Just for the sake of clarity; this is not needed if you convert over to SD?

 

Great. I was just thinking the other day that this needs to be done.

 

You are asking a question right? Not making a statement? Just wondering cause it looks like a statement.

 

I'm pretty sure the question mark is a dead give away

 

I would imagine the load limit is still in effect if you switch over to SD. When I switched over my load decreased by about 10, that's all. I am using the JDM 3 bar sensor. But if you switch over the 4 bar omni sensor, that will dramatically lower your load values and the limit should not be reached. This is because of the scaling of the 4 bar sensor.

mrfred am I correct in my assumption?

~Zach

 

So I guess the higher the BAR rating of the sensor, the lower the scaling for the same power level car?

 

Yes from my experience that is correct. It makes sense.

 

It doesn't really matter what MAP sensor you're running; when you convert to SD you dictate what you want your load to be for a give pressure. For me; I'm running a 1:1 value over 100Kpa. I'm pretty sure I remember reading that once you go SD it removes the load limits associated w/ the MAF based setups. I used to have the load limit/IPW limit removed on the MAF setup w/ a patch from JCS that I had to set back to stock values once going SD.

And yes, it was a question in the form of a clarifying statement hence the question mark

 

Yeah I am not sure then, mrfred or jcbanks would know 100%.

 

Found what I was looking for:

https://www.evolutionm.net/forums/7301160-post186.html

 

Some clarification is in order:

1) A properly tuned SD setup will show exactly the same load values as the original MAF setup. That is the goal of the tuning process after converting to SD. This is true regardless of the MAP sensor that is used (e.g., 3-bar, 4-bar, 5-bar, etc).

2) The MAF algorithm includes code to *clip* the load value. If the load calculated from the MAF exceeds the clip value, then the algorithm will use the clip value. That code has nothing to do with the load limit tables I have posted here.

3) The load limit tables I have posted here will cause fuel cut to occur when the load, calculated either from MAF or SD, exceeds the value in the table (and the delay time has passed).

 

just got mine sorted hope to try it later.

 

I think what they were trying to say was that when going to SD, you can fudge the settings so the maximum load you hit can stay under the 319 load limit. I know the old school MAFT guys did this so they had maximum resolution with the factory ECU scaling since it wasn't able to be edited by the averge user like we can so they were forced to make their peak load stay within the factory map scaling.

I agree that its best to match the MAF scaling since we don't REALLY need to fudge the max load values reached with SD. Unless of course you're running insane loads and the amount of load scaling steps we have available (its around 20 load points right?) doesn't offer enough resolution, then it would make sense.

 

Fudging an SD tune so that load reads below the real value is a really bad idea. I think it would create more hassles than any benefits it would provide. Now that we have much better control over the ROM programming, no one should be doing that.

 

Just out of curiosity, is it possible to add load columns to the fuel/timing maps for the guys now pushing serious loads on street cars? Thats one of the only major differences between the AEM guys and the stock ECU's guys these days.