that the additional cylinder pressures put extra wear on the piston rings and valves, which have to seal the cylinder during the compression and power stokes.
Hope this helps.
- Warren
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From: Santa Clara
As a clarification:
Nitrous is quite definitely not a form of boost. Nitrous oxide is simply a gas which provides additional oxygen. Your car can then burn more fuel, and produce more power.
However, the term "boost" is used only for forced-induction systems, and refers to added intake pressure.
- Warren
Nitrous is quite definitely not a form of boost. Nitrous oxide is simply a gas which provides additional oxygen. Your car can then burn more fuel, and produce more power.
However, the term "boost" is used only for forced-induction systems, and refers to added intake pressure.
- Warren
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From: Santa Clara
I'm not completely sure I can accept that nitrous is a form of forced induction.... forced induction refers again to air pressure. In my opinion, nitrous is a completely unrelated technique.
In either event, it doesn't have much to do with Hobb's question.
- Warren
In either event, it doesn't have much to do with Hobb's question.
- Warren
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[QUOTE]Originally posted by chroot
[B]...
When someone says they're "running ten pounds of boost," they mean their forced-induction system is creating an intake pressure 10 psi above what it would be without the forced-induction system.
[B]...
When someone says they're "running ten pounds of boost," they mean their forced-induction system is creating an intake pressure 10 psi above what it would be without the forced-induction system.
