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

8.7 spring only hitting 6 psi

Thread Tools
 
Search this Thread
 
Old 05-04-2010 | 08:05 PM
  #1  
Crafty55's Avatar
Thread Starter
Senior Member
10 Year Member
5 Year Member
SL Member
 
Joined: Aug 2007
Posts: 104
From: Arizona
Default 8.7 spring only hitting 6 psi

Well, I got my first tune and dyno on monday.

I have an 8.7 psi spring in, but the most they could squeeze out was 6 psi and 230 hp.

I have 550 cc injectors, TurboToyotas kit.

Any thoughts? I did do a search btw and didn't come across anything.
Old 05-04-2010 | 08:14 PM
  #2  
weezyfbayba's Avatar
Senior Member
10 Year Member
5 Year Member
Team ScionEyed
SL Member
 
Joined: Mar 2009
Posts: 4,354
Default

vac leaks or exhaust leaks at the wg?
Old 05-04-2010 | 08:18 PM
  #3  
Crafty55's Avatar
Thread Starter
Senior Member
10 Year Member
5 Year Member
SL Member
 
Joined: Aug 2007
Posts: 104
From: Arizona
Default

They dyno shop tested for vac/exhaust leaks and said I didn't have any.
Old 05-04-2010 | 08:48 PM
  #4  
FromTheOld's Avatar
Senior Member
10 Year Member
5 Year Member
SL Member
 
Joined: Jul 2008
Posts: 707
Default

Well in that case, make sure you have the right wastegate spring
Old 05-04-2010 | 08:51 PM
  #5  
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 FromTheOld
Well in that case, make sure you have the right wastegate spring
Haha I did, but thanks for the the "do'h" check. Gotta always check those first haha.
Old 05-04-2010 | 10:33 PM
  #6  
Crafty55's Avatar
Thread Starter
Senior Member
10 Year Member
5 Year Member
SL Member
 
Joined: Aug 2007
Posts: 104
From: Arizona
Default

Well, when I get home, I think im just gonna triple check all my couplers and do the soapy water test to see if there are any larger leaks that maybe they missed at the dyno shop.
Old 05-04-2010 | 10:53 PM
  #7  
johnnyb305mia's Avatar
Senior Member
10 Year Member
5 Year Member
SL Member
 
Joined: Jan 2010
Posts: 1,122
From: Pembroke Pines, FL
Default

what wastegate r u using? tial???
Old 05-04-2010 | 11:31 PM
  #8  
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 johnnyb305mia
what wastegate r u using? tial???

Yea, it's a tial.
Old 05-05-2010 | 12:15 AM
  #9  
cburglb34's Avatar
Banned
10 Year Member
5 Year Member
SL Member
 
Joined: Nov 2007
Posts: 2,893
From: Germantown, MD
Default

ive had this issue before... seeing as 35mm and 38mm wastgates use same size springs...i figure ill order a 8.7 35mm spring for my 38 and well it ended being good for like 6 psi if that...i just ended using a boost controller
Old 05-05-2010 | 02:17 AM
  #10  
johnnyb305mia's Avatar
Senior Member
10 Year Member
5 Year Member
SL Member
 
Joined: Jan 2010
Posts: 1,122
From: Pembroke Pines, FL
Default

i would make sure ur spring is an 8psi spring first and if anything get a boost controller and call it a day but also i would double check for any vac/boost leaks what color is ur spring do u know?
Old 05-05-2010 | 02:28 AM
  #11  
crush02342002's Avatar
Senior Member
10 Year Member

5 Year Member
SL Member
iTrader: (2)
 
Joined: Feb 2008
Posts: 11,271
From: Houston, TX
Default

It happens to me cause of the stock axle back im running, but with my qtp open I get all of that 8psi and sometimes touches into 9psi.
Old 05-05-2010 | 02:47 AM
  #12  
Crafty55's Avatar
Thread Starter
Senior Member
10 Year Member
5 Year Member
SL Member
 
Joined: Aug 2007
Posts: 104
From: Arizona
Default

Ok, thanks all. I'll check into all these suggestions and get back to you. First I'll check for exhaust/vac leaks one more time.

After that, I think it may be the restrictive exhaust. The kit came with an s-pipe, but I am running the stock midpipe with the cat and resonator and a tanabe axel back.
Old 05-05-2010 | 07:16 PM
  #13  
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 Crafty55
Well, I got my first tune and dyno on monday.

I have an 8.7 psi spring in, but the most they could squeeze out was 6 psi and 230 hp.

I have 550 cc injectors, TurboToyotas kit.

Any thoughts? I did do a search btw and didn't come across anything.
Are you sure it's an 8 PSI spring?

Boost leak?

Altitude? Couple this with a core that steals .5-1 PSI of pressure drop and you have a winner.
Old 05-05-2010 | 07:53 PM
  #14  
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

also what wastegate size? tial 38mm and 44mm have different color codes on their springs
Old 05-19-2010 | 06:31 PM
  #15  
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
Are you sure it's an 8 PSI spring?

Boost leak?

Altitude? Couple this with a core that steals .5-1 PSI of pressure drop and you have a winner.

Yea, it's an 8.7 spring, had the tuners dbl check and try one of their 8.7 springs to make sure.

Boost stays steady, doesn't creep or leak.

I'm in arizona, so no crazy altitudes.


I do have a small exhaust leak at the head that I need to fix. Passenger side lower corner isn't seated correctly and I have the stock mid-pipe with the restrictive cat.

I'm guessing it's the combo of the exhaust leak and midpipe.
Old 05-19-2010 | 06:31 PM
  #16  
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
also what wastegate size? tial 38mm and 44mm have different color codes on their springs

It's the tial 38mm wastegate.
Old 05-19-2010 | 06:40 PM
  #17  
polskifacet's Avatar
Junior Member
 
Joined: Oct 2008
Posts: 28
Default

is it new? I had to take mine apart and clean it ... had a similar issue before.
Old 05-19-2010 | 07:04 PM
  #18  
Crafty55's Avatar
Thread Starter
Senior Member
10 Year Member
5 Year Member
SL Member
 
Joined: Aug 2007
Posts: 104
From: Arizona
Default

Tried that as well, but didn't help.
Old 05-19-2010 | 11:47 PM
  #19  
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

are you sure they did boost leak test? or maybe they just checked your clamps if theyre tight or checked it visually? i had a huge boost leak and i still creep boost, 7 psi one 6psi spring
Old 05-20-2010 | 05:32 AM
  #20  
Crafty55's Avatar
Thread Starter
Senior Member
10 Year Member
5 Year Member
SL Member
 
Joined: Aug 2007
Posts: 104
From: Arizona
Default

Yea, I had another shop check as well. They told me the midpipe as well. Sounds like that's the issue.


Quick Reply: 8.7 spring only hitting 6 psi



All times are GMT. The time now is 12:11 AM.