I have a GM 3 Port setup with modified MWDC to get 20 psi. If I make a third gear pull from 2K RPM I get rock solid boost to 20 psi (at 3rd or 4th gear). But when I am cruising at 4K RPM with no boost and floor it I get a spike of 22 psi and then goes again to 20. This happens at any rev over 3500. Is there any way to get rid of those mid throttle to full throttle overboost spikes. Now it is not too bad but eventually I want to set up to 22 psi and if I get the same behavior I would get a spike to 24-25 which might be too much for my car. Any recommendations?

 

Post your boost maps. Sounds like you need to dial everything in a little bit more.

Post:

1. Turbo Boost Error Correction
2. Boost Desired Engine Load
3. Max Wastegate Duty Cycle
4. Variable for Boost Control
5. WGDC Correction update delay

Sounds like the additive error correction is kicking in.

Also, logging WGDC, WGDCCorrection and Boost Error will give you a much better idea what is going on during this as well.

 

I am starting on ECU Boost Control (less 1 week of testing) . Right now I am not using any correction and I am making all the logs at third gear. I have not added the Variable Boost Control and WGDC Correction update delay tables. Here is a log with my current setup and the boost maps.



Does the RE/deactivate maps above works with an EVO 8 ECU?
Thanks a lot for your help

 

Well I did some reading and testing last night and today and added the following to ECU Flash

- WGDC Correction Interval #1
- WGDC Correction Interval #2

I am planning to use 3 as the interval after I fill the correction tables.

I also added the Solenoid Re/De Activation definitions (I was seen the 100% DC at 7500 RPM) but I am not getting the 7500 as default. When the definitions was added I got the values on the image below:

Do I have something wrong? It is not 7500 as default.

What I used was:

 

you are running 100% WGDC for too long. start backing off WGDC around 2000 RPM.
Here is mine and the boost curve that goes with it. Mind you i still need to clean it up and add correction.

 

Why is that bad. At 2500 RPM you are only seeing about 10 psi so it is still ok to run 100%. The boost peak is at over 3K RPM and ust before that (i.e. 2750) is where you need a low DC. I have not receive my JDM Map yet so I am uwing 2 byte load to tune my WGDC

 

Edit my bad i didn't read the original post i assumed it was in a WOT pull not cruising.

 

One thing to keep in mind is that the 03-04's run 100% WGDC at idle and cruise until you go WOT. The 05+ run 0% WGDC at idle and cruise until you go WOT. You can see this by logging WGDC.

03-04 example:



10 is 100% on that graph

05+ example:

 

Thats weird, on my 2004 EVO 8 I got 0% WGDC at idle. I just look at my log and after the pull I press the clutch and when the RPMs were at 900 I got 0% WGDC.

Either way I guess that should not be a problem. Anyway, Do you have any recommendation on my maps for the mid throttle overboost. Also, Do you know the address for the Solenoid De/Re Activation for the VIII, I have a 04 EVO 8 with ID 96420008 and I am using the lines below for the Solenoid De/Re Activation:

But I do not have 7500 as default so I am not sure if I got a wrong address. The image is on post #4

 

I just took a look at my log/rom database and you are right, 96420008 runs 0% WGDC like 05+