[SOLVED] WasteGate Duty Cycle not effecting boost

Scaytale

Scaytale

Gold Member
Good Day all,
2013 Speed 3, 2.5 bottom end with 2.3 head.
The Set up
Autotech Fuel Pump Internals
Cobb Access Port
Cobb airbox
Cobb Intake
Cobb Downpipe
Corksport Recirculation/Bypass Valve
Corksport SS Exhaust Manifold
Corksport Boost Control Solenoid
Corksport CST4 Turbo
Corksport Rear Motor Mount
Corksport Injector Seals
Corksport Front Sway Bar
CPe Top Mount Intercooler, similar to the Corksport Top Mount
Large hood scoop

Background
This was the Daily driver for years. No big power stuff, just basics and no more than about 20 PSI.
Spun a bearing in the 2.3 and swapped to the 2.5 bottom end.
When I did this, I reverted to the Stockish tune, with adjustments for 3.5 MAP and slightly larger displacement, and zeroed out the WGDC, and Boost Targets, left the Boost Throttle close at 17 PSI and Fuel cut at 18 PSI. I already know that the boost controller Spring pressure is ~15 PSI. Tested when I first installed, I could get ~14.5-15.25 PSI. (I’m using Pure Boost tuning right now)
Been redoing the MAF Scale, got that done and it seems that the fuel tables were still good.
Put in the boost targets, essentially the stock boost + 1 PSI. so ~ 16.5 in the middle of the RPM band tapering to 14.75 at 6500 RPM Increased Throttle Close to 17 PSI and Fuel Cut to 18 PSI Added WGDC low numbers to work up to boost targets. All seemed to go well so moved up to essentially the Cobb Stage 1 boost levels were next. 18 PSI, throttle close at 19, Fuel cut at 20

The Issue

I have been raising the WGDC based on the results of WOT boost runs and right now just the basic rule of thumb of raising (or lowering) WGDC by the percentage difference between commanded boost and actual boost. While at first it seemed to make a slight difference (up to about 17 PSI), as I continued to refine the WGDC the changes to actual boost have stopped increasing with increased WGDC, it seems to not really do better than ~ 17 PSI (Spring pressure is ~14.5-15.25 PSI)
WGDC is a lot higher than it was before (80 @ 3500 tapering to 75 @ 6500 and 70 @ 7000)
It seems that while the Actual WGDC tracked closely to the commanded WGDC in the beginning, in the last set of runs the Actual WGDC didn’t increase when I raised the commanded WGDC.
So before moving this up any more I, started looking for issues.

What has been done and verified.

Boost Leaks, none found
Boost Control Solenoid Hoses, all new high quality
Boost Control Solenoid Hoses hooked up correctly, checked double checked and checked again
Boost Control Solenoid operation, as best I can tell with 12 volts and Mighty Vac, seems to be fine, and not that old.
Took the Boost Control Solenoid out of the equation to make sure that the Turbo and Waste gate canister were operating as they should and it seems fine.
Put the Boost Control Solenoid back in the equation and checked that the hoses were in the right place again.
In the tune file, all boost based (plan for hybrid tune later) all load tables zeroed out.

Really hoping I am just missing something in the tune file.
 
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Is the turbo IWG or EWG? Have you checked for cracks in the turbine housing near the WG swing valve where it seals to the housing if it's IWG?

There could be other limiting factors such as tune etc. If you're trying to do target torque VS target boost it might limit boost because you're hitting the required boost in order to hit tbe required power.

Post a log and a tune file you're running so we can look at it.
 
Because I couldn't think of anything else to try;
I loaded a Cobb OTS map, updated for my MAP and MAF, also the limits.
Everything else I left the same, I believe this should have meet the boost commanded or maybe even fuel cut as I did NOT reduce the WGDC for the Corksport Boost Control Solenoid running in Interrupt mode.
However, that wasn't the case. Lower Boost and WGDC, still not hitting the commanded WGDC.

Thanks for checking it out for me.
 

Attachments

By default, the ECU wants to run a load tune. If you don't *completely* remove all load corrections, it will adjust.
You've also increased displacement (I daresay this wasn't a super great idea on a stock head), which increases the amount of air that the engine will flow for a given PSI.

Remember kids, boost and flow are *NOT* the same thing.
 
Enki said:
By default, the ECU wants to run a load tune. If you don't *completely* remove all load corrections, it will adjust.
You've also increased displacement (I daresay this wasn't a super great idea on a stock head), which increases the amount of air that the engine will flow for a given PSI.

Remember kids, boost and flow are *NOT* the same thing.
Click to expand...

If I am missing something in "*completely* remove all load corrections" please point them out.
I'm good with Criticism, that is productive.
I also understand that boost and flow are not the same, however, it is Only 200cc, I understand that flow increases with RPM, I believe that this is well within the available flow of the Stock Mazdaspeed 3 head. Please, if you have information to the contrary present it.

It seems the issue is that the ECU is not allowing commanded WGDC.
I have commanded a WGDC in the 90's and still the actual WGDC logged is in the 60's.
Maybe I don't have all the LOAD tune stuff out, but if that is the case I would appreciate it if someone would point out what I am missing.
I have attached a file, that shows the Log results from the Modified OTS file loaded above.
It seems to show that increasing the WGDC DOES increase boost, However the Actual WGDC is substantially less than the Commanded WGDC. On average ~ 30% Lower than what is commanded.
The "New WG" is based on a basic 4% (or points) per PSI boost, not the best way but trying to get in the Ball park or show a trend.

Thanks for checking it out.
 

Attachments

I don't have ATR installed anywhere to check your map, but I can say the only other things that can mess with WGDC directly are boost limits, fuel cut and throttle close limits, load limits, and the injector offset limit (which is, iirc, .2 or an IDC limit of 80% or somesuch).

Shouldn't take long to re-check all the tables for anything that references load or fuel or other limits.
 
Enki said:
I don't have ATR installed anywhere to check your map, but I can say the only other things that can mess with WGDC directly are boost limits, fuel cut and throttle close limits, load limits, and the injector offset limit (which is, iirc, .2 or an IDC limit of 80% or somesuch).

Shouldn't take long to re-check all the tables for anything that references load or fuel or other limits.
Click to expand...

Thanks I will check it out again.
What are you using instead of ATR?
I know there are other applications, just wondering what others are using now that you can't download or get updates to ATR

Easter Bunny said:
200cc is still 8.6% not inconsequential
Click to expand...

Enki said:
*228cc

Edit: *10.08% increase
Click to expand...

I agree, Not inconsequential, that's why I re-did the MAF, the changes were not large but they did cover a about 3/4 of the table, I would have to look to see what the percentage change was. I'm pretty sure I have the old tune file.
my comment was that, I didn't think the 10.08% was enough to make the cylinder head a restriction to flow.
I could be wrong, but I haven't seen any evidence.

I tried using a pure boost OTS COBB tune, modified only the MAP, MAF and Limits to match what I have and ASSumed that would mean that any Load items would be disabled. However I know it is an ASSumption.

I will go through the tune file again and see If I can find anything at all.

Thanks for the input
 
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I use Versatune.

Scaytale said:
...I didn't think the 10.08% was enough to make the cylinder head a restriction to flow.
I could be wrong, but I haven't seen any evidence.
Click to expand...

Historically, all power gains are made from head and cams; the turbo is just a multiplier. I went the other way with my build to a 2.0 (1999cc, specifically); the head can only flow so much per revolution, and going bigger bottom end with no headwork or cams means you're trying to fill a larger cylinder in the same amount of time... Your VE has dropped very sharply past probably 4,000 RPM while allowing for significantly more airflow than normal below that. Essentially, the restriction to flow was already there, you just amplified it with the 2.5 bottom end.

Despite this, it's still still flowing more air than you realize because the boost is there and air is still flowing. The simplest thing you can do is recheck all the tables in ATR one by one to see if any have anything to do with load/boost/fuel limits and go from there.
 
Scaytale said:
Really hoping I am just missing something in the tune file.
Click to expand...

Got my Wish :D Because I'm not using my Brain.
I missed something in the tune when I redid the MAF, didn't even think about the weather conditions or even why this would be like it is.

Didn't consider that the Outside Temp had dropped a little more than 20 deg to the Low/mid 50's
IAT 2023-12-12 161254.jpg IAT_2 2023-12-12 161254.jpg
 
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