Welcome to the North American Subaru Impreza Owners Club Wednesday October 28, 2020
Home Forums Images WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Go Back   NASIOC > NASIOC Technical > Built Motor Discussion

Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!
Welcome to the NASIOC.com Subaru forum.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, free of charge, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.







* As an Amazon Associate I earn from qualifying purchases. 
* Registered users of the site do not see these ads. 
Reply
 
Thread Tools Display Modes
Old 10-06-2020, 03:21 AM   #51
beemba
Scooby Newbie
 
Member#: 483513
Join Date: Mar 2018
Chapter/Region: International
Location: UAE
Vehicle:
2015 WRX STI
Blue

Default

Quote:
Originally Posted by wuuusaa View Post
Yea that's Ibrahim's car, super cool dude. The G30-770 just wasn't reaching his power goals lol. He's since upgraded to a G30-900.

Here's another video of inside the car, you can see it's takes off around 3900 rpms and pull to redline. I would like to that turbo on E85 https://www.youtube.com/watch?v=jDBiHmLPF5U

Another video of them on GR STi
https://www.youtube.com/watch?v=AQz0DzXm5-w
Thank you Ibrahim here, this is actually Zuhair's car which still retains the G30-770.
* Registered users of the site do not see these ads.
beemba is offline   Reply With Quote
Sponsored Links
* Registered users of the site do not see these ads.
Old 10-06-2020, 03:29 AM   #52
beemba
Scooby Newbie
 
Member#: 483513
Join Date: Mar 2018
Chapter/Region: International
Location: UAE
Vehicle:
2015 WRX STI
Blue

Default

Just an update on my ride, reading through the last few pages of posts here, let me chime in with my personal experience on not one, but two Garrett G35-900 turbos i have been through. The first failed at ~1260 mi. the second failed at ~1430 mi.

The nature of failure was very gradual, with a faint, low frequency "Police siren" or "wooooo" noise accompanying spool, that gradually got louder to the point where the compressor inducer was seen to make contact with the compressor housing, and the shaft was seen to have axial runout when rotated.

Oil feed lines on both were brand new. No oiling issues, as all Oil parameters are monitored. No coolant supply problems either.

Tune was carried out by the most respected JDM Builder and tuner here in Dubai, and happens to receive, build and tune vehicles from all over the middle east and north Africa.

The first turbo was sent to Garrett for inspection, and they responded with the following:



880695-5001S

Analysis Findings : Rotor damage - Overspeed -
Technician Conclusion: Turbocharger returned with rubbing wheels vs. contours. Damage of compressor piston rings and overheated of ball bearing as a consequence of Turbo overspeed. During overspeeding cycles, the excessive growth of the compressor wheel may cause a permanent deformation (growth) of the central bore of the wheel, which forms into a barrel shape and is characteristic of a wheel which has been taken beyond its normal operational speed limit. Recommendations: The reason for turbocharger overspeeding needs to be investigated on the vehicle. Possible contributing factors: performance tuning, fuelling problems, poor combustion causing high level of deposits in VNT (vanes blocked). Actuator not controlled correctly: ECU problems, command from ECU not reaching actuator, wiring/connection faults, actuator hose leakage, PWM valve faulty, hose blow-off etc may be contributing factors. Blocked/restricted air filter or hoses.

The turbos failed due to overspeed, and were not happy pushing 37 psi of boost for extended durations. Both failures were consistent in nature with respect to how they occurred, as well as with respect to the time period/mileage as the tunes and driving style were more or less identical in nature.

I did not bother sending in the second unit for a claim.

I would recommend either the Garrett GTX Gen 2 line, as those are extremely robust, (I have run a GTX3071r , and GTX3076r in the past) or Precision CEA to avoid going through similar hassles.

I am now swapping in a Precision 6466 CEA Gen 2 (sometime this week).

Hope this helps some of you decide. If you do purchase a G Series Garrett turbo, don't make the mistake i made; do buy a turbo speed sensor, and follow it religiously as part of the tuning process.
beemba is offline   Reply With Quote
Old 10-06-2020, 08:00 AM   #53
Karlot
Scooby Newbie
 
Member#: 339923
Join Date: Dec 2012
Location: Gainesville, VA
Vehicle:
2006 Impreza WRX STi
grey

Default

^^damn dude. i'm sorry to hear that. that actually has pushed me more towards the gtx gen2 setup lol.
Karlot is offline   Reply With Quote
Old 10-06-2020, 08:02 AM   #54
Karlot
Scooby Newbie
 
Member#: 339923
Join Date: Dec 2012
Location: Gainesville, VA
Vehicle:
2006 Impreza WRX STi
grey

Default

Beemba do you think they would be robust at a lower boost level? and if so how much before they are spinning too fast?
Karlot is offline   Reply With Quote
Old 10-06-2020, 10:50 AM   #55
subaru_gc8
Scooby Specialist
 
Member#: 29292
Join Date: Nov 2002
Chapter/Region: SCIC
Location: Orange County CA
Vehicle:
2004 WRX wagon
silver

Default

Quote:
Originally Posted by beemba View Post
Just an update on my ride, reading through the last few pages of posts here, let me chime in with my personal experience on not one, but two Garrett G35-900 turbos i have been through. The first failed at ~1260 mi. the second failed at ~1430 mi.

The nature of failure was very gradual, with a faint, low frequency "Police siren" or "wooooo" noise accompanying spool, that gradually got louder to the point where the compressor inducer was seen to make contact with the compressor housing, and the shaft was seen to have axial runout when rotated.

Oil feed lines on both were brand new. No oiling issues, as all Oil parameters are monitored. No coolant supply problems either.

Tune was carried out by the most respected JDM Builder and tuner here in Dubai, and happens to receive, build and tune vehicles from all over the middle east and north Africa.

The first turbo was sent to Garrett for inspection, and they responded with the following:



880695-5001S

Analysis Findings : Rotor damage - Overspeed -
Technician Conclusion: Turbocharger returned with rubbing wheels vs. contours. Damage of compressor piston rings and overheated of ball bearing as a consequence of Turbo overspeed. During overspeeding cycles, the excessive growth of the compressor wheel may cause a permanent deformation (growth) of the central bore of the wheel, which forms into a barrel shape and is characteristic of a wheel which has been taken beyond its normal operational speed limit. Recommendations: The reason for turbocharger overspeeding needs to be investigated on the vehicle. Possible contributing factors: performance tuning, fuelling problems, poor combustion causing high level of deposits in VNT (vanes blocked). Actuator not controlled correctly: ECU problems, command from ECU not reaching actuator, wiring/connection faults, actuator hose leakage, PWM valve faulty, hose blow-off etc may be contributing factors. Blocked/restricted air filter or hoses.

The turbos failed due to overspeed, and were not happy pushing 37 psi of boost for extended durations. Both failures were consistent in nature with respect to how they occurred, as well as with respect to the time period/mileage as the tunes and driving style were more or less identical in nature.

I did not bother sending in the second unit for a claim.

I would recommend either the Garrett GTX Gen 2 line, as those are extremely robust, (I have run a GTX3071r , and GTX3076r in the past) or Precision CEA to avoid going through similar hassles.

I am now swapping in a Precision 6466 CEA Gen 2 (sometime this week).

Hope this helps some of you decide. If you do purchase a G Series Garrett turbo, don't make the mistake i made; do buy a turbo speed sensor, and follow it religiously as part of the tuning process.
wow thats pretty crappy, can i ask what boost numbers you were pushing on the g35 900?
subaru_gc8 is online now   Reply With Quote
Old 10-11-2020, 02:30 AM   #56
spdracerut
Scooby Newbie
 
Member#: 269226
Join Date: Jan 2011
Default

Quote:
Originally Posted by beemba View Post
The turbos failed due to overspeed, and were not happy pushing 37 psi of boost for extended durations. Both failures were consistent in nature with respect to how they occurred, as well as with respect to the time period/mileage as the tunes and driving style were more or less identical in nature.
[/b].
Assumed 37psi as measured at the intake manifold, so throw in a few psi for pressure drop in the IC piping along with pressure drop at the compressor inlet, so ballparked the pressure ratio in the 3.75-4.0 range.

Yeah, you were off the map/past the speed limit on the G35-900 assuming you were past ~65lbs min. To be fair, you don't take an engine with a redline of 8k rpms, spin it to 9k rpms and expect it to last that long. The G35-1050 would have been a better match for your boost target. At a pressure ratio of 4.0, you could've flowed 80 lbs/min.

As you found out, a speed sensor is critical if you're going to push the limits.
spdracerut is offline   Reply With Quote
Old 10-11-2020, 02:37 AM   #57
spdracerut
Scooby Newbie
 
Member#: 269226
Join Date: Jan 2011
Default

Quote:
Originally Posted by Karlot View Post
Beemba do you think they would be robust at a lower boost level? and if so how much before they are spinning too fast?
Garrett publishes the compressor maps for all their turbos. The top speed line is the safe limit.

Below are the maps for the G35-900 and G35-1050. As you can see, if you want to play in that high pressure ratio area above 3.75, the G35-1050 is the better choice.


spdracerut is offline   Reply With Quote
Old 10-22-2020, 02:37 PM   #58
Karlot
Scooby Newbie
 
Member#: 339923
Join Date: Dec 2012
Location: Gainesville, VA
Vehicle:
2006 Impreza WRX STi
grey

Default

^^^^Unfortunately i have no idea how to read that.
Karlot is offline   Reply With Quote
Old 10-22-2020, 03:37 PM   #59
BlackFighter
Scooby Specialist
 
Member#: 193940
Join Date: Nov 2008
Location: Philly
Vehicle:
2004 WRX STI Black
RalliSpec Shortblock

Default

BlackFighter is offline   Reply With Quote
Old 10-22-2020, 04:05 PM   #60
Scuby04STi
Scooby Specialist
 
Member#: 328635
Join Date: Aug 2012
Chapter/Region: NWIC
Location: Portland*
Vehicle:
2004 STi GTX3076R
Rally Blue

Default

Quote:
Originally Posted by BlackFighter View Post
Thank you, that just saved me a lot of typing. LOL
Scuby04STi is offline   Reply With Quote
Old 10-23-2020, 10:40 AM   #61
Karlot
Scooby Newbie
 
Member#: 339923
Join Date: Dec 2012
Location: Gainesville, VA
Vehicle:
2006 Impreza WRX STi
grey

Default

Quote:
Originally Posted by BlackFighter View Post



Thank you lol. i'm gonna read this now. I appreciate it.
Karlot is offline   Reply With Quote
Old 10-24-2020, 02:12 PM   #62
spdracerut
Scooby Newbie
 
Member#: 269226
Join Date: Jan 2011
Default

Quote:
Originally Posted by Karlot View Post
Thank you lol. i'm gonna read this now. I appreciate it.
With some more math involved.
https://motoiq.com/turbo-tech-calcul...rett-gtx-gen2/
spdracerut is offline   Reply With Quote
Old Yesterday, 09:47 AM   #63
bigAle06
Scooby Newbie
 
Member#: 170306
Join Date: Jan 2008
Location: Florida
Default

Just changed to a new G30-900. It should be done in the next few weeks and should have some results to post. Switched from a gen 1 Garret GTX 3582R, wanted a bit better spool and was only looking for around 600WHP on e85. Old setup made ~550whp for the last 6 years on 93.


-Alex
bigAle06 is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

All times are GMT -4. The time now is 01:04 PM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2020, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2020 Axivo Inc.
Copyright ©1999 - 2019, North American Subaru Impreza Owners Club, Inc.

As an Amazon Associate I earn from qualifying purchases.