Notices
General Miata Chat A place to talk about anything Miata

Stiff Schnitzel Boost Control Silk Igloo Snugglespace

Thread Tools
 
Search this Thread
 
Old Jul 14, 2011 | 01:06 AM
  #1  
Faeflora's Avatar
Thread Starter
Elite Member
iTrader: (2)
 
Joined: Jan 2007
Posts: 8,682
Total Cats: 130
From: Los Angeles, CA
Default Stiff Schnitzel Boost Control Silk Igloo Snugglespace

Despite referencing my MBC signal from after the throttle body, I get about 5psi of dick I mean boost sag from 25psi down to 20ishpsi at redline. Fail.

I have a functional EBC but it spools 500RPM later than my MBC and with my GT3071, the difference is noticeable.

I'm thinking that by combining the MBC and EBC I should be able to get a nice and stable 25psi.

Ideas on how to set this up? I am a little boggled on the logic of it.
Old Jul 14, 2011 | 01:40 AM
  #2  
18psi's Avatar
VladiTuned
iTrader: (76)
 
Joined: Apr 2008
Posts: 35,821
Total Cats: 3,482
Default

SEARCH NOOB

Hybrid boost control has been done by a few on here and also very common in the subaru community. works well if set up correctly. IIRC there are even diagrams posted about it here. ill try to find em tomorrow if I'm bored and you still haven't figured this **** out.
Old Jul 14, 2011 | 01:45 AM
  #3  
Faeflora's Avatar
Thread Starter
Elite Member
iTrader: (2)
 
Joined: Jan 2007
Posts: 8,682
Total Cats: 130
From: Los Angeles, CA
Default

Originally Posted by 18psi
SEARCH NOOB

Hybrid boost control has been done by a few on here and also very common in the subaru community. works well if set up correctly. IIRC there are even diagrams posted about it here. ill try to find em tomorrow if I'm bored and you still haven't figured this **** out.
Yeah Fae I agree look at this NASIOC ****

http://forums.nasioc.com/forums/showthread.php?t=602674
Old Jul 14, 2011 | 02:07 AM
  #4  
Faeflora's Avatar
Thread Starter
Elite Member
iTrader: (2)
 
Joined: Jan 2007
Posts: 8,682
Total Cats: 130
From: Los Angeles, CA
Default

Originally Posted by Faeflora
Yeah Fae I agree look at this NASIOC ****

http://forums.nasioc.com/forums/showthread.php?t=602674
It doesn't make sense to me :(
Old Jul 14, 2011 | 08:28 AM
  #5  
fmowry's Avatar
Elite Member
iTrader: (8)
 
Joined: Sep 2006
Posts: 1,907
Total Cats: 6
From: Severn, MD
Default

If you can't get your EBC spooling like your MBC, there is something wrong with your EBC. Fix that and go from there. Adding a larger fucked up, complex mess to your currently smaller fucked, up complex mess will leave you with a fucked up, complex mess in the end.

I'm not being a smart ***, you just need to start simplifying stuff to fix it. The hybrid setup won't fix your problem. Look at the first page in the thread you linked. Then read all 20 pages. You want to fix a problem, not introduce more like a lot of the people in that thread.

As for your sag, maybe you have a mechanical (flow) issue that is not allowing you to hold boost with your big turbo? Head, cams, etc. Or a boost leak that occurs at high pressure?
Old Jul 14, 2011 | 09:29 AM
  #6  
Faeflora's Avatar
Thread Starter
Elite Member
iTrader: (2)
 
Joined: Jan 2007
Posts: 8,682
Total Cats: 130
From: Los Angeles, CA
Default

Hmm ok let me take a look at the mechanical issues- I don't really understand why I wouldn't be able to hold pressure though even with a boost leak since boost control is a closed loop system. The head should be good to go, I have no idea about cams. I should order a boost leak tester though.

I'll mess with my EBC some more too.

Oh BTW while googling I found this on a D series forum. Is this Joe Perez? Or a Joe Perez content thief?

http://www.d-series.org/forums/force...fancy-ebc.html
Old Jul 14, 2011 | 09:36 AM
  #7  
Braineack's Avatar
Boost Czar
iTrader: (62)
 
Joined: May 2005
Posts: 80,552
Total Cats: 4,368
From: Chantilly, VA
Default

He copy and pasted Joe's post.
Old Jul 14, 2011 | 09:41 AM
  #8  
shlammed's Avatar
Elite Member
iTrader: (8)
 
Joined: Dec 2008
Posts: 2,910
Total Cats: 51
From: Kingston, Ontario
Default

why cant you get your ebc to replicate MBC?

0 % duty until it hits 15psi-20% until 25psi and then 80-90% from then on out or wtv holds your boost. unless you have some funked up ebc routing.

EBC based on engine rpm with barometric pressure compensation is best.
Old Jul 14, 2011 | 11:58 AM
  #9  
y8s's Avatar
y8s
DEI liberal femininity
iTrader: (8)
 
Joined: Jun 2005
Posts: 19,338
Total Cats: 574
From: Fake Virginia
Default

thread title rule fail.
Old Jul 14, 2011 | 03:50 PM
  #10  
Faeflora's Avatar
Thread Starter
Elite Member
iTrader: (2)
 
Joined: Jan 2007
Posts: 8,682
Total Cats: 130
From: Los Angeles, CA
Default

Originally Posted by shlammed
why cant you get your ebc to replicate MBC?

0 % duty until it hits 15psi-20% until 25psi and then 80-90% from then on out or wtv holds your boost. unless you have some funked up ebc routing.

EBC based on engine rpm with barometric pressure compensation is best.
I can't get EBC to replicate MBC because tuning EBC has been very frucking frustrating.
Old Jul 14, 2011 | 10:31 PM
  #11  
Faeflora's Avatar
Thread Starter
Elite Member
iTrader: (2)
 
Joined: Jan 2007
Posts: 8,682
Total Cats: 130
From: Los Angeles, CA
Default

Tonight I tried using the venerable ye olde balle aynd springe $20 MBC.



It didn't work. Boost still sagged :( :( :(

Oh, interestingly, I was able to achieve stable boost at 14psi which is BELOW my wastegate spring jpressure of 17psi. :| Please explain how that works.
Attached Thumbnails Stiff Schnitzel Boost Control Silk Igloo Snugglespace-2sfyq.png  
Old Jul 18, 2011 | 02:28 PM
  #12  
Der_Idiot's Avatar
Senior Member
iTrader: (2)
 
Joined: Nov 2007
Posts: 1,489
Total Cats: 29
From: Saint Paul, MN
Default

I have the same issue going on here, sags from 17psi at 4-5.5k down to 16psi at 5.5-7k. I want my torques..
Old Jul 18, 2011 | 08:14 PM
  #13  
Faeflora's Avatar
Thread Starter
Elite Member
iTrader: (2)
 
Joined: Jan 2007
Posts: 8,682
Total Cats: 130
From: Los Angeles, CA
Default

How do you have yours hooked up der?

I have mine hooked up like this:

brake booster line
in port
out port goes to side wastegate port.

I'm wondering if I should hook it up like this:

Old Jul 19, 2011 | 02:20 PM
  #14  
shlammed's Avatar
Elite Member
iTrader: (8)
 
Joined: Dec 2008
Posts: 2,910
Total Cats: 51
From: Kingston, Ontario
Default

set boost cut, just hook the vac line up to the top port of the WG...none on bottom, drive to an rpm where you cant make the boost you want and slowly brakeboost to see if you can make the boost you want.

in my thinking:
a) your WG spring is too weak and will sag
b) your turbo is old and wont spin enough to make full boost at higher rpms.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Full_Tilt_Boogie
Build Threads
84
Apr 12, 2021 04:21 PM
Zaphod
MEGAsquirt
47
Oct 26, 2018 11:00 PM
LucaCarMods
Build Threads
11
Feb 14, 2016 06:13 AM
Trent
WTB
2
Oct 1, 2015 12:15 PM
shooterschmidty
Engine Performance
8
Sep 30, 2015 10:28 PM




All times are GMT -4. The time now is 01:21 PM.