He's paying for R&D and I ain't...
That's $1500 to cheer about!

 

Hopefully the numbers will add up, ripping the turbo out again would not be one of my favorite things to do at this point. On one hand I'm glad I saved $600-$800 in labor but the hours it took out of the schedule as well as the torture my battered body is enduring say otherwise.

I'll have to contact Garrett and see if they want to send me that $1500 check for testing their turbo.

 

we have tested ours... and are still testing..

stock o2 housing (which i view as a restriction)... stock downpipe to our resonated and dual muffler catback... cbrd intake.... cbrd vertical fmic..... DW 800cc injectors

26.7 psi we saw 357whp 298wtq in 80 degree heat with I believe 40% humidity.... the car on the stock turbo was in the 320-328whp range, with torque around 310-315...

we are seeing ABOUT a 40whp jump up top past 4995 to redline, but losing 90wtq at 3800 rpm....

im going to do some experimenting with the WG actuator and boost pressures to see if the power goes up.

We are one of the official garrett test partners, and they have been very open to our findings.

cheers

cb

 

shouldn't all of this test partnering stuff have been done before the turbo is released?

 

Are you utilizing your weather station Chad?

It just occurred to me that your dyno is inside and probably air conditioned in there which might not make sense to have the weather station involved in the numbers.

Ack, I'm confused so let me know.

 

Seems like most are having issues with stock parts right before and after the turbo. Cams and/or headers pre turbo and O2 Downpipe after turbo may really be needed with this turbo to make it flow well. Possibly by having stock parts with huge .94 AR twin scroll exhaust housing followed by more stock parts might just not work well.

I got a few more logs in after dinner but won't be doing higher boost until tomorrow. The car feels great considering the lower boost setting anywhere past 4000 RPM's. I have a feeling that another 9 psi will wake up the mid range considerably and push the top end power quite a bit higher.

3rd gear pulls
- GT30 @ 17 psi from 4000 to 7000
- Stock Turbo @ 26 psi from 3500 to 5500 then tapers to 20 psi by 7000
RPM---GT30 Airflow--Stock Airflow
3500 ------ 225 ---------- 468
3750 ------ 294 ---------- 462
4000 ------ 381 ---------- 488
4250 ------ 375 ---------- 513
4500 ------ 394 ---------- 525
4750 ------ 425 ---------- 544
5000 ------ 450 ---------- 569
5250 ------ 481 ---------- 594
5500 ------ 506 ---------- 613
5750 ------ 519 ---------- 625
6000 ------ 544 ---------- 638
6250 ------ 569 ---------- 644
6500 ------ 606 ---------- 656
6750 ------ 619 ---------- 669
7000 ------ 662 ---------- 669

Of course the tune may be off for the bigger turbo by quite a margin running WOT at that low boost but it shows how opposite the power curve of these turbos are. The GT30 doesn't really come alive until 3750 and you get a part throttle surge effect under 3500 RPM's which didn't happen on the stock turbo past 2700.

For comparison the stock turbo would hit 20 psi or ~300 Airflow by 2900-3000 RPM's where as the GT30 hit that 300 Airflow at 3800 but was only set for 17 psi. I guess we'll see how the numbers shape up with higher boost shortly!

 

You did only a turbo swap between setups right?

With regards to your comment on the 'big' turbo with stock parts, it makes sense. Somewhat like using a tubular manifold with a stock turbo; you're not going to see a lot of peak gains if you already had the the turbo at the limit because the stock turbo is the major bottle neck.

Same difference as using a GT35 with a 1.5" exhaust; it just won't work well.

Judging by your last three data points, the stock turbo is maxed out whereas the 3076 has plenty of room to go, as you'd expect. Essentially same airflow (and I'd guess power) at 3psi less boost is a positive result and also what you'd expect with a bigger turbo.

 

Well, at least you know it was done right! I won't let anyone touch my car, not even for an oil change. Who knows if they torqued things properly, put on anti-seize, didn't get lazy and leave a bolt/nut or two off, etc.

 

I tried to limit what was was changed when I upgraded the turbo but I did install the ETS Manifold and UR o2 DP at the same time. Just those parts should have netted me around 30 whp assuming they were a flow restriction before. I'm hopefull as I turn up the boost it will fly, only difference was it was 20F warmer out than the previous logs I compared which is significant. The upper intercooler pipe seemed to be hotter than I ever remember it, I wish I had a temp log of that before and after to compare.

 

I've already removed my 30R and installed a Dom2...just waiting to tune it now. At least the surging is gone now!

 

^^ So far, the dom 2 already feels better?

 

Night and day, with the Garrett in the car would surge in every gear and was almost undrivable. With the Dom2 (untuned) it feels like a normal car again.

 

nice! you have a tune date set-up yet?

 

Which made me think it was an install error, most likely the inlet elbow, HiBoost is not having that issue.

 

I'm curious about the 'part throttle' surge. That shouldn't even happen with the stock turbo. I wonder if the throttle tip-in enrichment is really rich, causing a slight misfire that would feel like surge.