DESCRIPTION OF THE PRIOR ART
[0002] Excess exhaust backpressure is detrimental to vehicle engine performance. It is known that reducing restrictions to the flow of the combustion by-products (exhaust) from the combustion chamber of an internal combustion engine yields considerable improvements in the torque and power outputs, and the fuel, volumetric and thermal efficiencies of the engine.
[0003] The removal of the exhaust gases from the combustion chamber using the momentum of the exhaust gases in a long exhaust pipe, or by taking advantage of the pressure waves set up in the exhaust pipe by the discharge of the previously expelled gases, is known as scavenging. In addition to improving the exhausting of the combustion chamber, this scavenging effect also works in conjunction with the vacuum created by the piston during the inlet stroke, to assist in drawing in a fresh fuel charge.
[0004] Exhaust manifolds adapted to maximise scavenging effects are often known as `extractors` or `headers`.
[0005] A well-designed extractor manifold comprises a plurality of bent steel pipes (one per cylinder), physically arranged so as to promote this scavenging effect. The pipes are also arranged in a fashion that consolidates them, so that there is only the one pipe channeling exhaust from that manifold to the rear of the car for release. These branches of pipes must therefore be consolidated at pipe connections or Junctions. For example, extractors for a six cylinder engine may incorporate three 2 into 1 junctions, and a further 3 into 1 junction further downstream.
[0006] It is an object of this invention therefore to provide an exhaust extractor manifold that provides improved scavenging, or at the least provides the public with a useful alternative to the exhaust manifolds of the prior art.
[0007] Other objects and advantages of the present invention will become apparent from the following description, taken in connection with the accompanying drawings, wherein, by way of illustration and example, an embodiment of the present invention is disclosed.
SUMMARY OF THE INVENTION
[0008] In one form of this invention, there is proposed a venturi pipe for insertion in a pipe of an extractor manifold so that exhaust gas will pass there through, the venturi pipe including a portion having a locally reduced internal diameter and a portion that is adapted to promote the swirling of exhaust gas passing there through.
[0009] Preferably, the portion having a locally reduced internal diameter is at or toward an upstream end of the venturi pipe, and the portion adapted to promote swirling of exhaust gas passing there through is at or toward the downstream end of the venturi pipe.
[0010] In a further form, the invention may be said to lie in a portion of a pipe of an extractor manifold including a portion having a locally reduced internal diameter, and a portion that is adapted to promote swirling of exhaust gas passing there through.
[0011] Preferably, the portion adapted to promote swirling of exhaust gas passing there through is downstream of the portion having a locally reduced internal diameter.
[0012] In a further form, the invention may be said to lie in a connector portion for an extractor manifold having an upstream end adapted to accept at least two converging upstream supply pipes, where said connector pipe defines a substantially helical path in a downstream direction.
[0013] Preferably, the connector portion has an upstream end with an outer perimeter shape which substantially matches the outer perimeter shape of the converging supply pipes, there being a bulbous portion for each supply pipe, where each bulbous portion is progressively less outwardly protruding in a downstream direction, but also veering in a curved path which is for each and all of the bulbous portions in a same handed direction.
[0014] Preferably, the respective bulbous portions define together a helical path in a downstream direction of the single pipe.
[0015] In a further form, the invention may be said to lie in an exhaust extractor manifold assembly including at least two upstream pipes converging at a pipe having a connector portion, the connector portion having an upstream end that is adapted so as to accept the upstream pipes and define a substantially helical path in a downstream direction, the assembly further including a venturi pipe having a portion of locally reduced internal diameter and a portion that is adapted to promote swirling of exhaust gas passing there through, wherein the venturi pipe is inserted in a pipe of the assembly in a position located downstream of the connector portion, so that the connector portion and the venturi pipe are adapted to co-operatively define a substantially helical path for exhaust gasses in a downstream direction of the connector portion.
[0016] Preferably, the helical path defined by the venturi pipe and the bulbous portions are adapted to generate a vortex in exhaust gases passing through the assembly, which will augment the scavenging affect provided by the extractor manifold.
[0017] In a further form, the invention may be said to lie in an exhaust extractor manifold including at least two upstream pipes converging at a connector portion, the connector portion having an upstream end that is adapted so as to accept the upstream pipes and define a substantially helical path in a downstream direction, the assembly further including portion of pipe having a portion of locally reduced internal diameter and a portion that is adapted to promote swirling of exhaust gas passing there through, wherein said portion of pipe is in a position located downstream of the collector pipe so that the connector portion and said portion are adapted to co-operatively define a substantially helical path for exhaust gasses in a downstream direction of the connector portion.
[0018] In a further form, the invention may be said to lie in an installation in which there is an internal combustion engine, with an extractor assembly having one or more of the above-mentioned features.
http://www.freshpatents.com/Exhaust-ext … 095056.php
Skillnad mellan extraktor grenrör och vanligt gjutjärn grenrör ?
You don't get another chance, Life ain't a nintendo -
Thiger_84
18 januari 2009
· 509 Inlägg
When the eagles are silent, the parrots begin to jabber.
YeahBitch
18 januari 2009
· 730 Inlägg
Canarion skrev:
http://www.sorman-racing.com/vedbod_file/avgasror_senaste.pdf
Hjälp på traven:)
Bra läsning de där 
ก้้้้้้้้้้้้้้้้้้้้ ก็็็็็็็็็็็็็็็็็็็็ กิิิิิิิิิิิิิิิิิิิิ
Audi <3
Audi <3
Audi A4 Quattro Stcc Edition (2004)
Thiger_84
18 januari 2009
· 509 Inlägg