AMS EVO X O2 Housing / Eliminator with Comparison Pics!
BECAUSE it is cast, it'd be difficult to cast in a separator. Plus, I'm not sure how much of a benefit it'd be for the reason that the flow out of the turbine wheel has its own flowpath of about 2-3" before it gets to the elbow anyways.
When WORKS came out with their cast O2 housing for the Evo 8/9, some folks believed it actually performed worse than the OEM unit. WORKS insisted it was better, but they also said you needed to increase the boost to make it perform up to potential. Not saying this is the case with the AMS one.
If those folks used anything but a 3" inlet on the downpipe (76mm), then I could see how they would get worse performance as they'd go from a big hole into a small hole with a step change causing a flow resistance. Considering the number of 70mm, or 2.75" downpipes on the market, especially from the Japanese companies, it woud not surprise me if they created a bad mismatch of parts.
I think 'those folks' either didn't have a proper setup or just don't know what they're talking about. The main benefit of the Works was the actual 3" outlet of the elbow as opposed to the stock size of 2 3/8" IIRC. The stock might even be smaller.
If those folks used anything but a 3" inlet on the downpipe (76mm), then I could see how they would get worse performance as they'd go from a big hole into a small hole with a step change causing a flow resistance. Considering the number of 70mm, or 2.75" downpipes on the market, especially from the Japanese companies, it woud not surprise me if they created a bad mismatch of parts.
If those folks used anything but a 3" inlet on the downpipe (76mm), then I could see how they would get worse performance as they'd go from a big hole into a small hole with a step change causing a flow resistance. Considering the number of 70mm, or 2.75" downpipes on the market, especially from the Japanese companies, it woud not surprise me if they created a bad mismatch of parts.
The benefit is ALOT MORE than without one .. it doesn't matter if it's smooth and contoured .. flow turbulence is flow turbulence .. the further downstream you separate the 2 flows, the better and faster the flow ..
Unless you have CFD software .. its probably difficult to visualise ..
Merry christmas guys ..
It would also be a more expensive casting though 
Pretty much every step for casting it would get more complicated; molds, core boxes, etc etc. Added material cost too.
In this particular case, the flow from the turbine wheel has a clean path straight out of the wheel with no distrubtion from the wastegate flow, for a good 2-3 inches.
If you were go separate the flows and merge them further down as is generally considered 'ideal', I'd estimate that the main part of the power gain is not from preventing turbulence between the wastegate flow and turbine wheel flow as I think you're suggesting.
With the stock elbow, the flow from the turbine wheel gets dumped into a large volume chamber. So you'll get a pressure drop as the flow slows down at the step change from small area to BIG area. And the fact it's a big step change as opposed to a nice diffuser means even greater pressure drop. Then, it has to accelerate back up to a higher speed because of the small area of the discharge from the elbow.
Well, that's my best estimation at least. Merry Xmas everyone!
Pretty much every step for casting it would get more complicated; molds, core boxes, etc etc. Added material cost too.In this particular case, the flow from the turbine wheel has a clean path straight out of the wheel with no distrubtion from the wastegate flow, for a good 2-3 inches.
If you were go separate the flows and merge them further down as is generally considered 'ideal', I'd estimate that the main part of the power gain is not from preventing turbulence between the wastegate flow and turbine wheel flow as I think you're suggesting.
With the stock elbow, the flow from the turbine wheel gets dumped into a large volume chamber. So you'll get a pressure drop as the flow slows down at the step change from small area to BIG area. And the fact it's a big step change as opposed to a nice diffuser means even greater pressure drop. Then, it has to accelerate back up to a higher speed because of the small area of the discharge from the elbow.
Well, that's my best estimation at least. Merry Xmas everyone!
We are very close guys! Here is our first sample cast section welded to a flex pipe. Obviously this is not complete but the cast looks really good and will really help with reliability and heat transfer. Also you will notice the holes in the unit for a heat shield we will be incorporating with it
And finally aftermarket guys, making heat shield for they exhaust product.
It would also be a more expensive casting though Pretty much every step for casting it would get more complicated; molds, core boxes, etc etc. Added material cost too.
In this particular case, the flow from the turbine wheel has a clean path straight out of the wheel with no distrubtion from the wastegate flow, for a good 2-3 inches.
If you were go separate the flows and merge them further down as is generally considered 'ideal', I'd estimate that the main part of the power gain is not from preventing turbulence between the wastegate flow and turbine wheel flow as I think you're suggesting.
With the stock elbow, the flow from the turbine wheel gets dumped into a large volume chamber. So you'll get a pressure drop as the flow slows down at the step change from small area to BIG area. And the fact it's a big step change as opposed to a nice diffuser means even greater pressure drop. Then, it has to accelerate back up to a higher speed because of the small area of the discharge from the elbow.
Well, that's my best estimation at least. Merry Xmas everyone!
Pretty much every step for casting it would get more complicated; molds, core boxes, etc etc. Added material cost too.In this particular case, the flow from the turbine wheel has a clean path straight out of the wheel with no distrubtion from the wastegate flow, for a good 2-3 inches.
If you were go separate the flows and merge them further down as is generally considered 'ideal', I'd estimate that the main part of the power gain is not from preventing turbulence between the wastegate flow and turbine wheel flow as I think you're suggesting.
With the stock elbow, the flow from the turbine wheel gets dumped into a large volume chamber. So you'll get a pressure drop as the flow slows down at the step change from small area to BIG area. And the fact it's a big step change as opposed to a nice diffuser means even greater pressure drop. Then, it has to accelerate back up to a higher speed because of the small area of the discharge from the elbow.
Well, that's my best estimation at least. Merry Xmas everyone!
The straight path flow is visual .. fluid flow is different
Actually for the last para, you got it wrong way round .. you WANT pressure drop ..the turbine spins primarily based on pressure differential .. the higher the differential the better your turbine spools .. what happens when you have turbulent exit is they become a bottleneck .. and the pressure increases at the exit end .. slowing down the turbine speed .. that is the reason for the elbow .. reduce turbulence, increased area and increase turbine response
My point on asking in case I miss it is .. if you want to do it ..then do it right
Maybe AMS found something different .. or its a compromise for a heatshield
I blame it on the egg nog!
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Rich was kind enough to take some more pictures to give you guys a good idea of what this piece is like compared to stock. First is a picture of the turbine housing on the stock turbo to give you an idea of how it bolts up. Next are a couple of comparison pics
Lastly a very scientific comparison pic of how far I can shove my arm into each.
Lastly a very scientific comparison pic of how far I can shove my arm into each.
Thread Starter
Former Sponsor
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From: West Chicago, IL
yeah, damn thing wont come off. I have tried just about everything short of burning it off LOL. The other one is just as bad too. Must me some rare string of rash or something.
No prices just yet. we really hate to release things until they can actually leave the door. All of us that work here at one point in our lives were customers just like you and we know how much it sucks to pay for something and have to wait and wait and wait for it. This is why we won't actually release pricing and sell them until we have a solid and SHORT lead time for them. Casting takes a while but we are turning things around pretty quickly now. I would say a pessimistic goal would be mid to late February but it could be sooner. This piece is super high quality and worth the wait guys. We designed it to fit like OEM and when incorporated with the heat shield to look like stock for you CA guys that are trying to fly under the radar.
Eric
No prices just yet. we really hate to release things until they can actually leave the door. All of us that work here at one point in our lives were customers just like you and we know how much it sucks to pay for something and have to wait and wait and wait for it. This is why we won't actually release pricing and sell them until we have a solid and SHORT lead time for them. Casting takes a while but we are turning things around pretty quickly now. I would say a pessimistic goal would be mid to late February but it could be sooner. This piece is super high quality and worth the wait guys. We designed it to fit like OEM and when incorporated with the heat shield to look like stock for you CA guys that are trying to fly under the radar.
Eric