Ah I see, thank you so much!!

 

Are there any tuners in florida utilize ECU-based direct boost control v/ the tehpra mod?

 

4 wheek slide is located in Florida. You can also try Mellon Tuning.

 

Bump for it, just for info

 

I'm using the JDM MAP & a pill-mod to control boost. I've got my WGDC dialed in for 24lb from spool to redline. It's still needs some more tweaking, but it's getting close:



In my car a 2nd gear pull lasts about 2-3 seconds, so with the correction interval set to 1, the ECU has about two opportunities to apply corrections (=not much). Based on that, I'm trying to dial in the WGDC to get as close to desired as possible for 2nd gear pulls, and then use the correction tables to tune for the higher gears.

The problem I've run into is that the BoostError logged in EvoScan isn't always right. My boost target is set to 24 psi from 4k rpm to redline, in the logs I see stuff like this (RPM, Boost, Error):


3,719 19.16 -3.09
3,875 24.77 -1.54
4,156 25.35 1.44
4,625 22.65 -1.06
4,969 23.81 -0.68
5,344 25.35 0.09
5,688 24.58 0.67
6,031 23.61 -1.06


On the 2nd point (3875), the error is negative when boost is 24.77 psi, all the other points are fine though. Anybody know what's up with that or how to fix it?

 

No way to fix it, error correction and the changes it makes lag behind boost. Especially on spool-up because it happens very quickly.

 

thanks for the reply, but you misunderstood my question. The problem is not with the error correction, but the BoostError value (as reported by EvoScan). Since boost is above 24psi (the target) @ 3875rpm, the BoostError should be positive, but it shows as negative, which is obviously wrong. .

To me that says there's a problem with the way BoostError is being calculated within the ECU, or how it is being reported by EvoScan)?

 

I've never had that issue. What entry are you using for evoscan?

These?

<DataListItem DataLog="Y" Color="" Display="Boost Error" LogReference="BoostError" RequestID="8A" Eval="0.0241*x-3.087" Unit="psi" MetricEval="" MetricUnit="" ResponseBytes="1" GaugeMin="-5" GaugeMax="5" ChartMin="-5" ChartMax="5" ScalingFactor="1" Notes=""/>

<DataListItem DataLog="Y" Color="" Display="WGDC Correction" LogReference="WGDCCorr" RequestID="8B" Eval="0.5*x-64" Unit="WGDC%" MetricEval="" MetricUnit="" ResponseBytes="1" GaugeMin="-50" GaugeMax="50" ChartMin="-50" ChartMax="50" ScalingFactor="1" Notes=""/>

also, what is your boost adder and what is your local atmospheric pressure?

 

I'm using the same definitions as you showed. The question about the boost adder is interesting though. I'm using 14.7psi (sea-level) and according to the weather service it was 14.61 psi this morning when I logged the data. Doesn't seem like enough to account for what's in the log, but that was a good idea.

 

I do understand your question. It happens because your boost changes faster than it recalculates the error. (e.g that error may have been calculated 20ms before when the boost was 21psi.)

 

sorry, I guess I misunderstood your answer . Nothing much that can be done is this case ... should I be logging ECULoad to make sure the ECU isn't overloaded with a 1 sec error correction interval?

 

FYI, the first set of posts note that the correction interval is roughly equal to .08-.1s per pass-through. So over 2 seconds you have roughly 20-25 corrections occurring.

Also, regarding your last question... ecuload is related to the "load" of the engine, not the processor in the ECU.

 

yes was about to say, 1 in the interval setting isn't 1 sec it's .1sec

If you visually plot the boost error at the default 10 , 5 and then 1 you will see just how fast 1 updates compared.

 

Hows it goin guys. Mr.Fred thanks again for your work seems like I'll using it to tune my new direct boost control system in a few days.

My HKS evc just **** the bed on me and I cant get anymore than 11 psi out of it. It was limiting me to 25 psi until I adjusted my wastegate and I got 27-28 psi out of it.

I was going through all the directions and looking at my BEC table here

I for some reason have messed up values instead of your scale.

Would you by any chance know what I did ?

I did add the mut address's seeing I have the mut table I just changed them there. I went over everything also and it all seems right but who knows.

 

I'd double check you added the proper definitions to the xml files, along with the proper scalings.

Did you add the following?