Troubleshooting: Manual Boost control overboost issue (Ball&Spring Type) *SOLVED*
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Troubleshooting: Manual Boost control overboost issue (Ball&Spring Type) *SOLVED*
I am having overboost issue with my 98 prelude h22 turbo. I set the boost controller to 8psi but it I floor it, it will just go higher psi and hit the boost cut. I tried to run straight line from turbo to wastegate but same , the wastegate seems not opening. I pulled the wastegate out and test it with air compressor it is working. I double checked my vacuum lines all good. My vacuum lines setup: bov to IM, boost gauge to IM. I have turbosmart mbc so the turbo compressor npt fitting goes to the T and the other side of the T goes to the wastegate ( there is an arrow on the T which manual says wastegate should be connected to it).
re: Troubleshooting: Manual Boost control overboost issue (Ball&Spring Type)
I am having overboost issue with my 98 prelude h22 turbo. I set the boost controller to 8psi but it I floor it, it will just go higher psi and hit the boost cut. I tried to run straight line from turbo to wastegate but same , the wastegate seems not opening. I pulled the wastegate out and test it with air compressor it is working. I double checked my vacuum lines all good. My vacuum lines setup: bov to IM, boost gauge to IM. I have turbosmart mbc so the turbo compressor npt fitting goes to the T and the other side of the T goes to the wastegate ( there is an arrow on the T which manual says wastegate should be connected to it).
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re: Troubleshooting: Manual Boost control overboost issue (Ball&Spring Type)
re: Troubleshooting: Manual Boost control overboost issue (Ball&Spring Type)
re: Troubleshooting: Manual Boost control overboost issue (Ball&Spring Type) *SOLVED*
What you're using is a Ball-Spring type MBC, and not a bleed-style MBC. There are some subtle differences.
These controllers still use a bleed, but the most common technique is to place a steel ball behind the restrictor hole, held shut by a spring. The main problem with this technique is that since the restrictor hole is so critical to boost, placing a free-floating ball behind it adversely affects its performance. Because the ball is free-floating, it can act like a pea in a referee’s whistle, fluttering around in the restrictor hole. This then causes boost fluctuations, and (if the spring is set incorrectly or you have a boost reference issue) boost spikes.
It's still a great controller. I'd only use this or a Hallman-ES controller if I were staying manual. But I have noticed over the years that compressor cover references as boost sources can give some seriously undesired results.
I hope that helps you understand a bit better as to the "why" of things.
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re: Troubleshooting: Manual Boost control overboost issue (Ball&Spring Type) *SOLVED*
What you're using is a Ball-Spring type MBC, and not a bleed-style MBC. There are some subtle differences.
These controllers still use a bleed, but the most common technique is to place a steel ball behind the restrictor hole, held shut by a spring. The main problem with this technique is that since the restrictor hole is so critical to boost, placing a free-floating ball behind it adversely affects its performance. Because the ball is free-floating, it can act like a pea in a referee’s whistle, fluttering around in the restrictor hole. This then causes boost fluctuations, and (if the spring is set incorrectly or you have a boost reference issue) boost spikes.
It's still a great controller. I'd only use this or a Hallman-ES controller if I were staying manual. But I have noticed over the years that compressor cover references as boost sources can give some seriously undesired results.
I hope that helps you understand a bit better as to the "why" of things.
re: Troubleshooting: Manual Boost control overboost issue (Ball&Spring Type) *SOLVED*
Again, more likely due to boost reference. Also verify that your spring used is for whatever you're looking for less than 10psi. It can also be due to retarded (conservative) timing . That can & does contribute to the issue.
There are several aspects involved with this issue. Not just the controller, or just the reference point. So you have to attack each area individually.
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re: Troubleshooting: Manual Boost control overboost issue (Ball&Spring Type) *SOLVED*
Again, more likely due to boost reference. Also verify that your spring used is for whatever you're looking for less than 10psi. It can also be due to retarded (conservative) timing . That can & does contribute to the issue.
There are several aspects involved with this issue. Not just the controller, or just the reference point. So you have to attack each area individually.
There are several aspects involved with this issue. Not just the controller, or just the reference point. So you have to attack each area individually.
re: Troubleshooting: Manual Boost control overboost issue (Ball&Spring Type) *SOLVED*
thanks buddy I was bit stupid didn’t get it from first time lol. In my case I have 5psi spring.The wastegate will read the positive pressure once it reaches 5 psi the valve should open. So if the wastegate is not getting proper vacuum it won’t work. I will work on it tomorrow starting from the vacuum source. Thanks again.
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