Bringing this back up as it is related to tuning drivability with cams.

Is there a decel fuel function of any sort? Maybe an RPM point that we can hopefully manipulate which will turn the injectors back on under decel. I think this might help out with the common "almost stalling" issues that people with bigger cams run into. For example, if that decel fuel RPM point is set at 1200 from the factory, bumping it up to 2500 may raise the point at which the RPM recovers - keeping it closer to the desired idle RPM value (instead of where it "catches itself" around 300 - 600 RPM).

 

ive seem to have found a way to datalog with my palm and my aem wideband....i took the white analog output wire and soldered it onto pin output #75 on my ecu (rear o2 sensor)....i then select to datalog my rear o2 sensor which outputs my wideband AFR....as a added consequence it fixed my CEL for unplugging my rear o2 sensor (i used the rear o2 sensor bung for my wideband, dont worry i have a testpipe) so yes it is possible to datalog using a palm your AFR along with RPM, Timing, etc

 

Actually it should be right under your nose.. Although a specific idle compensation or deceleration table is something I haven't seen yet, the entire area under 100% in the fuel and timing maps are "under vacuum"

At higher RPM, you'll rarely see the 10%-40% columns used except when your decelerating since engine vacuum on deceleration is higher than engine vacuum at low throttle inputs.. At idle, the 10%-20% column are likely vacuum levels higher than even stock idle.. (if you need to calculate, 1bar is the 100% column)
Its a calculated value, but below 100% I think the ECU utilizes information from the stock MAP sensor for engine vacuum...


Here's the trick though.. as idle gets poorer, the engine has less vacuum, so at idle the columns from 50% to 100% (approximately since it depends on conditions, Cams, restrictions, etc..) are where you could look to make those adjustments..

 

I forgot to comment on this because it occurred to me a few moments ago..

The EVOLink project was stalled because the developer of DSMLink didn't have the time, or resources to extract a rom for research.. Now with the ability to read/write rom files for most OBD-II compliant mitsubishis, this opens a whole new world for him.

First, he has been "Socketing" early ECU's.. But the OBD-II Eclipse ECU's (95 and later) should now be able to be read and written to (given the right bootstrap code) Someone should contact him and tell him this product exists, and let him check it out. Plus, I haven't seen any talk on extracting the ECU data and flashing the 95 and later Eclipse ECU's yet.. So he probably can contribute there..

This tool changes many things in many ways.. Since the ECU shares alot with the Evo ECU, he'd be a great resource to get to participate.

 

Already have and he is well aware of it. He even mentioned working with Colby to source the 12 pin adapters.

Eric

 

MalibuJack,

Scrappyjack was referring to the 'coasting fuel cut', which is not in the fuel tables. The Mitsu ECU will shut of the injectors under no throttle deceleration. He is asking for a table that can set the RPM to where the injectors will come back on to a little higher value.

This is a setting in DSMLink, so I know it is possible to adjust. Someone just needs to find the address/table.

Eric

 

Sweet, thats the one thing I've been eagerly watching..

 

I actually had a feeling that was what he was referring to.. We should get that table soon..

 

That would results in a lot of inconsistensy. In my case, my car switches maps even on 110oct@30psi making me loose around 20whp on top. 11.30AFR's sometimes it pisses me off . And timing gets retarted about 4 degrees and starts building again. I understand this is safety. But sometimes I think its a little bit too sensitive. Im trying to find a way around it without having to flatten the maps out. Looking for the source of it... Am I blowing spark? Is my dumptube hitting my lowerpipe creating lots of extra engine noise? Is my Knock sensor just overly sensitive? Lots of possibilities but im sure mitsu exaggerated when it came to knock safety. Didnt someone mentioned JDM evos come scaled at 550cc USDM at 513? resulting in a very rich overly safe tune.

 

Exactly. I really think that adjusting this RPM value a bit higher than stock will help out a lot with that particular aspect of drivability with 272 and "larger" cams.

 

im going to be putting in my Comps tonight i wonder how this will turn out