Turbo Terminology Explained...
03-31-2003, 08:46 PM
#1
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O.K. who wants to do it? I've heard alot of people asking questions about this and I'm curious myself.
What do these things mean?
Inducer
Exducer
A/R
Wheel trims (P,Q,R...)
Clipping
Dynamic, carbon seals
And who wants to explain how to read compressor maps?
Heres my guess about what these mean. Inducer is the size of the top of the compressor/exhaust wheel? Exducer is the size of the base of the wheel? The trim is the angle that the blades are tilted? And A/R is the amount of air the housing can compress?
What do these things mean?
Inducer
Exducer
A/R
Wheel trims (P,Q,R...)
Clipping
Dynamic, carbon seals
And who wants to explain how to read compressor maps?
Heres my guess about what these mean. Inducer is the size of the top of the compressor/exhaust wheel? Exducer is the size of the base of the wheel? The trim is the angle that the blades are tilted? And A/R is the amount of air the housing can compress?
03-31-2003, 08:59 PM
#2
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I was gonna see if we got some real answers before I requested that, but good lookin out 
Heres what Clipping is:
Clipping is the technique of cutting away some of the material on the fins of the impeller wheel of the turbocharger. In other words, to 'clip' a turbo is to make the fins in the exhaust path smaller. The cut is usually done at an angle of between 10 and 20 degrees - the bigger the angle, the more material is removed from the fins.
This may seem like a dumb thing to do, since smaller fins mean that the exhaust gases will impart less force to the turbine wheel and consequently increase turbo lag. This is true, but the benefit of clipping is found in the high RPM range of the motor. At higher RPMs, the turbo may have already surpassed the required user-set boost levels and is not contributing to engine power.
Since the impeller wheel in the exhaust stream partially blocks the exhaust gas flow (by design), it can act as a significant restriction at high RPMs, when the exhaust flow rate is highest. Clipping the turbo reduces this restriction and allows more air to flow past the turbo wheel at high RPMs, thereby improving airflow through the engine and increasing top-end response.
Heres what Clipping is:
Clipping is the technique of cutting away some of the material on the fins of the impeller wheel of the turbocharger. In other words, to 'clip' a turbo is to make the fins in the exhaust path smaller. The cut is usually done at an angle of between 10 and 20 degrees - the bigger the angle, the more material is removed from the fins.
This may seem like a dumb thing to do, since smaller fins mean that the exhaust gases will impart less force to the turbine wheel and consequently increase turbo lag. This is true, but the benefit of clipping is found in the high RPM range of the motor. At higher RPMs, the turbo may have already surpassed the required user-set boost levels and is not contributing to engine power.
Since the impeller wheel in the exhaust stream partially blocks the exhaust gas flow (by design), it can act as a significant restriction at high RPMs, when the exhaust flow rate is highest. Clipping the turbo reduces this restriction and allows more air to flow past the turbo wheel at high RPMs, thereby improving airflow through the engine and increasing top-end response.
03-31-2003, 10:14 PM
#3
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From what I understand clipping the turbo's would be equivant to upgrading the exhaust A/R. So if you already had a 1.0 A/R, you would basically have the equivalant to a 1.15 A/R, depending on the percentage of clip.
P trim is what is normally used on street cars. Q trim flows more exhaust and is more for heavily ported cars or bridgeports. You don't want a P trim on a bridgeport, cause after a certain boost level the turbo will actually begin to cause too much backpressure and result in a loss of power.
Umm, inducer is compressor, exducer is exhaust. A/R is how the turbo is measured, either on the compressor (intake side) or exhaust side of the turbo.
P trim is what is normally used on street cars. Q trim flows more exhaust and is more for heavily ported cars or bridgeports. You don't want a P trim on a bridgeport, cause after a certain boost level the turbo will actually begin to cause too much backpressure and result in a loss of power.
Umm, inducer is compressor, exducer is exhaust. A/R is how the turbo is measured, either on the compressor (intake side) or exhaust side of the turbo.
03-31-2003, 10:18 PM
#4
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Originally Posted by 94touring' date='Mar 31 2003, 11:14 PM
Umm, inducer is compressor, exducer is exhaust. A/R is how the turbo is measured, either on the compressor (intake side) or exhaust side of the turbo.
03-31-2003, 10:21 PM
#5
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Originally Posted by 1Revvin7' date='Mar 31 2003, 08:18 PM
I thought the exducer is the base part of the compressor wheel and the exducer is the upper half of the compressor wheel?
04-01-2003, 04:07 AM
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04-01-2003, 05:54 AM
#9
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Inducer = small side (inlet) of compressor wheel
Exducer = small side (oulet) of turbine wheel
The large part of either wheel is refered to as the major.
The A/R refers to the housings only. Area divided by radius at any point is a constant ratio.
Exducer = small side (oulet) of turbine wheel
The large part of either wheel is refered to as the major.
The A/R refers to the housings only. Area divided by radius at any point is a constant ratio.