Hmm, in looking at the Z-chip webpage, they do apparently tweak the MAP sensor signal to affect performance. I guess the MAP sensor does play a role. I'll have make that a priority in my examination of the Evo X ROM.

 

While I'm no assembly language pro, if there is any way I could help out in this process, I'd be more than happy to. I'm personally really interested in the relationship between the ECU and the SST on the MRs/Ralliarts.

 

I'd imagine the MAP sensor is used to measure boost in the plenum, and therefore give the ECU the info it needs to regulate the turbo wastegate. You agree?

 

Not actually, the wastegate duty cycles are adjusted in accordance with load and RPM. It doesn't take MAP readings to adjust the boost control solenoids.

 

Wouldn't it use load and RPM to determine the necessary amount of boost, and then use the MAP to verify the boost?

I don't see how it could be a good idea to indirectly measure boost.

 

Mitsu has a history of doing odd things with their boost control systems.

On the 8/9 boost load from the factory follows a load that changes with temp. It will give you more boost when its warmer and less when it is cooler, until you change the load address it follows.

mrfred did write a patch that allowed the 8/9 to use PSI-target boost (using the 3 bar map sensor) instead of using Load-target boost. I'm sure that will happen again with the 10. Right mrfred.

On the 10 there is a very large MAP reference table that the 8/9 does not have. I would assume it is a check reference table or something, I am sure mrfred/gunzo will find out soon enough.

 

Evo X direct boost patch? What's that?

Do you have an address for the large MAP reference table for any of the Evo X ROMs?

 

 

0x60454 for the table .. you should be able to jump in from the pointer to the subroutine ..

Its a 16bit table ..

 

It does make sense to provide more boost in the summer than in the winter in order to keep power output consistent throughout the seasons, though it may be less efficient due to higher intake charge temps (has to cut timing, or give more fuel).

Do any of you think it might be possible that the rich mixture throughout the fuel maps is due to mitsu being "better safe than sorry" should their car be driven on very hot days?

I was also wondering if it was possible that mitsu might be opening the throttle all the way on cruise, and use the wastegate to maintain a specific airflow. The benefit would be less stress on the turbo (and since it would be spinning slower, the charge would be cooler as well). The big negative here would be sluggish immediate throttle response because the turbo would have to spool up further (not a big deal when cruising, right?). I don't know. Just a thought.