New Red+Big A** Compressor housing=
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Joined: Mar 2008
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From: uk
is it actually an anti surge shroud it doesn't look functional in the pic!
excuse my quick sketch
in pic 1 the shroud is just larger than pic 2 so the opening to the inducer is the same which is how i see the new red is atm?
and pic 3 for true anti-surge air can enter and exit other than at the inducer.
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excuse my quick sketch
in pic 1 the shroud is just larger than pic 2 so the opening to the inducer is the same which is how i see the new red is atm?
and pic 3 for true anti-surge air can enter and exit other than at the inducer.
.
Last edited by leecavturbo; Apr 30, 2009 at 08:38 AM.
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From: Birmingham, AL
I don't quite understand your...ahem...technical diagram, but are you saying that it has to have surge ports to be an anti-surge shroud? The way I understood things is that just having more room in the compressor housing giving the wheel more volume to work with combats surge. ITs the same thing that happened when the first "white" rabbit and 20G comp wheel in a 16g housing combo turbos came out.
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Joined: Mar 2008
Posts: 1,392
Likes: 2
From: uk
I don't quite understand your...ahem...technical diagram, but are you saying that it has to have surge ports to be an anti-surge shroud? The way I understood things is that just having more room in the compressor housing giving the wheel more volume to work with combats surge. ITs the same thing that happened when the first "white" rabbit and 20G comp wheel in a 16g housing combo turbos came out.
if the inner snorkel feeding the inducer is enlargend or some scientific radius/venturi then i would say would help flow.
but just by having a secondary area i don't believe will do anything.
ONLY MY OPINION waits to be educated
more pics.
.
.
Last edited by leecavturbo; Apr 30, 2009 at 12:36 PM.
an anti-surge works by when the pressure is high but the turbine compressor speed is slow then surge ports relieve that over pressure (surge) is how i understood it to work.
if the inner snorkel feeding the inducer is enlargend or some scientific radius/venturi then i would say would help flow.
but just by having a secondary area i don't believe will do anything.
ONLY MY OPINION waits to be educated
more pics.
if the inner snorkel feeding the inducer is enlargend or some scientific radius/venturi then i would say would help flow.
but just by having a secondary area i don't believe will do anything.
ONLY MY OPINION waits to be educated
more pics.
Straight from Garrett's website ...
Ported Shroud compressor (see Fig. 2) is a feature that is incorporated into the compressor housing. It functions to move the surge line further to the left (see Fig. 3) by allowing some airflow to exit the wheel through the port to keep surge from occurring. This provides additional useable range and allows a larger compressor to be used for higher flow requirements without risking running the compressor into a dangerous surge condition. The presence of the ported shroud usually has a minor negative impact on compressor efficiency.
More usable range for a slight spool tradeoff.
Here is a picture of a new design turbo with HKS style anti-surge (like Red) and a bullet nut to secure compressor. The nut is supposed to help direct airflow and maybe give back a little of what anti-surge takes away. HKS claims 1-2% more efficient flow with bullet nut from their testing.
PS I hope to have this turbo on my car next week.
Ported Shroud compressor (see Fig. 2) is a feature that is incorporated into the compressor housing. It functions to move the surge line further to the left (see Fig. 3) by allowing some airflow to exit the wheel through the port to keep surge from occurring. This provides additional useable range and allows a larger compressor to be used for higher flow requirements without risking running the compressor into a dangerous surge condition. The presence of the ported shroud usually has a minor negative impact on compressor efficiency.
More usable range for a slight spool tradeoff.
Here is a picture of a new design turbo with HKS style anti-surge (like Red) and a bullet nut to secure compressor. The nut is supposed to help direct airflow and maybe give back a little of what anti-surge takes away. HKS claims 1-2% more efficient flow with bullet nut from their testing.
PS I hope to have this turbo on my car next week.
Last edited by oldevodude; May 31, 2009 at 01:03 AM.
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. I just sent my sending unit to Buschur for the double pumper, and should be getting there Monday. I'm also taking out the tru-boost in favor of ecu-controlled boost via JDM 3 Bar and 3 port solenoid. Those are the last things that need to be done (contemplating porting the intake mani and TB) before I get tuned. I will be on E85 most of the time. I can't wait to just have this build done already cause I have a feeling this car is going to be ridiculously fun!!
Mainly it gaines quite a bit of usable flow left of where the normal surge line is which would require the turbo to build boost quickly and at lower RPM's to even utilize. The slight negative impact they are referring to is moving the efficiency islands (red lines in graph) to the left including the choke line at max flow but it seems to be well worth the tradeoff for more usable range. I'm pretty sure there is no spool penalty associated with the ported shroud, not sure where you read that.
Here is a picture of a new design turbo with HKS style anti-surge (like Red) and a bullet nut to secure compressor. The nut is supposed to help direct airflow and maybe give back a little of what anti-surge takes away. HKS claims 1-2% more efficient flow with bullet nut
Last edited by Hiboost; May 31, 2009 at 07:18 AM.
Straight from Garrett's website ...
Ported Shroud compressor (see Fig. 2) is a feature that is incorporated into the compressor housing. It functions to move the surge line further to the left (see Fig. 3) by allowing some airflow to exit the wheel through the port to keep surge from occurring. This provides additional useable range and allows a larger compressor to be used for higher flow requirements without risking running the compressor into a dangerous surge condition. The presence of the ported shroud usually has a minor negative impact on compressor efficiency.
More usable range for a slight spool tradeoff.
Here is a picture of a new design turbo with HKS style anti-surge (like Red) and a bullet nut to secure compressor. The nut is supposed to help direct airflow and maybe give back a little of what anti-surge takes away. HKS claims 1-2% more efficient flow with bullet nut from their testing.
PS I hope to have this turbo on my car next week.
Ported Shroud compressor (see Fig. 2) is a feature that is incorporated into the compressor housing. It functions to move the surge line further to the left (see Fig. 3) by allowing some airflow to exit the wheel through the port to keep surge from occurring. This provides additional useable range and allows a larger compressor to be used for higher flow requirements without risking running the compressor into a dangerous surge condition. The presence of the ported shroud usually has a minor negative impact on compressor efficiency.
More usable range for a slight spool tradeoff.
Here is a picture of a new design turbo with HKS style anti-surge (like Red) and a bullet nut to secure compressor. The nut is supposed to help direct airflow and maybe give back a little of what anti-surge takes away. HKS claims 1-2% more efficient flow with bullet nut from their testing.
PS I hope to have this turbo on my car next week.
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Joined: Mar 2008
Posts: 1,392
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From: uk
Check out FP's website and look at the pictures they have up there. There are a few shots with more of an angle on the Anti-surge compressor housing and there are narrow slots just before the inducer that allow excess flow to exit the compressor blade area and loop around back to where the intake pipe attaches. It's setup the same way on my Garrett GT3076r so I think it should work fine that way.