Boost gage/controller questions
Thread Starter
Drifting
Joined: Oct 2000
Posts: 1,396
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From: Sacramento CA
Boost gage/controller questions
Anyone have a GReddy PRofec B-spec II. I have read the instruction book the guy I bought the car from sent with the car. It makes no sense with what he said. I want low boost set to 6lbs and high boost set to 12-14lbs for now, Maybe I am not smart enough to get this, but I did graduate college.
Thanks,
Jeffy'
Thanks,
Jeffy'
Instructor
Joined: Jul 2004
Posts: 227
Likes: 6
From: Houston TX
Hi Jeffy
The short answer is that you cannot simply dial in "14lbs". The SET percentage is a duty cycle for the solenoid valve and not a pressure sensor.
What are the ratings of your waste gate springs?
This will be the lowest boost available for your system.
The Set control will dial in a boost level by adjusting the duty cycle of the solenoid valve. You will be able to adjust the boost between the waste gate spring lbs rating and the maximum attainable by the system (whatever scary level that might be).
i.e. a setting of 0% will give you the lowest boost level available (i.e. waste gate spring boost)
A setting of 100% will likely destroy you set up in short order.
You need to gradually increase the "SET" percentage until you get the boost you want.
You should also pay attention to the Gain setting. It can be adjusted to provide the fastest response but without spiking.
Hope that helps.
The Greddy has worked well for me and has been simple to set up.
and here is a link http://splparts.com/doc/tech/EBC.htm
The short answer is that you cannot simply dial in "14lbs". The SET percentage is a duty cycle for the solenoid valve and not a pressure sensor.
What are the ratings of your waste gate springs?
This will be the lowest boost available for your system.
The Set control will dial in a boost level by adjusting the duty cycle of the solenoid valve. You will be able to adjust the boost between the waste gate spring lbs rating and the maximum attainable by the system (whatever scary level that might be).
i.e. a setting of 0% will give you the lowest boost level available (i.e. waste gate spring boost)
A setting of 100% will likely destroy you set up in short order.
You need to gradually increase the "SET" percentage until you get the boost you want.
You should also pay attention to the Gain setting. It can be adjusted to provide the fastest response but without spiking.
Hope that helps.
The Greddy has worked well for me and has been simple to set up.
and here is a link http://splparts.com/doc/tech/EBC.htm
Last edited by DanTTVette; Feb 27, 2007 at 10:03 PM. Reason: added link
Thread Starter
Drifting
Joined: Oct 2000
Posts: 1,396
Likes: 0
From: Sacramento CA
Ok it is a little clearer
Maskell,
I believe my waste gate springs are 5lbs at least that is what Lingenfelter puts in. The pervious owner up graded some other parts so who knows.
Anyway so basicly as you up the % you are tightening the spring so it doesn't blow off as soon. If I have that right. Lets talk gain. So you keep upping until you get a spike? Is a spike a big jump on the gage whereas it should be a smooth rise?
Thank-you for your time,
Jeffy'
I believe my waste gate springs are 5lbs at least that is what Lingenfelter puts in. The pervious owner up graded some other parts so who knows.
Anyway so basicly as you up the % you are tightening the spring so it doesn't blow off as soon. If I have that right. Lets talk gain. So you keep upping until you get a spike? Is a spike a big jump on the gage whereas it should be a smooth rise?
Thank-you for your time,
Jeffy'
Instructor
Joined: Jul 2004
Posts: 227
Likes: 6
From: Houston TX
Jeffy
Prettty much "tightening the springs" is a way you could describe it.
The result is similar.
As you up the SET percentage you are slowly "blocking" or removing the boost from the waste gate.
The solenoid acts as an adjustable gate between the springs and the boost at the manifold.
So instead of it taking 5lbs of boost to open your gates, the system needs to generate more boost to get past the solenoid and pressure the gates open.
I think the link in my first response talks about "Gain" pretty well.
A boost spike is just as you describe it.
You are going to up the SET% to get to the boost level you want.
You are going to up the GAIN% until you get the most responsive curve you can but without over shoot.
Dave
Prettty much "tightening the springs" is a way you could describe it.
The result is similar.
As you up the SET percentage you are slowly "blocking" or removing the boost from the waste gate.
The solenoid acts as an adjustable gate between the springs and the boost at the manifold.
So instead of it taking 5lbs of boost to open your gates, the system needs to generate more boost to get past the solenoid and pressure the gates open.
I think the link in my first response talks about "Gain" pretty well.
A boost spike is just as you describe it.
You are going to up the SET% to get to the boost level you want.
You are going to up the GAIN% until you get the most responsive curve you can but without over shoot.
Dave
Maskell,
I believe my waste gate springs are 5lbs at least that is what Lingenfelter puts in. The pervious owner up graded some other parts so who knows.
Anyway so basicly as you up the % you are tightening the spring so it doesn't blow off as soon. If I have that right. Lets talk gain. So you keep upping until you get a spike? Is a spike a big jump on the gage whereas it should be a smooth rise?
Thank-you for your time,
Jeffy'
I believe my waste gate springs are 5lbs at least that is what Lingenfelter puts in. The pervious owner up graded some other parts so who knows.
Anyway so basicly as you up the % you are tightening the spring so it doesn't blow off as soon. If I have that right. Lets talk gain. So you keep upping until you get a spike? Is a spike a big jump on the gage whereas it should be a smooth rise?
Thank-you for your time,
Jeffy'
