Yeah, 15 load (at loc_1180) sounds about like the lowest I see.

For the USDM Evo 9, the requested linear FPW is at FFFF6C30/31. This variable corresponds to the values in the input axis (aka x-axis) of the PW linearization table. Its a 2-byte value. I assume you'll know where to find it in the ROM you are tweaking. You'll need to pick a spot in the MUT table to log it. I log it at MUT 2B/2C. My EvoScan definition is:

<DataListItem DataLog="Y" Color="" Display="2-Byte Sync FPW" LogReference="2BSyncFPW" RequestID="2B" RequestID2="2C" Eval="0.008*x" Unit="ms" MetricEval="" MetricUnit="" ResponseBytes="1" GaugeMin="0" GaugeMax="66" ChartMin="0" ChartMax="66" ScalingFactor="1" Notes="" Priority="1" Visible="False" />

 

Yes, on most cars I tune I bump that load to 18-20 so it will fuel cut quicker.

Thanks for the EvoScan data, I will add it in and keep to the same request ID.
Not too sure i can work out the real address, will see how I go on that.
The car I am doing the ID2000s with is the Evo8 9653 rom currently, and may well need it for 8857 too soon.

 

Another point, on the ID data sheets, the lowest correction entry (0uS) is generally set to zero, at least for GM ROMs. I am thinking we could also zero off everything below approx 300uS as we should definitely be in fuel cut mode by then.

 

For 9653 its, FFFF8A6A/6B

For 8857 its, FFFF6BF8/F9

 

I think the zero value for GM ECUs is because GM does things differently. Not sure it would matter either way, but I wouldn't zero out everything below 0.3 ms. Keep in mind that the during fuel cut, the ECU does use this table (or the latency adder table either).

BTW, I would have bet that Mitsu used the same injector for all their Evos, but I just had a look at 8857, and the PW linearization values are much different than the USDM values which means that Mitsu used a different injector for that car. The 9653 values are identical to the USDM values.

 

Thanks for those addresses, I will put them to work soon.

The 8857 ROM does have a lot of differences to the 8858/8859 ROMs, its simpler for starters and drives nicer, less funny fueling quirks. That is some of the reasons I have switched over to it on my 9.
It also has native support for MAP and MAT without any encumbering emissions contentions, or DTCs it seems. There are many good reasons to use it.

It is also probably the base rom for the Ralliart program, so the differences you mention may be group-N related or at least performance orientated.

Maybe they just wanted looser or tighter closed-loop control.

And what did you think of the 15uS latency Base idea?

 

Do you mean change the step size to 0.015 ms?

 

Yes, change the step size to 15uS, by changing the latency base.

 

I took a look, and it would be quite easy to do. In fact, it doesn't need any recoding. Just change the step size value (apparently you call it the latency base), change the definition in ECUFlash, and that's it. Anyone can do it if they have the step size address. EDIT: The drawback is that the range of latency values is decreased. Instead of a max value of 6.12 ms, it drops down to 3.825 ms.

 

Mits call it Injector Dead Time Coefficient, which is a bit of a mouthful, Latency Base works for me as it is what they use to make the calculation.

Whatever the name, I think we can live with the 3.8mS limit ok, I have yet to see an injector that exceeds that at 9 volts or so.

The FIC1650 seems to be the one with the highest latency requirement I have seen - so far.

I think I will try this when I get back to the ID2000 car again next week. And all the other Inj tricks too of course.

 

I just enabled the 0.015 ms step size on my car. I'll get a chance later today to drive it. Curious to see whether it does anything for idle stability. Don't think it will matter for anything else.

 

sub'ed.

Would playing with this table and seeing load vs TPS help correct some still existent stutter issues? I may be in left field here but my 9653 feels like it wants to fuel cut while at very light load.

 

jeff, while your setup may benefit from tweaking these tables, I think it more likely you need to bump your 3D ISCV composite demand map.
eg the lower section, from 20 to 60, by 2-3 steps, or roughly the same percentage if you are using mrfreds xml script.

If that does not help, then I guess you could mess with this stuff a bit. Or the minimum IPW setting if you have big injectors of course.

 

Jeff, as Merlin said, I've had a bit of success playing with the min ipw when experiencing real low RPM like cut.

Are your injectors sitting on the ipw floor at idle? Or they still have a bit of movement? If they are moving, bump them up one to two settings til they're JUST sitting on the floor and see if that helps.

 

I've made a few more minor changes to the injector-related settings over the last few weeks. I'll post revised maps later this week. I also found that there is a significant lean spot that starts at about 2100 rpm, peaks at 2375 rpm, and then is gone by 2650 rpm. It happens for any range of FPW or MAF Hz, so its not the injectors or the MAF. I wrote a patch to remove it. Off boost fueling is now about as accurate as anyone could ever hope for, and I continue to remain impressed with these injectors. Could possibly be the best injector ever irrespective of fuel requirements.