So can you fill us in on what Garrett has said on your findings?

On another note I agree what others have said, this was open market for buying the turbo with nothing being said about needing more testing. But seems like no one is getting good results? Not even decent results..... I hope a rep from Garrett can chime in

I am just very curious because I almost went ahead with the purchase of this turbo, but I would be furious by now.....

 

Compared to stock it is a lag monster, about 1000 RPM's worse from my testing, hopefully it gains enough up top to counter that.

I'm getting compressor surge at part throttle 5psi while letting off slightly in 2nd-5th gear.

I also got compressor surge at WOT in 5th gear where as soon as my boost climbed past 20 psi at 3600-3800 rpm's you could hear a quick choo choo choo then it was fine at 4k+.

4th gear Spool Test, WOT at 2k and let off when it hits 20 PSI
Stock Turbo = 2800 stock Mivec, 2550 tuned Mivec
GT30 = 3600 tuned Mivec (although it might need more tweaking to enhance spool assuming it doesn't induce compressor surge)

My grams/second numbers do seem to be inflated (Doubled?) so it's possible that EvoScan has the wrong formula to make them read right. They do seem to be consistant though so it might just be a matter of reducing them by a certain percentage to get them to read correctly. Temps were still around 80F when I ran this log and previous Stock turbo log was done at 65F and that effects it as well. Here is a clean run with higher boost and no knock:

3rd gear pulls
- GT30 @ 23 psi @ 4000 tapering to 22 psi by 7000
- Stock Turbo @ 26 psi from 3500 to 5500 then tapers to 20 psi by 7000
RPM---GT30 Airflow--Stock Airflow
3500 ------ 281 ---------- 468
3750 ------ 375 ---------- 462
4000 ------ 456 ---------- 488
4250 ------ 487 ---------- 513
4500 ------ 525 ---------- 525
4750 ------ 537 ---------- 544
5000 ------ 556 ---------- 569
5250 ------ 581 ---------- 594
5500 ------ 619 ---------- 613
5750 ------ 631 ---------- 625
6000 ------ 650 ---------- 638
6250 ------ 669 ---------- 644
6500 ------ 700 ---------- 656
6750 ------ 725 ---------- 669
7000 ------ 756 ---------- 669
7250 ------ 781 ---------- -
7250 ------ 809 ---------- -


I am also logging knock and besides a few trickles of 1-2 knock counts as boost comes on and past 6500 the logs are free of any moderate or worse knock. My tune is basically the same as with my stock turbo so the higher flow sections are likely a bit rich once the turbo outflows the stocker. I'll know more once I have AFR's logged hopefully tomorrow night. I tried to tune out the trickle knock I got on the stock turbo and it was no use. I even dropped in 100 octane fuel to test the theory and there was still an occasional tickle at 6500 no matter what I did with increasing fuel or reducing timing.

Deatschwerks 800cc injectors, EvoScan claims 87% duty cycle already but I think that calculation was about 10% higher than it should be from what I've read. I'll talk with the EvoScan Guru's and find out if we can correct those numbers.

I'm hoping it's something that simple or one of the flow limit tables getting mad. If there was a boost leak that would explain me triggering it earlier than expected. Between the boost leak test and wideband I should have more ammo to fire at the issue.

I really do wish they tested this more before releasing it because swapping the turbo out is not an easy task on these Evo X's.

 

So... it flowed 47lbs/min vs. the stock 40lbs/min and made less power? Possible explaination?

 

Let me know when you figure it out.

Of course, one bad apple does not make a bad tree. I'd like to see another come through the shop at some point to totally make up my mind.

- bryan

 

Yeah that is confusing me, has anyone tested turbo outlet temps with a stock turbo at 20 psi versus the GT30 at the same 20 psi? Maybe a permanent boost leak in the compressor side or some kind of design flaw that is causing the air to overheat so it flows more but with hotter air and worse power?

 

It's quite possible that EvoScan just needs to be divided by 2. It is just a formula. In this case, you were flowing about 335g/s with the stock turbo which is in the same ballpark as the other guys, and the Garrett is flowing 405g/s or about 53lbs/min.

To eliminate one possible issue with the surge, have you tried the stock BOV? I just find it odd that you got it on the stock turbo too.

 

Hold your head high if you do find out it sucks..... you have will be able to do the swap in a fraction of the time now that yu have done it once! and you have a handful of kick *** parts to strap to a quality turbo. (knock on wood...i still hope the Gt30 works, i had high hopes )

 

Yeah I think I found a formula where 1 lbs/min = 7.5598 G/s @ 70 F so my readings may be about twice as high.

I've still got my stock BOV and will test to see if I get the same surge behaviour this weekend. Likely I'm just at the spool limits this laggy turbo will tolerate even with the anti-surge ported compressor housing.

 

I thought that too at first but 335 g/s is 44 lb/min

http://www.translatorscafe.com/cafe/...ond-%5Bg/s%5D/

either way the Evoscan formula is incorrect, which is ok, it's still in beta.

 

I remember when the X first came out, someone measured the outlet temps on the stock turbo and I want to say they got into the 400F range! It was waaaaay higher than expected. I guess part of sitting in the oven of the back of the engine bay.

 

yeah beta is beta. :P

I think the OBD2 datalogs I have were around 38 lb/min according to this:
https://www.evolutionm.net/forums/ev...ock-turbo.html

Once you hit 5500 RPM's that turbo was maxxed at that lb/min flow rate, the GT30 certainly seems to have longer legs up top, we will see.

 

I've logged up to 41 lb/min on the stocker

btw kudos on all the data you share.

 

Yeah it would be easier the second time around I'm sure. The car sounds completely different, less drone in the cabin but a little buzzier with the wrapped headers and O2 DP. What I like better is the turbo spoolup sound which is like an airplane compared to the stock turbo. The speed it was gaining on the highway at 23 psi tapering to 22 psi give me some hope... assuming I can make it work at 26 psi on pump gas.

Yeah I think it was Perrin that did that testing but with this 85-90F air we have had here lately the underhood temps are just crazy. This is with the DEI heat wrap and I can't even begin to imagine what it would be like without that stuff. I'm going to liberally apply that cool tape to any lines, wires, and piping that are in line of sight of the headers wrapped or not!

 

I figure the more data the better off we all are. Time to get some rest, tomorrow is another day.

 

I don't have a compressor surge on my 3071, neither I had it on the stock turbo. My boost is controlled by ECU though, I don't have a boost controller.