GTX SHOWDOWN: GTX3076r vs GTX3576r
Mar 11, 2012, 02:33 PM
#16
Regarding the effect of the cat.
Here's a dyno chart on an Evo X going from the stock O2 housing and stock cat to a AMS widemouth and a test pipe.
It looks to be roughly 150pm difference in spool. Remember, this is going from the very restrictive stock O2 housing and cat to the free flowing AMS widemouth DP and a test pipe.
In the case of 240Z, he went from a high flow cat to the test pipe. I figure in this case, it's maybe a 50rpm difference in spool up between the high flow cat and test pipe. Maybe somewhere around 10-15whp difference in peak power. Hard to say as it depends on the cell count of the high flow cat, etc.
Looking at the two sets of graphs from 240Z, the GTX3576 make anywhere from 45-55whp more peak in combination with the test pipe. So the actual contribution from the turbo may be 35-45whp, give or take.
Here's a dyno chart on an Evo X going from the stock O2 housing and stock cat to a AMS widemouth and a test pipe.
It looks to be roughly 150pm difference in spool. Remember, this is going from the very restrictive stock O2 housing and cat to the free flowing AMS widemouth DP and a test pipe.
In the case of 240Z, he went from a high flow cat to the test pipe. I figure in this case, it's maybe a 50rpm difference in spool up between the high flow cat and test pipe. Maybe somewhere around 10-15whp difference in peak power. Hard to say as it depends on the cell count of the high flow cat, etc.
Looking at the two sets of graphs from 240Z, the GTX3576 make anywhere from 45-55whp more peak in combination with the test pipe. So the actual contribution from the turbo may be 35-45whp, give or take.
I know companies have done back to back tests on lower powered cars with HFC versus test pipes and the results looked great, Sadly that wasnt the case when i tested mine around 450WHP the results were terrible.
Mar 11, 2012, 07:45 PM
#17
You do make a valid point about turbo size. Horsepower is a function of airflow, so more power requires more airflow. With more airflow, the difference in backpressure between to different flow restrictions should increase. Though I would think it would affect peak power more than spoolup.
Mar 11, 2012, 07:55 PM
#18
Thanks for this bro! Im just gonna keep my GTX3076 and see what happens. I got the ATP version which CLAIMS 600HP :-/ They do get 500WHP on e85 but unknown amount of boost. on a evo 8 with 272 cams...
The intent of the thread is to report my findings in the context of the changes made for my setup.
Here are my thoughts between the two turbochargers based on the 1.06 A/R T4 TS turbine housing.
Spool: If you only change the turbo and all else remains equal you will likely not see a difference in spool. If I had to pick a winner it would be the GTX3076r.
Power w/ 3" exhaust and High Flow CAT: If you run a 3" exhaust with CAT and run 30psi of boost you will likely not see a significant benefit going to the GTX3576r. This is likely due to the CAT being the limiting factor
Power w/ 3" exhaust and no CAT: If you run a 3" exhaust and no CAT you will see a benefit of going to the GTX3576r if you are trying to exceed 475-500hp@wheels. The GTX3076r hits a wall around the 475-500hp@wheels due to the restrictions created by the smaller turbine wheel. It is not to say you can't make more power, but it will be much easier with the GTX3576r.
Summary: If I had to make a simple rule of thumb between the two turbochargers it would be the following....
<475@wheels GTX3076r
>475@wheels GTX3576r
Here are my thoughts between the two turbochargers based on the 1.06 A/R T4 TS turbine housing.
Spool: If you only change the turbo and all else remains equal you will likely not see a difference in spool. If I had to pick a winner it would be the GTX3076r.
Power w/ 3" exhaust and High Flow CAT: If you run a 3" exhaust with CAT and run 30psi of boost you will likely not see a significant benefit going to the GTX3576r. This is likely due to the CAT being the limiting factor
Power w/ 3" exhaust and no CAT: If you run a 3" exhaust and no CAT you will see a benefit of going to the GTX3576r if you are trying to exceed 475-500hp@wheels. The GTX3076r hits a wall around the 475-500hp@wheels due to the restrictions created by the smaller turbine wheel. It is not to say you can't make more power, but it will be much easier with the GTX3576r.
Summary: If I had to make a simple rule of thumb between the two turbochargers it would be the following....
<475@wheels GTX3076r
>475@wheels GTX3576r
Mar 11, 2012, 09:57 PM
#19
this is good info for sure , thanks for doing the test.
500 whp on a 3076 should be no problem, i did 498 on a stock 2.0 and a standard 3076. And then did 570whp same set up on a 2.4.
I like what ive been seeing with this GTX 3076 ,
would like to see someone really push it on a built motor to see what it really could do, similar to the test that DB did with the HTA 3076 he made 600/600 basiclly with his.
500 whp on a 3076 should be no problem, i did 498 on a stock 2.0 and a standard 3076. And then did 570whp same set up on a 2.4.
I like what ive been seeing with this GTX 3076 ,
would like to see someone really push it on a built motor to see what it really could do, similar to the test that DB did with the HTA 3076 he made 600/600 basiclly with his.
Mar 11, 2012, 10:14 PM
#20
this is good info for sure , thanks for doing the test.
500 whp on a 3076 should be no problem, i did 498 on a stock 2.0 and a standard 3076. And then did 570whp same set up on a 2.4.
I like what ive been seeing with this GTX 3076 ,
would like to see someone really push it on a built motor to see what it really could do, similar to the test that DB did with the HTA 3076 he made 600/600 basiclly with his.
500 whp on a 3076 should be no problem, i did 498 on a stock 2.0 and a standard 3076. And then did 570whp same set up on a 2.4.
I like what ive been seeing with this GTX 3076 ,
would like to see someone really push it on a built motor to see what it really could do, similar to the test that DB did with the HTA 3076 he made 600/600 basiclly with his.
Mar 12, 2012, 03:55 PM
#21
Thanks for the info.
To those worried about the cat and thinking its worth 400 RPM on spool, that might be the case on the stock cat, but the Mil-spec cat had no perceivable impact on power on my car at the 350WHP level. I imagine the effect during spool up would be negligible here, although it is an unknown.
Figure 20-25 HP for the difference in boost and the GT35 turbine seems to be worth about 20-25 WHP across the board with no noticeable impact on spool?
Wonder how they compare on kill mode. I'm curious if the GT30 can keep up to the compressor or if the GT35 will keep EBP low enough at the compressor limit to allow some extra airflow and more timing advance.
To those worried about the cat and thinking its worth 400 RPM on spool, that might be the case on the stock cat, but the Mil-spec cat had no perceivable impact on power on my car at the 350WHP level. I imagine the effect during spool up would be negligible here, although it is an unknown.
Figure 20-25 HP for the difference in boost and the GT35 turbine seems to be worth about 20-25 WHP across the board with no noticeable impact on spool?
Wonder how they compare on kill mode. I'm curious if the GT30 can keep up to the compressor or if the GT35 will keep EBP low enough at the compressor limit to allow some extra airflow and more timing advance.
Mar 13, 2012, 11:54 PM
#22
Love it. Continuing to shed light on the GTX line...I see serious potential in the 3576. Great results. There's gotta be some trade-off going from the 3076 to the 3576 tho...? The graphs seem to disagree but I'd like to hear some more driving impressions once you get to know the turbo a little better.
http://www.motoiq.com/magazine_artic...p-details.aspx
For sure, the 3576 has greater mass and rotational inertia, but it can be overcome by better turbine efficiency. From 240Z's testing, the 3576 looks to be the equal in spool-up, and better in power. The question comes in transient response behavior/boost recovery between shifts. Of course, there's also anti-lag for that
Last edited by spdracerut; Mar 13, 2012 at 11:58 PM.
Mar 14, 2012, 05:27 AM
#23
Thanks for the info.
To those worried about the cat and thinking its worth 400 RPM on spool, that might be the case on the stock cat, but the Mil-spec cat had no perceivable impact on power on my car at the 350WHP level. I imagine the effect during spool up would be negligible here, although it is an unknown.
Figure 20-25 HP for the difference in boost and the GT35 turbine seems to be worth about 20-25 WHP across the board with no noticeable impact on spool?
Wonder how they compare on kill mode. I'm curious if the GT30 can keep up to the compressor or if the GT35 will keep EBP low enough at the compressor limit to allow some extra airflow and more timing advance.
To those worried about the cat and thinking its worth 400 RPM on spool, that might be the case on the stock cat, but the Mil-spec cat had no perceivable impact on power on my car at the 350WHP level. I imagine the effect during spool up would be negligible here, although it is an unknown.
Figure 20-25 HP for the difference in boost and the GT35 turbine seems to be worth about 20-25 WHP across the board with no noticeable impact on spool?
Wonder how they compare on kill mode. I'm curious if the GT30 can keep up to the compressor or if the GT35 will keep EBP low enough at the compressor limit to allow some extra airflow and more timing advance.
Im going to bow out of this thread after this because it gets old repeating myself.
Even 100 cell cats are restrictive (they rob power and loose spool), as the power of the car goes up the cat get more and more restrictive.... As already stated My car made 200WHP 400RPMs different just slapping a cat on it. This was at 460WHP>440WHP And i didnt try to regain spool with a retune(Probably Couldve made it a little better) i just pulled that ***** off as soon as i could.
The 3576 will NOT outspool the 3076 Proven fact on other tests. In fact on average they loose 250RPM. This test shows an easy 100RPM increase But with another fairly major change affecting it. Can anyone figure out what that is ????
I sure wish i would swap out to a larger turbo and pick up power everywhere but that is simply not the case in the real world.
Mar 14, 2012, 07:11 AM
#25
Theres more to the flow difference between a cat and test pipe then just the diameter and design. My 3.5inch catco 100cell cat still doesn't flow as well as my 3inch test pipe. The difference is due to laminar flow vs turbulent flow and reynold's number.
As an added bonus with the better flow my test pipe is quieter than my cat. Yea its resonated, but still...unexpected!
As an added bonus with the better flow my test pipe is quieter than my cat. Yea its resonated, but still...unexpected!
Mar 14, 2012, 08:11 AM
#26
What other tests? Link? This is the ONLY test I've found in searching all of the internet. There's been a GTX3576 installed on a STI as posted on Iwsti board. I think also posted on the Facebook page of a tuner shop, but no dynos. There's a dyno video of a Mazdaspeed 6 in Austin at MZM, but no dyno chart.
Those are the only other installs I have found so far and neither have data, much less back-to-back on the same car/setup data.
I would argue that 240Z has in fact shown the GTX3576 will spool up the same as a GTX3076. A regular GT3076 will spool up a little sooner.
Those are the only other installs I have found so far and neither have data, much less back-to-back on the same car/setup data.
I would argue that 240Z has in fact shown the GTX3576 will spool up the same as a GTX3076. A regular GT3076 will spool up a little sooner.
Mar 14, 2012, 08:22 AM
#27
For sure, the 3576 has greater mass and rotational inertia, but it can be overcome by better turbine efficiency. From 240Z's testing, the 3576 looks to be the equal in spool-up, and better in power. The question comes in transient response behavior/boost recovery between shifts. Of course, there's also anti-lag for that
Mar 14, 2012, 09:56 AM
#28
I don't think it is a question of being crappy, but choosing a turbo that is suitable for the application and the desire power you seek. There have been several members that have achieved 600whp with the GT30r turbine wheel, but I would argue that if you seek to exceed 475@wheels you should consider going to the larger GT35r turbine wheel. Keep in mind that Curt also changed my MIVEC map so that contributed to the response after the turbo swap.