You don't use the stock lines at all. No T's.

 

I had the same problem. My solution was to zero out the upward correction in the TBEC. It works well for me, and I have no worries about overshooting boost and load targets. I'll be interested to see if anyone has a better solution that doesn't require zeroing out the upward TBEC.

It is interesting that were was no boost cut with your boost limit and delay time values.

 

What numbers are the "upward correction?" Are they the 2 to 8 in the top part of the table? Do you zero those out?

8
8
8
8
6.5
4.5
3.5
2
0
-1.5
-3.5
-5
-6.5
-13
-13
-13
-13

 

Yup.

 

If I zero those out, will this make the boost @ peak more consistent? Or is this just for a consistetn load? Or is it both?

 

If you're BDEL is pretty spot on you could possibly boost less in lower gears.

Some cars have a problem like this where they overboost like that with the positive error correction #'s in, but it is very very rare, at least from what I have seen. Usually it is from too high of WGDC #'s.

 

Bryan - I used some values that you posted for WGDC - you said that it had you holding 20.5 psi.

With these values I am only getting ~15 PSI. Could this be an indication of a boost leak does every car take different numbers?

I turned up WGDC 10 units and got an increase in boost off about ~2 psi.

Thanks

 

Add my '03 VIII to the list of rare cars that does the same thing. Just like mrfred, I have the positive values zeroed out for now. There must be something we're overlooking in the ROM, or the tables don't work how we think they do. In my case I have my BDEL + offset values set below the load I'm seeing (about 10 points less) and I've never logged the ECU using the negative values.

 

Which settings did you use, what are your mods and what solenoid and/or pill size?

 

I have a GM solenoid, no pills.

Turbo Back, IC pipes, Intake, 02 Housing, FMIC.

MAP numbers from ZT2 boost sensor.



I am now using the following map.

 

What do you have in your BDEL and offset tables?

 

BDEL is 159, offset is 100.

Error correction is set to 0 across the board.

 

159 on the whole BDEL table? If you actually had Error Correction on, the ECU would be adding WGDC to try and hit that 259 load as you are barely hitting 240 without error correction on according to your calc Load in that log above at least. It's odd that you can hold 19psi with 65 WGDC all the way down. Usually you need to bring the WGDC up the higher the RPM.

First off, I would get your boost control tables actually dialed in. 159 across in BDEL and flat WGDC is not using Ecu-boost to it's fullest potential.

If you have the means, I would do a boost leak test just to take that out of the equation. Then set up your tables correctly. Should start to look something like this:



Numbers will be different for your application but the 'curves' should look the same.

 

I am just beginning to tune the GM solenoid. I plan on setting up my BDEL and TBEC later but I have zeroed it out like you suggested in another post.

I have done a boost leak test and I did not find any leaks however I did have air coming out of my valve cover (Due to valve seals I think). There for it was difficult to tell for sure if I had a leak.

I was justing wondering if it is normal to have these values in WGDC for the level of boost, this is by no means my final tune for boost control.

 

I apologize if I came off like I was saying "Dammit! You are doing it all wrong!" I wasn't sure if you knew so I was just trying to help.

For the stock turbo it's pretty close, maybe a little high. What does 65% WGDC give you PSI wise at 7000 rpm?

Do you have a full pull logged?