RomRaider

The 16bit ecus are limited to about 300 g/s airlfow, but I'm pretty sure I can overcome this limitation by changes to the code. This has already been done by Subaru on a particular JDM STi rom where the "cap" is raised to 400 g/s. I don't know how much interest there would be in this feature, but if there is enough and some willing testers, I'm pretty sure it can be accomplished. Here's how Subaru did it:

1. Rescale MAF table for 400 g/s max.
2. Change constant involved in calculating engine load from airlfow so that engine load will be accurately calculated given the new MAF scaling.
3. Update any comparisions involving airflow. These are conditional branches in the code involving a constant. Constants are changed so the relative comparison remains the same.
4. Change SSM MAF logging parameter conversion so that airflow will be reflected accurately in any logger.

In addition to the above changes, we would need to use a different conversion for MAF scaling in the ecu defs.

It perfectly works this way Tested and approved !

There is also the OBD constant to rescale or logging will be wrong if not using SSM.

So, you've modified your rom in this way?

FWIW, I think you've found the right stuff. There is a hard-coded constant that can be used to translate the available bits across a wider output range. That's the core fix. Then other maps need to be adjusted for the new scaling. I think that is mostly an XML issue.

This raises a new issue. How will we deal with the MAF scaling table definition if there are two possible scaling factors for it?

Count me in for testing. Let me know when what you need from me.

We'll need this functionality anyway for per gear and LC stuff. What would work is to check for a particular subset of the code (or changes) in the rom that would indicate if the table should be visible or not. So, if the rom has the per gear code, then the per gear tables will be displayed. If the rom has the particular modifications for the maf limit, then table #2 (with the 400 g/s scaling) will be displayed, while table 1 will not.

Off topic, but we really add some scrolling capability for tables like MAF scaling, instead of the table being split into 3 separate tables.

I have been looking forward to this, so count me in for testing. I just swapped out my TD05-16G (which maxed out the MAF) with a FP Green this afternoon (3 inch intake, 8cm hotside) so I am stuck with SD mapping with the UTEC for now.

Upping the MAF limit would be an awesome feature!!

If you would like to volunteer to test, you'll need to meet the following requirements:

1. You are using one of these ecu revisions - (A4SGE01C, A4TC400L, A4TF520F, A4TF800F).
2. You must have a wideband o2.
3. You have enough power where this feature would be useful to you and could be tested thoroughly.
4. You are experienced with a logger including logging wideband data and know how to tune.
5. You know how to switch ecu definition files with the ecu definition manager in RomRaider.
6. You are willing to assume 100% of the risk.

PM me your rom if your are interested.

I might suggest you change the CALid, say, A4TC400L becomes A4TC401L, or maybe ENGI400L, etc. This would include all the Enguinity custom code changes.

Yes, done this way

I would love to help you test, but at this time I am breaking in my new 2.5L. I am almost certain I will be able to max out the MAF with this setup (8cm 18G), but not for another 400 miles unfortunately.

That's a good idea.

Yep. I'll think about it some and post my ideas in the definition forum.


We'll have it in the next release.