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Old 01-12-2009, 05:35 PM   #1
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Default Do I need a MBC?

I got the new turbo in and it included a WG actuator that can hold 14PSI. I know the EBC would have benifits but I'm was using a MBC. Is there a point to put on the MBC on the car when the WG actuator itself can hold the 14 PSI I want?
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Old 01-12-2009, 05:37 PM   #2
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even set to 14psi, you'll see better spool with a MBC inline.
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Old 01-12-2009, 06:06 PM   #3
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WAY better spool lol....
on wga you will see the 14psi whenever the turbo feels like it, with an mbc set to 14psi you will see 14psi AS SOON as the turbo can possibly make that.
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Old 01-12-2009, 06:14 PM   #4
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Quote:
Originally Posted by 18psi View Post
WAY better spool lol....
on wga you will see the 14psi whenever the turbo feels like it, with an mbc set to 14psi you will see 14psi AS SOON as the turbo can possibly make that.
Same hold true for my (planned) 8PSI or is it less critical? I was thinking still critical. Even if the WG starts creeping open even 2-3 psi early, that is 25-40% of my total pressure.
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Old 01-12-2009, 06:21 PM   #5
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Same hold true for my (planned) 8PSI or is it less critical? I was thinking still critical. Even if the WG starts creeping open even 2-3 psi early, that is 25-40% of my total pressure.
you are absolutely right....that is why I will be running my hallman es mbc even on the measly 8psi that I am planning to run as well
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Old 01-12-2009, 06:29 PM   #6
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Ok answer accepted. Thanks!

Now why? If the MBC only restricts the flow to the actuator what would be the difference? I understand the EBC can hold flow until desired boost is reached and then let go but the MBC is just a spring, won't that just bleed a little more and more like like the actuator?

Another Q, when I use the MBC what do I adjust the actuator rod to? Leave it where it was from the factory or make it tighter or looser?
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Old 01-12-2009, 06:38 PM   #7
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the MBC limits any boost from entering the wastegate actuator. Any boost, be it say 5psi as the turbo builds, will slowly cause the actuator to push the rod out and open the wastegate. A 14psi wastegate actuator means 14psi peak boost. Since the MBC uses a ball and spring, you can severely limit the flow of boost entering the actuator can. Then it's like the turbo doesn't "think" it's making any boost and the wastegate stays shut during spool. Once the preload of the MBC spring is achieved, then and only then will boost enter the can at a full set amount...14psi in your case.

Since you're holding the wastegate closed longer, it will spool faster; no exhaust is being diverted around the turbine and directly into the exhaust.

The tighter the rod the faster the spool, it may increase the lowest boost possible if it prevent the wastegate from opening enough to bleed enough exhaust around the turbine to maintain a specific boost level.
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Old 01-12-2009, 06:45 PM   #8
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MBC helped my spool. MBC FTW.
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Old 01-12-2009, 06:51 PM   #9
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Quote:
Originally Posted by Braineack View Post
the MBC limits any boost from entering the wastegate actuator. Any boost be it say 5psi as the turbo build will slowl cause the actuator to push the rod out and open the wastegate. a 14psi wastegate actuator means 14psi peak boost. Since the MBC uses a ball and spring, you can severely limit the flow of boost entering the actuator can. There it's like the turbo doesn't "think" it's making any boost and the wastegate stays shut during spool. Once the preload of the MBC spring is achieved, then and only then will boost enter the can at a full set amount...14psi in your case.

Since you're holding the wastegate closed longer, it will spool faster; no exhaust is being diverted around the turbine and directly into the exhaust.

The tighter the rod the faster the spool, it may increase the lowest boost possible if it prevent the wastegate from opening enough to bleed enough exhaust around the turbine to maintain a specific boost level.
couldnt have worded it better if I tried
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Ok answer accepted. Thanks!

Now why? If the MBC only restricts the flow to the actuator what would be the difference? I understand the EBC can hold flow until desired boost is reached and then let go but the MBC is just a spring, won't that just bleed a little more and more like like the actuator?

Another Q, when I use the MBC what do I adjust the actuator rod to? Leave it where it was from the factory or make it tighter or looser?
Be very careful when adjusting the mbc. they are touchy little *******. you want to have it loose, or set as low as possible, and start from there. after a while you get the hang of it and can guestimate how many turns = how many psi increase.
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Old 01-12-2009, 07:04 PM   #10
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couldnt have worded it better if I tried

yes, it could of had better grammar.
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Old 01-12-2009, 10:10 PM   #11
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Quote:
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yes, it could of had better grammar.
could have had
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Old 01-12-2009, 10:19 PM   #12
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This is good to know.

Mike, how does yours feel? I haven't posted videos/response because I've been fighting with MS/Injectors for the past few days. 10:1 + Boost = bog and spitting :(
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Old 01-12-2009, 10:54 PM   #13
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Quote:
Originally Posted by SloS13 View Post
could have had
passive voice ftl.
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Old 01-13-2009, 04:05 AM   #14
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Tough to say so far. With out MBC the WG gives me a SOLID 10 PSI but I was running 14 on the old setup. I have not got a change to tune it yet but I have been watching the WB closely and it seems to only be a point higher. Leanest I have seen it so far is 10.9 After some data loging and makeing sure I don't kill it I will up the boost, maybe tomorrow.

Quote:
Originally Posted by miatamania View Post
This is good to know.

Mike, how does yours feel? I haven't posted videos/response because I've been fighting with MS/Injectors for the past few days. 10:1 + Boost = bog and spitting :(
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Old 01-13-2009, 04:19 AM   #15
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FAR better spool. After I pulled my clogged cat and ported the WG I had to retune my EBC map and I messed up the scales at first, and the car felt AWFUL. I seriously thought it was broken. Adjusted the scale so the EBC was actually on at 20% throttle at 3000rpm, and it was back to normal.

Hell, I would run the MS EBC. Run it at the max DC you can before it starts to affect the boost. It will make a big difference in response.
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Old 01-13-2009, 10:03 AM   #16
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Quote:
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could have had
see. i fail. I have yet to learn the correct usage of have vs of. I blame my ADHD.
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Old 04-20-2010, 04:39 PM   #17
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If I add the Hallman Mbc to my car and leave it at the same 8lbs I'm running now without it, will I still need to retune the Link ecu since it will spool faster?
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Old 04-20-2010, 05:16 PM   #18
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possibly/probably
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Old 04-20-2010, 05:18 PM   #19
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I wonder if an MBC would make my TiAL MV-S function better?
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