MS1 Soft cut and hard cut relations

[RuneDK]

While dynotuning yesterday, the tuner and i talked about how the softcut behaves in relation to the hard cut.

Lets set an example (figures choosen for easier understanding):
Soft cut 5000, retard to 5degrees BTDC max soft cut time 0.5sec
Hard cut 6000

The car is driven WOT through 3rd gear. Reaches 5000rpm, goes into softcut and retards to 5degrees BTDC.
Max soft cut time is reached at 5300rpm - what happens now?
Does it go directly to hard cut at 5300, or does it go back to ignition table, and pull through to hard cut at 6000?


Another example:
Soft cut 5950rpm, retard to 0 degrees, max soft cut time 5sec
Hard cut 6000 (spark cut).
Car is driven WOT through gear, and reaches 6000 rpm.
Will the spark events ocurring for the next 5 seconds at <5950rpm happen at 0degrees? Meaning, will the spark events in spark cut mode happen at 0degree TDC for the time specified in max soft cut time?

[jsmcortina]

What/where is the "max soft cut time" ?

James

[RuneDK]

I am sorry. By soft cut max time, i meant soft limit max time(s). See attachment.

What I am asking is, as an example; if hard rev limit(rpm) isnt reached by the end of the timeout set ind soft limit max time(s), is soft rev limit then disabled and it goes back to running of ignition map again, or does it go straight to hard rev limit, even though hard rev limit rpm isnt reached?

And if i have soft rev limit set at 5950, soft limit max time(s) 5 seconds, soft limit absolute timing(deg) 0degrees, and hard rev limit at 6000 (using spark cut), will both limiters be activated, so that if i bounce of the rev limiter for a given time, here set to 5 sec "timeout" on soft limit, and not going under 5950rpm, then i will have absolute ignition timing of 0 degrees for 5 second, while still implementing my hard cut which in this case is set to spark cut only?

Hope I am making my self understandable at this late hour (here in denmark)

I've booted megatune to have a look at the help index regarding:

The soft rev limiter is for spark based codes, this retards the ignition to the
Soft Limit setpoint to reduce engine power and to try to reduce engine speed.
If the soft limit point is maintained for the limiter max time setpoint then the
hard limiter will cut in. This will also come in when the RPM reaches the Hard Limit setpoint
the hard limiter can be used in fuel only mode or in spark modes

This answers my first question actually, setting soft limit to 5000rpm and soft limit max time to 0.5 sec, and hard limit to 6000, then it will hard limit, regardless of reaching the hard limit setpoint of 6000
Second question was, if given enough timeout on soft limit max time, will the two limits be active at the same time, if set closely enough, like soft 5950 and hard 6000?


Reason for my question is, i'm making a car that should be able to draw attention at events. I'm looking for a serious fireworks show, and havent been able to reach it through only spark cutting, regardless the settings of cutting x of y, and even adding a hefty amount of fuel at last loadcells.
Thats why i would want the limiter to take the ignition to TDC, or even ATDC if needed.

[Siris]

Why don't you do a dual map, and use the secondary map with a serverly retarded spark map and loads of fuel.

Car runs normal, push fireworks button and all hell breaks loose.

[dontz125]

<Ob pedantic> Dual map and map switching are very different things; dual map runs two fuel maps concurrently, VE1 on injector bank 1, VE2 on injector bank 2. Map switching alternates fuel (or spark) maps based on an input; VE1 (or spark 1) when the switch is off, VE3 (or spark 2) when the switch is on. Note the difference in the numbering of the alternate maps between fuel and spark.

That said, your comment about fuel and spark maps set up to cause a show still stands!

[Siris]

<Ob pedantic> Dual map and map switching are very different things; dual map runs two fuel maps concurrently, VE1 on injector bank 1, VE2 on injector bank 2. Map switching alternates fuel (or spark) maps based on an input; VE1 (or spark 1) when the switch is off, VE3 (or spark 2) when the switch is on. Note the difference in the numbering of the alternate maps between fuel and spark.

That said, your comment about fuel and spark maps set up to cause a show still stands!

Proper vernacular, my apologies sir. You are correct. I'm coming from an aem fic, which called "map switching", dual map.

[RuneDK]

Disregarding the last posts;

Still asking;
Will running 2sec soft rev limit max time, soft rev limit 7450, soft limit absolute timing 0 (or -5), and hard rev limit 7500 result in the sparkevents occuring during hard cut being at 0 (or -5) absolute ignition timing, or will the soft limit disengage as soon as hard limit engages?

[RuneDK]

I actually just found a dusty megastim i remembered i had, so i took out an old 2.2 board and played around with it. Soft limit absolute timing WILL be implemented, AND kept during hard limit. Let me set an example:
Setup rev limiter to spark cut.
Set soft limit rev to 3000, soft limit advance to 0 degrees, and soft limit max time to 1 second. Set hard rev limit to 4000 rpm.
This will yield the following behaviour:
Going into soft limit (above 3000) - ignition will be set to 0 degrees, after 1 second, regardless of rpm reaching hard rev set limit of 4000, hard rev limit will be implemented. While hard rev limit is active, soft rev limit absolute timing will be kept at 0 degrees.

Another example:
Setting the soft rev limit to 7000, soft limit advance to -5, soft limit max time 0.0, and hard rev to 8000, will result in a hard rev limiter at -5 degrees as soon as 7000 rpm is reached, as the max time for soft limit is 0.0