any difference between 4 bolt and 5 bolt turbine
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is the 5 bolt better then the 4 bolt turbines?
im doing some research for a turbo setup im going to piece together and someone told me that the 5 bolt one is better but didnt give me a reason why.
tried searching with no luck, and i know this is a odd question but anyone got any info on this?
im doing some research for a turbo setup im going to piece together and someone told me that the 5 bolt one is better but didnt give me a reason why.
tried searching with no luck, and i know this is a odd question but anyone got any info on this?
from what i understand......
the 4 bolt is "better" than the 5 bolt, because there is no "wastegate hole" to cause any disruptions in the exhaust gas flow.
the 4 bolt is "better" than the 5 bolt, because there is no "wastegate hole" to cause any disruptions in the exhaust gas flow.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Dturbocivic »</TD></TR><TR><TD CLASS="quote">from what i understand......
the 4 bolt is "better" than the 5 bolt, because there is no "wastegate hole" to cause any disruptions in the exhaust gas flow.</TD></TR></TABLE>
It doesn't matter for the wastegate hole because if you're using a weld flange for the 5 bolt, it will completely seal that hole regardless.
The only advantage of the 5 bolt turbine exhaust housing is its placement of the turbo from a particular manifold (Rev-Hard is a perfect example) for downpipe placement. From my experience, its the removal of the 5th bolt is the PITA that makes it a determining factor. So for example, Inline Pro makes their SS manifolds specifically for both 4 bolt exhaust housings and 5 bolts separately. this is for downpipe placement as well as positioning for the turbo on the manifold.
I have always used 4 bolt housings because of the ease of removal, and the less amount of material for the manifold to deal with.
the 4 bolt is "better" than the 5 bolt, because there is no "wastegate hole" to cause any disruptions in the exhaust gas flow.</TD></TR></TABLE>
It doesn't matter for the wastegate hole because if you're using a weld flange for the 5 bolt, it will completely seal that hole regardless.
The only advantage of the 5 bolt turbine exhaust housing is its placement of the turbo from a particular manifold (Rev-Hard is a perfect example) for downpipe placement. From my experience, its the removal of the 5th bolt is the PITA that makes it a determining factor. So for example, Inline Pro makes their SS manifolds specifically for both 4 bolt exhaust housings and 5 bolts separately. this is for downpipe placement as well as positioning for the turbo on the manifold.
I have always used 4 bolt housings because of the ease of removal, and the less amount of material for the manifold to deal with.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by TheShodan »</TD></TR><TR><TD CLASS="quote">
It doesn't matter for the wastegate hole because if you're using a weld flange for the 5 bolt, it will completely seal that hole regardless.
.</TD></TR></TABLE>
but the "hole" will be there and still disrupt flow, the 4 bolt is a smoother housing.
It doesn't matter for the wastegate hole because if you're using a weld flange for the 5 bolt, it will completely seal that hole regardless.
.</TD></TR></TABLE>
but the "hole" will be there and still disrupt flow, the 4 bolt is a smoother housing.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Dturbocivic »</TD></TR><TR><TD CLASS="quote">
but the "hole" will be there and still disrupt flow, the 4 bolt is a smoother housing.</TD></TR></TABLE>
Its quite negligeble thermodynamically speaking, really...
but the "hole" will be there and still disrupt flow, the 4 bolt is a smoother housing.</TD></TR></TABLE>
Its quite negligeble thermodynamically speaking, really...
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<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by TheShodan »</TD></TR><TR><TD CLASS="quote">
Its quite negligeble thermodynamically speaking, really...</TD></TR></TABLE>
understandable....
i just like arguing on H-t
j/k
Its quite negligeble thermodynamically speaking, really...</TD></TR></TABLE>
understandable....
i just like arguing on H-t
j/k
I was wondering this too.. especially after reading this on ATPturbo
" The GT30R turbine housings with 4 bolt exit are made out of ductile Ni-Resist iron (has a nickel content of about 38%). This material is much better at withstanding high exhaust gas temperatures than regular cast iron. "
" The GT30R turbine housings with 4 bolt exit are made out of ductile Ni-Resist iron (has a nickel content of about 38%). This material is much better at withstanding high exhaust gas temperatures than regular cast iron. "
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by BlackT5 »</TD></TR><TR><TD CLASS="quote">I was wondering this too.. especially after reading this on ATPturbo
" The GT30R turbine housings with 4 bolt exit are made out of ductile Ni-Resist iron (has a nickel content of about 38%). This material is much better at withstanding high exhaust gas temperatures than regular cast iron. "</TD></TR></TABLE>
But that is just the metalurgy of the housing itself, not on the 4 bolt design. Ni-Resistant Iron and Carbon steel are both good materials to use other than Cast iron, but is not always available on the specific turbos.
" The GT30R turbine housings with 4 bolt exit are made out of ductile Ni-Resist iron (has a nickel content of about 38%). This material is much better at withstanding high exhaust gas temperatures than regular cast iron. "</TD></TR></TABLE>
But that is just the metalurgy of the housing itself, not on the 4 bolt design. Ni-Resistant Iron and Carbon steel are both good materials to use other than Cast iron, but is not always available on the specific turbos.
simply put,
5bolt = on center
4bolt = tangential
the 4bolt housing actually allows the exhaust gas to meet the inducer of the turbine much sooner than the 5bolt.
the 5bolt entry is almost on top of the shaft...
and yes, for arguements sake, the wastegate port on the volute of the 5bolt can cause a bit of turbulance.
hth
edit: as mac said though, due to some manifold placements, the 5bolt is the only option. this is the only reason we still offer a 5bolt option.
5bolt = on center
4bolt = tangential
the 4bolt housing actually allows the exhaust gas to meet the inducer of the turbine much sooner than the 5bolt.
the 5bolt entry is almost on top of the shaft...
and yes, for arguements sake, the wastegate port on the volute of the 5bolt can cause a bit of turbulance.
hth
edit: as mac said though, due to some manifold placements, the 5bolt is the only option. this is the only reason we still offer a 5bolt option.
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