Guys, let me try to understand.

GTX3576R has a bigger compressor wheel than the GTX3076R. The GTX3076R can't exhaust the air fast enough compared to the GTX3576R. Is it because the GTX3576R has a bigger exducer wheel/hotside?

 

http://www.enginebasics.com/Advanced...0GTX3576R.html

 

On Garrett the first two numbers represent the turbine wheel. The second two are the diameter of the compressor wheel. So a GTX3071R has a gt30 turbine wheel with a 71mm compressor wheel ball bearing because of the R designation and billet compressor due to X. A GTX3571R is the same except a 35 turbine wheel. A standard GT35R is a GT3582R. A billet is GTX3582R. The 71 and 76mm compressor wheels were previously considered too small for the 35 turbine wheel. Now the billet versions flow more so they are a better match.

I think options E D and B are the only 3 I would consider. E if it is free or low cost. D if you need a new turbo because the cost is lower than B and will help a lot towards efficiency. Option B is the most expensive but it offers a wide variety of options to make power. I have a 2.4 with a 6262 and it is very responsive in the 4k+ range.

I would say for your power goals though a Green would easily do it in the new turbine housing. The loss of the stock housing and internal gate will be huge. It also has the same turbine wheel now as red and black.

 

As much as i'd love to believe the theory of the 3576 hype i've not seen one dynograph that makes me want to ditch my 3076 for it.

 

No. the blade design and inducer exducer sizes are completely different.

I'll show you an example here.

Standard GT3076R is on the left, GTX3076R is on the right




But notice, the exhaust wheel is still the same N111 60mm 84 trim turbine wheel


The difference in blade designs are very obvious. the GT3076R and other upgrades (GT3076HTA, TR3030R, etc) use a 6 or 7 splitter blade design, while the GTX uses an older 11 single-blade design with a curved backwall and slightly extended tip.



Here's a more exposed look at the GTX3076R





On the test units I've used, the actual comparison of the GTX3076R vs. the GT3076R is different in actual use than on paper. Mainly because of the fact that the compressor wheel is a bit too much for the N111 exhaust wheel. It doesn't show the same efficiency improvements that I experienced with the comparison between the GT3071R and the GTX3071R. (which was about 15-18% from 1.9-2.5PR on about 3 platforms that i worked with). Response was decent but midrange power dropped, while top end was extended quite high. but it overwhelmed the turbine wheel even with a larger 1.06 turbine housing. this is why that GTX3576R was made. This wasn't just "dyno" comparisons, this was actually driving several cars that originally had a GT3076R and converted to a GTX3076R.

That's quite on par with that link that Pure Evo IX had IMHO from its use so far.

 

That's because users of them are going for a bit more top end than the GTX3076R user. Its for those trying to go for the 600AWHP setup that don't want to stretch the usability of the 60mm exhaust wheel. Even the GT3076RHTA had a better range of torque for 2.0 litre and below from 2200-7000rpms. A "dyno" is only a snapshot in 4th gear. there's no WAY to give an accurate comparison online without just using one. Call me a person that's just not a dyno ****.

I recently picked one up as a unit to work with someone's 2.0 litre 4G63 at a shop. He originally had a 62mm variant and wanted more usable power for his 500AWHP E85 goals and was surprised at the results. I'll see if the shop still has a dyno with boost/rpm data available.




I really thought the 68mm N32 move was a better idea for his goals with E85.

 

I have come across three different people who tried both the gtx3076 and gtx3576. they all raved about how well the gtx3576 worked.

I have a fair amount of experience with 3076 turbos. my take is the gt30 turbine wheel is very "exhaust housing fussy" it simply performs really bad in some exhaust housings. get it in the correct exhaust housing and the turbine wheel can support 550-600whp with fast spool. a well setup gt3076 (no gtx) does not benefit from the larger 35 turbine wheel. the gtx3076 is compressor wheel capable of 100whp more than a standard 3076. thats when the bigger turbine is really needed.

 

On a 3076 .63 i am already hitting 547 so i'm thinking t4 ts .82 housing with a 3.5 downpipe. Guess i'll have to wait tho till they do a ni resist in t4.

 

Grimgrak, on that same dyno, how much would a bone stock evo make? Just trying to do ricer math and do a correction factor to my local dyno. lol.

 

English Racing Dynojet.
I was curious about the gtx3576 when it first came out more than a year ago.
Yet if it worked so well i'm sure there would be mountains of dynosheets flowing in to show how it kicks gt30 butt.
Until I see this I will continue to maximize gains on my gt3076

 

Thanks for the detailed photos and explanation. I was actually curious about whether the turbine blade design was the same for the GT30 and GTX30, but you covered the turbine and compressor which is even better. Interesting that the GTX uses an "older" compressor wheel blade design. Normally, older implies lower performance, but not in this case? Or were there changes to the design that made the older style layout work better than the splitter style?

Do you have any profile pics of the turbine wheel?

 

Zhong
Subract 12% from ER dyno figures, and you'll be in the ball-park of FFTec MD: 500whp at ER is ~440whp at FFTec.
Close enough for comparison.
IF GTX3576R makes 600whp at ER, than its maybe 520whp at FFTec. Subtract another 50whp for "safe track tune", and you are at 470whp.

 

nice ricer math. lol.

 

Zhong, do you still have a HP limit in the class you're running?

 

No limit. I want RELIABLE, SAFE, CONSERVATIVE power/torque in constant high stress/high heat/high load conditions. Maybe even tune with the hood closed too.