Do I need a MBC?
01-12-2009, 04:35 PM
#1
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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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01-12-2009, 05:29 PM
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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?
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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01-12-2009, 05:38 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.
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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01-12-2009, 05:51 PM
#9
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.
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.
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?
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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01-12-2009, 09:19 PM
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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 :(
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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01-13-2009, 03:05 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.
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01-13-2009, 03:19 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.
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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