Notices
DIY Turbo Discussion greddy on a 1.8? homebrew kit?

Boost problems

Thread Tools
 
Search this Thread
 
Old May 29, 2018 | 02:31 PM
  #1  
RyanRaduechel's Avatar
Thread Starter
Senior Member
iTrader: (10)
 
Joined: Jul 2009
Posts: 1,405
Total Cats: 149
From: Oakdale, CA
Default Boost problems

Hey all,
So I would like to start out by saying I am stumped, and I hope it is something really simple that I am over looking. I am having issues of not being able to maintain boost pressure. It's a tial v60 gate, Hallman MBC. I thought the spring pack that came with it was 12 psi, but it turned out to be 6 psi. So we changed the spring to a 15 psi spring. My problem and my confusion is this, even with a 6 psi spring, the boost controller should be able to hold more than the spring pressure, I read somewhere it should be able to hold 150 % of the spring pressure, which would've been around 9 psi. But that wasn't the case, it was only making 5-6 psi, we changed the spring to a 15 psi spring, and it made 15 psi even with the boost controller maxed out.

So what am I doing wrong, do I not have enough manifold/line pressure on the wastegate diaphragm to keep the wastegate closed? The wastegate is setup with the source coming from post throttle body, to the MBC, to the side port of the wastegate, top of the wastegate is VTA. Do I need to go with an electric 3 port boost controller which would utilize both ports on the gate?

Because shoving a socket in the wastegate to get some more psi out of it probably wasn't the best idea, she shot up to 27-28 psi real quick before blowing my coupler
Old May 29, 2018 | 02:34 PM
  #2  
18psi's Avatar
VladiTuned
iTrader: (76)
 
Joined: Apr 2008
Posts: 35,821
Total Cats: 3,482
Default

my .02: hallman comes with 2 springs. from my exp anything over 14-15psi and you need the heavier one. (the Subaru turbo's I usually tune have a 10psi wga).
Also a monster gate like that you probably want a larger than the standard 5/16 vac line.

If you want it rock solid no matter what, time for a 4port mac valve and set up both ports
Old May 29, 2018 | 03:29 PM
  #3  
RyanRaduechel's Avatar
Thread Starter
Senior Member
iTrader: (10)
 
Joined: Jul 2009
Posts: 1,405
Total Cats: 149
From: Oakdale, CA
Default

Originally Posted by 18psi
my .02: hallman comes with 2 springs. from my exp anything over 14-15psi and you need the heavier one. (the Subaru turbo's I usually tune have a 10psi wga).
Also a monster gate like that you probably want a larger than the standard 5/16 vac line.

If you want it rock solid no matter what, time for a 4port mac valve and set up both ports
I'm running 1/4" push lock fittings on everything. I have no issue going away from the manual boost controller. Obviously going EBC would provide more control and adjustability, just need to get it set up in the ecu. That's interesting though, I didn't know that boost controller itself had different sized springs. You gonna tune this thing for me?
Old May 29, 2018 | 03:43 PM
  #4  
18psi's Avatar
VladiTuned
iTrader: (76)
 
Joined: Apr 2008
Posts: 35,821
Total Cats: 3,482
Default

haha, I'm genuinely scared just looking at your car. I thought its already tuned? I see it rippin around going 1000mph

Most/All modern standalones can control a 4port mac valve without any issue. But I'd try the spring first because its like 30 sec to swap. I have one too if you wanna borrow
Old May 29, 2018 | 03:56 PM
  #5  
RyanRaduechel's Avatar
Thread Starter
Senior Member
iTrader: (10)
 
Joined: Jul 2009
Posts: 1,405
Total Cats: 149
From: Oakdale, CA
Default

Originally Posted by 18psi
haha, I'm genuinely scared just looking at your car. I thought its already tuned? I see it rippin around going 1000mph

Most/All modern standalones can control a 4port mac valve without any issue. But I'd try the spring first because its like 30 sec to swap. I have one too if you wanna borrow
lol no, it hasn't been tuned yet. I am using a basemap from Holley that I adjusted the injector size and have been running it. I don't really plan on running this car until late September/October, so if going with the Mac valve is the right way to go, might as well do it now
Old May 29, 2018 | 03:58 PM
  #6  
18psi's Avatar
VladiTuned
iTrader: (76)
 
Joined: Apr 2008
Posts: 35,821
Total Cats: 3,482
Default

If holley has boost by gear or boost by speed, or any modern boost control, I'd say yes definitely. Even on my weaksauce 400hp Subaru I utilize this, I can only imagine how much helpful it would be on your nasty beast.
Old May 29, 2018 | 04:49 PM
  #7  
RyanRaduechel's Avatar
Thread Starter
Senior Member
iTrader: (10)
 
Joined: Jul 2009
Posts: 1,405
Total Cats: 149
From: Oakdale, CA
Default

Originally Posted by 18psi
If holley has boost by gear or boost by speed, or any modern boost control, I'd say yes definitely. Even on my weaksauce 400hp Subaru I utilize this, I can only imagine how much helpful it would be on your nasty beast.
It does have all that fancy stuff; boost per gear, mph, RPM, and TPS. I think it would be fun to hook up a scramble button for an extra 5 psi on demand
Old May 31, 2018 | 12:50 PM
  #8  
sixshooter's Avatar
Moderator
iTrader: (12)
 
Joined: Nov 2008
Posts: 22,157
Total Cats: 3,537
From: Tampa, Florida
Default

So you are saying your wastegate signal is coming from the intake manifold which is post throttle body, correct?
Old Jun 1, 2018 | 03:04 PM
  #9  
RyanRaduechel's Avatar
Thread Starter
Senior Member
iTrader: (10)
 
Joined: Jul 2009
Posts: 1,405
Total Cats: 149
From: Oakdale, CA
Default

Originally Posted by sixshooter
So you are saying your wastegate signal is coming from the intake manifold which is post throttle body, correct?
That is correct, I made a distribution block which is fed by a 3/8 nylon line post throttle body. Then the BOV, wastegate, FPR, and boost gauge are all feeding off that distribution block. The MAP sensor has it's own dedicated signal line
Old Jun 1, 2018 | 03:12 PM
  #10  
18psi's Avatar
VladiTuned
iTrader: (76)
 
Joined: Apr 2008
Posts: 35,821
Total Cats: 3,482
Default

Might wanna source pre-tb so you don't overspin the turbo at part throttle, though it's not a huge deal in your case either way.
(is your LS drive by wire?)
Old Jun 1, 2018 | 03:13 PM
  #11  
borka's Avatar
Elite Member
iTrader: (1)
 
Joined: Mar 2014
Posts: 1,557
Total Cats: 197
From: Jacksonville, FL
Default

I had the the biggest trouble with my ebc solenoid, and could not reliably calibrate it to hold boost correctly.
It shared the same vacuum line with my BOV using a Tee.
I gave my BOV and EBC solenoid their own vacuum lines and problem solved.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
JasonC SBB
ECUs and Tuning
15
Sep 19, 2011 03:53 PM
delcbr
DIY Turbo Discussion
21
Oct 4, 2010 05:29 AM
AbeFM
Prefabbed Turbo Kits
15
Jul 22, 2009 03:08 PM
cardriverx
DIY Turbo Discussion
4
Jun 17, 2008 11:39 PM
fluke
DIY Turbo Discussion
12
Jan 30, 2007 03:52 PM




All times are GMT -4. The time now is 08:39 AM.