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As far as I know, most of the 'enhancements' are compressor housing upgrades and new turbine housings. Will be nice to see some back-to-back comparisons to see what this adds up to.
 

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That's easy to do, you could make a 'bolt-in' OEM location for the Subaru too, just get the ATP compressor inlet and turbine housing. In that pic you can see they are doing the same thing, using an IHI compressor housing.

I guess the point I'm trying to make is that OEM housings already exist, since they are 30/35R CHRA and GTX wheels.
 

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How is a 2867R gen 2 making 550hp when the compressor map stops at 48lb/mn? The wheel is smaller then a 2871. ( I don't know that much about garret turbos and am just learning how read compressor maps.)
 

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How is a 2867R gen 2 making 550hp when the compressor map stops at 48lb/mn? The wheel is smaller then a 2871. ( I don't know that much about garret turbos and am just learning how read compressor maps.)

I don't understand how the 2867 is going to make that much power either. If it can really make that kind of power it could be the turbo to own on these cars. 10hp less than the 3071???
 

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I don't understand how the 2867 is going to make that much power either. If it can really make that kind of power it could be the turbo to own on these cars. 10hp less than the 3071???
Same for the new rated power outputs for the 3071 or the 3076. These turbos mustve been wrung out to the max. They were very generous with these numbers. If what they claim is true of a 3071 gen 2 being 10% to 20% more efficient across the board the pressure ratio using the ej257 motors, then my local dyno will see 520+whp on e85. So its on par with the gtx3076r gen 1.
 

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Same for the new rated power outputs for the 3071 or the 3076. These turbos mustve been wrung out to the max. They were very generous with these numbers. If what they claim is true of a 3071 gen 2 being 10% to 20% more efficient across the board the pressure ratio using the ej257 motors, then my local dyno will see 520+whp on e85. So its on par with the gtx3076r gen 1.
What's odd is the, "horsepower increase" numbers don't seem to really make sense. The GTX3071R rating is not all that improved from what we have seen with the gen 1. From what I have seen, the gen 1 GTX3071 is right on par in terms of output with the old GT3076 (what I run). No way was the 1st gen GTX3071R maxing out at only 450hp, maybe on 91. It was already a 57 lb/min turbo. I've seen them making upwards of 425whp on a dyno dynamics that reads 215whp for stock cars.


What's really, really odd is they're saying that both the GTX3076R and GTX3576R top out at 750hp, but that to get to that figure the gen 2 GTX3076R picked up 110hp while the GTX3576R picked up 150hp. . . so they're mathematically saying the first gen GTX3076R could put down 40 more horsepower than the first gen GTX3576R. . . what?

I'm thinking there are some mistakes in this article. It just doesn't seem to add up.
 

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What's odd is the, "horsepower increase" numbers don't seem to really make sense. The GTX3071R rating is not all that improved from what we have seen with the gen 1. From what I have seen, the gen 1 GTX3071 is right on par in terms of output with the old GT3076 (what I run). No way was the 1st gen GTX3071R maxing out at only 450hp, maybe on 91. It was already a 57 lb/min turbo. I've seen them making upwards of 425whp on a dyno dynamics that reads 215whp for stock cars.


What's really, really odd is they're saying that both the GTX3076R and GTX3576R top out at 750hp, but that to get to that figure the gen 2 GTX3076R picked up 110hp while the GTX3576R picked up 150hp. . . so they're mathematically saying the first gen GTX3076R could put down 40 more horsepower than the first gen GTX3576R. . . what?

I'm thinking there are some mistakes in this article. It just doesn't seem to add up.
I was just about to post up the map for the gen 2 3576 and 3076. Was about to say the same thing. Someones testing variable was not set up right or something was recorded wrong. I dont see a smaller turbine wheel and same size compressor of 76mm will make more up top on the same ar hotside with the flow of the ej motor and heads.
 

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They are based on compressor maps, and since they both use the same compressor wheels, they can flow the same amount of air. A turbo has two wheels and this only tells half the story.

IMO there's no reason to use a 3076 on these engines (bore/stroke, design, etc.). These engines have been shown time and time again to provide a MUCH better and usable power curve with a bigger hotside. Case in point the 3076 and 3576 spool within a couple hundred RPMs of each other, but the 3576 make +150 more WHP, and has the potential to carry the power much further into the revs. This is all due to the reduced backpressure the much freer flowing 35R turbine housing provides.
 

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Thanks for explaining the comparison :)
 

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They are based on compressor maps, and since they both use the same compressor wheels, they can flow the same amount of air. A turbo has two wheels and this only tells half the story.

IMO there's no reason to use a 3076 on these engines (bore/stroke, design, etc.). These engines have been shown time and time again to provide a MUCH better and usable power curve with a bigger hotside. Case in point the 3076 and 3576 spool within a couple hundred RPMs of each other, but the 3576 make +150 more WHP, and has the potential to carry the power much further into the revs. This is all due to the reduced backpressure the much freer flowing 35R turbine housing provides.
That actually doesn't explain the confusion whatsoever.

Again, the table states both are capable of a max of 750hp, but to get to that same 750, the GTX3576R picked up 150hp while the GTX3076R picked up 110hp. They are inherently stating that the max output of the Gen 1 GTX3076R and GTX3576R were 640hp and 600hp respectively, meaning the GTX3076R was capable of 40hp more than the GTX3576R. That does not add up.
 

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You're only looking at the compressor maps. It's half the story.
...so did the first gen GTX3076R and GTX3576R not have the same compressor wheel? Because if these ratings are based purely on max flow than both turbos should have had the same rating for Gen 1 as well. Instead they are saying the first gen GTX3076R had a higher peak flow than the first gen GTX3576R which, again, doesn't make sense if it's based purely on the compressor and they were the same before too.
 
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