Notices
Forced Induction Turbochargers and Superchargers..Got Boost?

5AT Boost Creeping up from 7psi to 9+psi under 3rd to 4'th shift

Thread Tools
 
Search this Thread
 
Old Jun 14, 2007 | 01:16 PM
  #1  
GBoger's Avatar
GBoger
Thread Starter
Registered User
 
Joined: Jan 2007
Posts: 730
Likes: 1
From: Charlotte
Default 5AT Boost Creeping up from 7psi to 9+psi under 3rd to 4'th shift

I have a 5AT running a ST setup and My boost holds steady for the most part until i do the 3-4 shift at which point it goes up to 9 and sometimes almost 10 psi. I am on a stock block so this is scaring me a little. I'm also using a manual boost controller right now. I've read that you can do somethings to the wastegate to help this but most of that has been from people with 6MT's. Do you guys think an Electronic Boost controller would help this? Is this a common characteristic of AT's? And if so is this something I should worry about?
Reply
Old Jun 14, 2007 | 01:20 PM
  #2  
MIAPLAYA's Avatar
MIAPLAYA
Registered User
iTrader: (3)
 
Joined: Jul 2003
Posts: 11,373
Likes: 0
From: Escondido
Default

Originally Posted by GBoger
I have a 5AT running a ST setup and My boost holds steady for the most part until i do the 3-4 shift at which point it goes up to 9 and sometimes almost 10 psi. I am on a stock block so this is scaring me a little. I'm also using a manual boost controller right now. I've read that you can do somethings to the wastegate to help this but most of that has been from people with 6MT's. Do you guys think an Electronic Boost controller would help this? Is this a common characteristic of AT's? And if so is this something I should worry about?
Which single turbo kit are you running?
Reply
Old Jun 14, 2007 | 01:41 PM
  #3  
minus500's Avatar
minus500
Banned
iTrader: (20)
 
Joined: Nov 2005
Posts: 175
Likes: 0
From: MD
Default

On my 00' S4 with hybrids, I ran a manual boost controller and had the same problem only my boost increased with every gear. I think an EBC would help keep the boost consistent between each gear.
Reply
Old Jun 14, 2007 | 01:42 PM
  #4  
GBoger's Avatar
GBoger
Thread Starter
Registered User
 
Joined: Jan 2007
Posts: 730
Likes: 1
From: Charlotte
Default

sorry for the dumb question but what are hybrids? are you running an AT?
Reply
Old Jun 14, 2007 | 01:51 PM
  #5  
Mike@IOS's Avatar
Mike@IOS
Sponsor
IOS Performance
 
Joined: Jan 2005
Posts: 57
Likes: 0
From: Phoenix, AZ
Default

higher loads will always cause your boost to go up. Unless you have a boost setting much higher than spring pressure and a EBC to smooth it out. A smaill range in boost is normal. if your boost is too high, you will need to go with a lower spring rate.
Reply
Old Jun 14, 2007 | 01:55 PM
  #6  
JoeDirtPharmD's Avatar
JoeDirtPharmD
Registered User
iTrader: (9)
 
Joined: Apr 2005
Posts: 726
Likes: 0
From: Phoenix
Default

nm - post deleted
Reply
Old Jun 14, 2007 | 02:31 PM
  #7  
minus500's Avatar
minus500
Banned
iTrader: (20)
 
Joined: Nov 2005
Posts: 175
Likes: 0
From: MD
Default

Originally Posted by GBoger
sorry for the dumb question but what are hybrids? are you running an AT?
Hybrids are turbos that uses components from two or more turbos. For instance my stock Audi turbos were K03's and my hybrids were K04/K16's inside the stock housing. So basically instead of K03 wheels I had a K16 compressor wheel and a K04 turbine wheel inside ported stock housings. The Audi was manual but my G is a built 5AT.
Reply
Old Jun 14, 2007 | 02:31 PM
  #8  
GBoger's Avatar
GBoger
Thread Starter
Registered User
 
Joined: Jan 2007
Posts: 730
Likes: 1
From: Charlotte
Default

Originally Posted by Mike@IOS
higher loads will always cause your boost to go up. Unless you have a boost setting much higher than spring pressure and a EBC to smooth it out. A smaill range in boost is normal. if your boost is too high, you will need to go with a lower spring rate.
so you do think a ebc would help? I know it should fluctuate a little bit but I'm hoping 3psi fluctuation is not normal.
Reply
Old Jun 14, 2007 | 02:33 PM
  #9  
Mike@IOS's Avatar
Mike@IOS
Sponsor
IOS Performance
 
Joined: Jan 2005
Posts: 57
Likes: 0
From: Phoenix, AZ
Default

Originally Posted by GBoger
so you do think a ebc would help? I know it should fluctuate a little bit but I'm hoping 3psi fluctuation is not normal.
it depends on a few factors such as how well your whole wg system is designed. I would go with a lower psi spring and use a good quality EBC, such as SBC ID to control boost.
Reply
Old Jun 14, 2007 | 05:40 PM
  #10  
DanielW's Avatar
DanielW
Banned
iTrader: (27)
 
Joined: Sep 2006
Posts: 3,485
Likes: 0
From: Concord, North Carolina
Default

good info... I've heard that you can port out the wastegate or something and that will help. Anything to this?

Is this a common characteristic of an automatic transmision? I thought i read that somewhere.

Last edited by DanielW; Jun 15, 2007 at 05:15 AM.
Reply
Old Jun 14, 2007 | 07:52 PM
  #11  
abyss's Avatar
abyss
Registered User
 
Joined: Aug 2005
Posts: 4,318
Likes: 0
From: Missouri
Default

Originally Posted by danielwebb
Thanks for the good info... I've heard that you can port out the wastegate or something and that will help. Anything to this?

Is this a common characteristic of an automatic transmision? I thought i read that somewhere.
Boost spikes are very common on auto's. A proper WG is usually the solution from my readings in the past. Though thats just what I have read an I am no expert.
Reply
Old Jun 14, 2007 | 09:52 PM
  #12  
GTM's Avatar
GTM
Vendor - Former Vendor
iTrader: (12)
 
Joined: Sep 2006
Posts: 2,189
Likes: 1
From: California
Default

You could purchase a HKS EVC 6 with the EasyWriter software and program it to drop boost at a certain speed and throttle position.

Let me know if you need one or help setting it up.

-George
GT Motorsports
Reply
Old Jun 15, 2007 | 06:17 PM
  #13  
DanielW's Avatar
DanielW
Banned
iTrader: (27)
 
Joined: Sep 2006
Posts: 3,485
Likes: 0
From: Concord, North Carolina
Default

how is the apexi unit compared to the hks?
Reply
Old Jun 22, 2007 | 04:35 AM
  #14  
DanielW's Avatar
DanielW
Banned
iTrader: (27)
 
Joined: Sep 2006
Posts: 3,485
Likes: 0
From: Concord, North Carolina
Default

???
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
apex locator
Autocross/Road
10
Jul 23, 2021 02:27 AM
Colombo
Forced Induction
35
Nov 9, 2020 10:27 AM
sherm
Engine & Drivetrain
15
Apr 11, 2020 05:21 PM
ars88
Zs & Gs For Sale
18
Apr 4, 2016 07:52 AM
kyin
New Owners
12
Oct 15, 2015 05:54 AM




All times are GMT -8. The time now is 03:54 AM.