Ceddymod wastegate duty cycle

[m_0ney_pit]

In ceddymods 1.9c I want to set my wastegate duty cycle so that it is always at the wastegate pressure (7-9 psi) for testing purposes. can someone tell me what values I need to change and how the stock bcs regulates boost in the ecu.

 

[mike96]

The factory BCS lets pressure bleed off from the waste gate by opening and closing the BCS at different speeds (duty cycle) the higher the duty cycle the more boost pressure is bleed away from the waste gate making the turbo work harder to compensate and open the WG. So if you want it to run WG pressure you need to zero out the WG duty cycle table so it leave the BCS closed at all time and doesn't bleed any pressure from the WG, or just run a vacuum line from the compressor cover directly to the waste gate with nothing in between.

 

[m_0ney_pit]

Ok that all makes sense I had a feeling I would have to zero the table.

My reasoning is I can get 9.5 psi with my b16g minimum with the wastegate hooked into the boost source but when I hook up the BCS it won't go lower than 18 psi.

My reasoning I want to make the b16g behave better with my setup to get a regulated 12-14 psi without going to a MBC or other boost controller so it looks like I need to rescale the stock table.

Thanks

 

[VETTE_50_TH]

You really should get a 3 port BCS like a grimmspeed.

 

[m_0ney_pit]

Its not supported in ceddymod yet as far as I know

 

[mike96]

A 3-port BCS doesn't have to be "supported" bu any method of tuning, so to speak. All that really needs to be done with it, is install it and re-adjust the WGDC table to achieve the desired boost level/s. I will have to look it up again but there are a lot of people in the Subaru forums that are using a Ingersoll Rand solenoid available from Grainger (I think it is from Grainger anyway) that is almost 100% identical to the Grim speed one only it is about half the cost.

 

[m_0ney_pit]

So the stock tables that are available for editing are max and min duty cycle which are adjustable from 0-100% and most values are 100% except for spoolup at 2500-3500 rpm which are a bit more closed 50-78% to help with spool time.

I'm going to play around with the stock valve to see how well it can regulate low boost. Just need to install my gm 3 bar and I'll report some data back.

 

[m_0ney_pit]

In case anyone else is interested in playing around with this you can log wastegate duty cycle in evoscan with address 86 and the formula is x/2 in percent.

 

[m_0ney_pit]

So I'm trying to understand what the condition is for the ecu to change wastegate position. With both min and max duty tables at 0 here is a log. It seems to work until some point but then the ecu decides to start advancing the bcs.

Attached is a log with gm 3 bar output, wastegate hooked directly to boost source no bcs connection

 

[mike96]

There may be another table that hasn't been dug up yet perhaps that is causing the ECU to actuate the BCS...