Faeflora

iTrader: (2)

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.

18psi

iTrader: (76)

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.

Faeflora

iTrader: (2)

Yeah Fae I agree look at this NASIOC ****

http://forums.nasioc.com/forums/showthread.php?t=602674

Faeflora

iTrader: (2)

It doesn't make sense to me :(

fmowry

iTrader: (8)

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?

Faeflora

iTrader: (2)

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

Braineack

iTrader: (62)

He copy and pasted Joe's post.

shlammed

iTrader: (8)

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.

y8s

iTrader: (8)

thread title rule fail.

Faeflora

iTrader: (2)

I can't get EBC to replicate MBC because tuning EBC has been very frucking frustrating.

Faeflora

iTrader: (2)

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.

Der_Idiot

iTrader: (2)

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..

Faeflora

iTrader: (2)

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:

shlammed

iTrader: (8)

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.