boost not changing please help
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From: taos county
boost not changing please help
i got stock evo 8 with manuel boost controller a daily driven car usually set to stock boost went to raise boost for a race the other day and no increace in boost
goes up like 2-3 psi and ive been able to run at almost 25 psi and when i change to boost controller no changes and suggestions please help
goes up like 2-3 psi and ive been able to run at almost 25 psi and when i change to boost controller no changes and suggestions please help
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From: taos county
no... i can turn the boost controller up to where it would be at 25 psi and it dont change my boost... ill turn it up all the way and still no diffrence.... does it sound like a actuator problem???i dont know what the hell is going on...
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From: taos county
im not shure it doesnt really show its just a cheap manul boost controller with an adjuster screw and check ball.....my gauge reads at 17 psi in first and second gear and 3rd or higher its gives me like 22-23 psi...i checked my hosed and cleaned my boost controller and still nothin like it used to....
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From: wexford,pa
Do a search, I posted a warning to those raising stock boost. In the mitsu tech manuals it states that testing the actuator to not exceed 17psi. So since you ran like 25psi I would say you damaged the diaphram of your wastegate actuator my friend.
The only way the WGA gets damaged is if you pump more than 17psi directly into it! With a MBC or even the stock BCS, the WGA never actually see's all 25 psi. Remember, MBC's have little holes in them to vent away from the WGA so that it doesn't open when you don't want it to. Our stock WGA's start to open at something like 12 psi. Even with a MBC, it's still only seeing that 12 psi because the MBC is diverting away all the excessive boost that we don't want the WGA to see!
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From: taos county
The only way the WGA gets damaged is if you pump more than 17psi directly into it! With a MBC or even the stock BCS, the WGA never actually see's all 25 psi. Remember, MBC's have little holes in them to vent away from the WGA so that it doesn't open when you don't want it to. Our stock WGA's start to open at something like 12 psi. Even with a MBC, it's still only seeing that 12 psi because the MBC is diverting away all the excessive boost that we don't want the WGA to see!
Where did you pull that out of your ***?
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From: wexford,pa
no i didn't pull that out of my ***,
also the mbc has holes for one reason and one reason only, to vent pressure out after the spring returns to closed otherwise the actuator would stay "energized" or open.
in an mbc ( a spring and a ball) the spring and ball will keep air pressure from traveling from input to output until the set point is reached. At that point the spring is stretched to allow air to move freely from input to output. This pressure approx %100 of it will hit the actuator and open it to bypass exhaust to turn the turbine or turbo. After the pressure is lower than the mbc set point, the spring closes and air now doesnt flow from input to output. BUT air pressure is still inside the mbc to actuator, But with the holes inside the mbc the pressure is vented out. Without those holes the pressure would remain there and keep the actuator open.
also the mbc has holes for one reason and one reason only, to vent pressure out after the spring returns to closed otherwise the actuator would stay "energized" or open.
in an mbc ( a spring and a ball) the spring and ball will keep air pressure from traveling from input to output until the set point is reached. At that point the spring is stretched to allow air to move freely from input to output. This pressure approx %100 of it will hit the actuator and open it to bypass exhaust to turn the turbine or turbo. After the pressure is lower than the mbc set point, the spring closes and air now doesnt flow from input to output. BUT air pressure is still inside the mbc to actuator, But with the holes inside the mbc the pressure is vented out. Without those holes the pressure would remain there and keep the actuator open.
