Megasquirt Support Forum (MSEXTRA)

Hi James.

As posted before under 3.4.2 beta 2 posts.

Please note we have come across a situation whereby the "DUTY" Base staged injection is not functioning.

This is occurring in both Batch and Semi Sequential based staging, Notably on uS Module that we're using, as we do not run the Std MS2 setups.

Hardware used is uS Module with additional hardware for Seq Fuel (PT6 & PT7) & Spark outputs (WLED & ALED).

Attached are some example MSL's of the Staging not working with DUTY based, as well as staging that is working using MAP based. So Staging in general is working but not under Duty Based

We try activating Staging via a value of 80% Duty (although we tried other values as well).

Thanks You.
working MAP Based examples to follow.

Additional MSL of MAP Based staging that's Good. (For reference)
Thank you.

You don't have the correct number of squirts for a semi-sequential setup. It should be 2/sim (or 4/alt). With the wrong value, the duty cycle is not correctly computed internally which is why staging won't work properly.

Jean

Hi Jean..

ok... So semi-seq staging with my current settings no good... Cool.. I'll double check

What about the Batch Based Staging... it also didn't work.. or am I missing something there as well?

If there is a problem that it won't calculate correctly at 1 squirt, could someone please UPDATE the Tooltips etc. in the ini file and LET Everyone know, as grenading a $20K engine is an expensive way to find out.

Kindest Regards
Gordon.

I don't know how your duty staging will work in reality, even if it did trigger properly.
I saw on the MSQ you had 85% duty staging with 5% hysteresis. I have 630cc primaries and 630cc secondaries and I stage from TPS and MAP. When I stage my PW and Duty both halve in about 0.1S. That is usually dropping from something like 60% duty to 30% duty from my 50/50 injector split. You have a 40/60 split so from 85% duty I would expect you to drop into the low 40% on staging. I do not think 5% hysteresis is going to work when you drop 40+.
I have had no issues with using TPS primary and Map secondary staging.

Duty-based staging uses the calculated primary duty without the stage to determine if it should stay staged. It will work fine.

Ah good to know, I thought it was real duty.

Hi Guys...

Yep to confirm as Jean said...

DUTY Staging DOES NOT work with 1 Squirt per cycle...

in either Batch or Semi-Seq...

Tried it on the bench..

Now how would we work around the LARGE injector pulsewidth problem at 2 Squirts...
Actual Injector sizes running on the vehicle are 900cc Primaries & 1600cc Secondary. Full 100% (98% actual) Ethanol @ 2.6Bar Boost..

Thanks Jean.. & Slow_Hemi6 for your assistance!

PS.. I never even thought that the Squirts/cycle would be an issue, pity though... Maybe something to look at in the pipeline.

Gordon.

It is a shame you didn't post up the MSQ/MSL a few weeks back before 3.4.2 was released.

Investigating, it looks like the code has behaved like this for over five years ?? (3.0.x firmware)

James

Wasn't there some talk, waayyy some time ago, about changing the code etc to basically ignore the 'alt/simult' and 'number of squirts' settings for seq and semi-seq, since the only valid options are '1' and '2' respectively, and 'simultaneous' in both cases?

dontz125 wrote:Wasn't there some talk, waayyy some time ago, about changing the code etc to basically ignore the 'alt/simult' and 'number of squirts' settings for seq and semi-seq

MS3 handles this differently. However, as MS2/Extra is now at a mature stage in its life, I am reluctant to make a change like that when the code is overall known to be working well.

James

I've made a fix and am just working with Jean on some tooltip enhancements for semi-seq before I put out a new beta.

James

AWESOME!!!!

Thanks James!!..

Done some bench testing of the Staged feature in MS2 extra 3.4.2 now, and also tried the 3.4.3 Beta, trying to figure out how this stuff works before settings it up on my new drag race engine.

I have found that the "Table" does not work in semi sequential mode while using additional drivers.
PW#1 does what it's supposed to do, and the same with PW#3 & 4 (secondary injectors), but PW#2 tracks the PW#3 & 4 values instead of PW#1.
They alternate as they should though, and it all works fine in the other modes such as RPM, TPS, MAP etc, and also when in 0 and 100% in table mode, just not any value in between. This renders the table function useless in this particular case.

And another thing I find a bit weird: Since MS2 only have two DC% indicators (DC1 and DC2), would it not be logical that DC%#1 is for PW1/2 (primary injectors), and DC%#2 would be for PW3/4 when running additional drivers in staged mode?

The attached pic. shows what I'm talking about when in table mode running additional drivers and semi-sequential and the table cells are set to a value != to 0 || 100.