Notices
Scion tC 1G Forced Induction Turbo and supercharger applications...

8.7 spring only hitting 6 psi

Thread Tools
 
Search this Thread
 
Old May 20, 2010 | 02:51 PM
  #21  
Hix's Avatar
Hix
Senior Member
10 Year Member
5 Year Member
SL Member
 
Joined: Dec 2008
Posts: 1,788
From: Houston, TX
Default

Yea same with mine. But I have an 11psi spring and I hit all of 6 psi. I just got a boost controller and cranked it up. No vacuum leaks, small exhaust leak, tial WG, no altitude problems. Figure I'll just get a 30psi spring and hopefully hit 20.
Old May 20, 2010 | 03:15 PM
  #22  
paul_dezod's Avatar
Banned
10 Year Member
5 Year Member
Scionetics
KAD
SL Member
 
Joined: Oct 2005
Posts: 11,936
From: Western NY
Default

Originally Posted by Hix
Yea same with mine. But I have an 11psi spring and I hit all of 6 psi. I just got a boost controller and cranked it up. No vacuum leaks, small exhaust leak, tial WG, no altitude problems. Figure I'll just get a 30psi spring and hopefully hit 20.
What size exhaust?
Old May 20, 2010 | 03:27 PM
  #23  
Crafty55's Avatar
Thread Starter
Senior Member
10 Year Member
5 Year Member
SL Member
 
Joined: Aug 2007
Posts: 104
From: Arizona
Default

Originally Posted by paul_dezod
What size exhaust?
I have 2.5" s-pipe and the Tanabe concept G axel back, which I believe is close to 2.5" as well.

I still have the oem mid-pipe with the stock cat and I think it's a resonator on there.
Old May 20, 2010 | 03:31 PM
  #24  
Ace83's Avatar
Senior Member
10 Year Member
5 Year Member
Ronin Scion
SL Member
Premium Member
iTrader: (6)
 
Joined: Aug 2006
Posts: 11,117
From: TX
Default

i would think there is something else other than the restrictive exhaust... some guys on stock exhaust boost on 8-9 psi fine.. though freeing your back pressure might help
Old May 20, 2010 | 04:23 PM
  #25  
Crafty55's Avatar
Thread Starter
Senior Member
10 Year Member
5 Year Member
SL Member
 
Joined: Aug 2007
Posts: 104
From: Arizona
Default

Originally Posted by Ace83
i would think there is something else other than the restrictive exhaust... some guys on stock exhaust boost on 8-9 psi fine.. though freeing your back pressure might help

Weird. Well, once I get the mid-pipe taken care of, it'll narrow it down for us. I'll let you guys know when I do that and what the results are.
Old May 20, 2010 | 10:37 PM
  #26  
Crafty55's Avatar
Thread Starter
Senior Member
10 Year Member
5 Year Member
SL Member
 
Joined: Aug 2007
Posts: 104
From: Arizona
Default

Any suggestions on good midpipes?
Old May 21, 2010 | 12:00 AM
  #27  
Hix's Avatar
Hix
Senior Member
10 Year Member
5 Year Member
SL Member
 
Joined: Dec 2008
Posts: 1,788
From: Houston, TX
Default

Originally Posted by paul_dezod
What size exhaust?
It was the same with or without exhaust, but right now I have 2.5 exhaust with a stock S-Pipe (I know I know... I got a new s-pipe but it didn't fit the car)
Old May 21, 2010 | 02:56 AM
  #28  
olaHalo's Avatar
Senior Member
10 Year Member
5 Year Member
SL Member
 
Joined: Dec 2006
Posts: 2,191
From: @ home
Default

i had the same problem with literally the same setup
my issue was the wastegate was getting stuck somehow on itself (not opening all the way)
took it apart and cleaned it and it worked from then on it
Old May 21, 2010 | 03:31 AM
  #29  
Ace83's Avatar
Senior Member
10 Year Member
5 Year Member
Ronin Scion
SL Member
Premium Member
iTrader: (6)
 
Joined: Aug 2006
Posts: 11,117
From: TX
Default

^^ yeah that could happen too if wg is stuck open.. ola didnt you ran stock exhaust before on turbo and beat that sti at 9 psi?
Old May 21, 2010 | 03:58 AM
  #30  
olaHalo's Avatar
Senior Member
10 Year Member
5 Year Member
SL Member
 
Joined: Dec 2006
Posts: 2,191
From: @ home
Default

Originally Posted by Ace83
^^ yeah that could happen too if wg is stuck open.. ola didnt you ran stock exhaust before on turbo and beat that sti at 9 psi?
got it on video lmao

yeah im still on stock exhaust
but ill get a cutout sooner or later

which is also why i dont think the OPs problem is exhaust related
Old May 21, 2010 | 02:53 PM
  #31  
Crafty55's Avatar
Thread Starter
Senior Member
10 Year Member
5 Year Member
SL Member
 
Joined: Aug 2007
Posts: 104
From: Arizona
Default

Hmm, the tuner said he cleaned my WG, but everything you guys are stating is making it sound like the wg is getting stuck.

Never taken one apart before. How do I go about cleaning the WG?
Old May 22, 2010 | 02:58 AM
  #32  
emrules2001's Avatar
Senior Member
10 Year Member
5 Year Member
SL Member
 
Joined: Jun 2009
Posts: 603
From: Phoenix, Arizona
Default

Did you get it tuned at UMS? They topped mine out at 6.5psi, and said they could go higher if I had a boost controller.
Old May 22, 2010 | 03:35 AM
  #33  
Crafty55's Avatar
Thread Starter
Senior Member
10 Year Member
5 Year Member
SL Member
 
Joined: Aug 2007
Posts: 104
From: Arizona
Default

They told me the same thing but said my exhaust is the reason it won't go higher than 6.5.
Old Jun 28, 2010 | 08:20 AM
  #34  
vk5112's Avatar
Member
SL Member
 
Joined: May 2009
Posts: 75
From: bako,cali
Default

did u ever get this fixed.

im having the same problem right now
Old Jun 28, 2010 | 06:10 PM
  #35  
DezodDon's Avatar
Senior Member
10 Year Member
5 Year Member
SL Member
 
Joined: Apr 2009
Posts: 782
From: Buffalo, NY
Default

Here are the possible problems.

1. Massive exhaust leak pre turbo.

2. Very restrictive exhaust

3. Incorrect WG spring

4. Massive Boost leak

If they are taking the boost source from the turbo compressor housing and at WOT your boost gauge reads 6 then you have a boost leak somewhere past the outlet of the turbo
Old Jun 29, 2010 | 03:40 PM
  #36  
BlackKnight's Avatar
Senior Member
10 Year Member
5 Year Member
Music City Scions
SL Member
 
Joined: Mar 2009
Posts: 1,372
From: Nashville, TN
Default

Originally Posted by paul_dezod
core that steals .5-1 PSI of pressure.
This.
Old Jul 3, 2010 | 05:28 PM
  #37  
Crafty55's Avatar
Thread Starter
Senior Member
10 Year Member
5 Year Member
SL Member
 
Joined: Aug 2007
Posts: 104
From: Arizona
Default

Originally Posted by DezodDon
Here are the possible problems.

1. Massive exhaust leak pre turbo.

2. Very restrictive exhaust

3. Incorrect WG spring

4. Massive Boost leak

If they are taking the boost source from the turbo compressor housing and at WOT your boost gauge reads 6 then you have a boost leak somewhere past the outlet of the turbo
1. no exhaust leaks

2. only restrictive part of the exhaust I have is the stock midpip, is that considered "very restrictive"?

3. WG spring is correct, i double checked and had the shope check as well

4. No boost leaks.
Old Jul 3, 2010 | 05:30 PM
  #38  
Crafty55's Avatar
Thread Starter
Senior Member
10 Year Member
5 Year Member
SL Member
 
Joined: Aug 2007
Posts: 104
From: Arizona
Default

Originally Posted by BlackKnight
Quote:
Originally Posted by paul_dezod
core that steals .5-1 PSI of pressure.



This.
That would still only bring me to 7 or 7.5...
Old Jul 19, 2010 | 08:38 PM
  #39  
gwopsta's Avatar
Banned
SL Member
 
Joined: Jan 2010
Posts: 270
Default

im going thru the same thing as we speak, no exhaust leaks

went from a tial 8.7 lil blue spring to the big green 13.05

and i was only able to boost up to 10psi, i just knew dezod sent me the wrong spring but i checked and its the right color

i dont think its my wg or my gauge being that it worked perfectly till i replaced the spring. i may have to try cleaning the wg and checking for leaks once again....this sucks

what boost controller does any1 recommend, im hesitant on using these, being that if it fails and has a massive spike im F___ed
Old Jul 19, 2010 | 08:44 PM
  #40  
SoFloTC's Avatar
Senior Member
10 Year Member
5 Year Member
SL Member
iTrader: (3)
 
Joined: Jul 2007
Posts: 5,104
Default

aem truboosttttt



All times are GMT. The time now is 02:35 PM.