General Spark Cut rev limiter on 1G DSM/GVR4

[basshead]

Hi all!

My name is Kim (yes i'm a dude...) and i write code for the 1G ECU. I'm also known as KaxLon.
I have done all kinda crazy mods like 4000Hz MAF logging range, 200+Hz datalogging, REAL speed density (no MAF fooling like ecmlink or jackal/warewolf) with loggable VE map, 16000 RPM fuel and timing maps, and so much more.
I am also the same person that cracked the logging protocol for 1G ECU on TunerPro.

I just wanted to show you all that spark cut rev limiting is possible thru code even on the 1G ECU. Everyone said it cannot be done. Well it has been done now!

Enjoy!

Video:

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Cut rev limiter on a DSM GVR4 ECU - YouTube

 

[jjw205]

Interesting. What advantage is this over the factory fuel-cut rev limiter?

 

[basshead]

Thanks!

Well once the spark can be cut all kind of possibilities open up. For instance rotational idle. It's a special kind of anti-lag system that rally cars use or it can be used on the drag strip too.

Rotational idle builds boost under idle conditions and cools the engine at the same time using fuel. The usual stutter box or ALS requires high RPM and builds alot of heat.
With rotational idle the turbo acts almost like a supercharger on a supercharged car.



Here is a video demo of me trying the first version on the car:

[ame=http://www.youtube.com/watch?v=_RPVAZ7BCF8]SwD Spark Cut Rotational Idle Alpha Test - YouTube[/ame]

 

[donniekak]

Are you writing tuner pro .xdf's for this? Or only raw hex?

 

[basshead]

The code is a total re-work done in assembly language. Hex editing is a thing of the past. I still do it since it's faster to do sometimes.

And yes i use TunerPro as front end since it's so flexible. Great logger with history tables, etc.
With my modded code i get 200+Hz logging speeds. Despite what other people say about TP's logging it's awesome since i can set the timeouts, which is not possible in any othe DSM logging software. Timeouts can be as low as 1 ms on a good laptop.
The reason i know this is that i wrote the first ADX protocol that worked with the DSM ECU.


The reason it has double values is that i used a 2 ms timeout.

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The speed density code i have written is pure and does not have anything to do with the MAF signal anymore. ECMLink, Jackal & Warewolf still uses the MAF data. Just a band aid and not real SD.

 

[donniekak]

Is the fueling setup like aem, injector pulsewidth against rpm, and manifold pressure, with no ve table, with separate target afr table?

 

[basshead]

Donnie, yes it can be setup that way too. See option 5 and 6.

Here are the standard settings so far for injectors, MAP sensor, and offsets for compensation:

1 - 2 bar MAP sensor, with offset adjust.
2 - 3 bar MAP sensor, with offset adjust.
3 - 4 bar MAP sensor, with offset adjust.
4 - 5 bar MAP sensor, with offset adjust.
5 - No MAP sensor compensation, just VE map and AFR map for fuel calculations, with scaling for VE map.
6 - No MAP sensor compensation, with offset adjust, and VE map and AFR map for fuel calculations.

In option 5 & 6 the VE map will act as a injector pulse width table.
in option 1 to 4 the offset corrects for poor MAP sensor voltage. Say you want it to top out at 2 bar boost (30 psi) but it only reaches 1.9 bar coz of voltage drop at the MAP sensor, simply adjust the offset and the maps will align up to 2 bar.

Damn i hate posting in the offtopic section of the forums, but i can't do tech posts before i do 30 newbie posts...
And the posts in hangout doesn't count i guess.

BTW, Donnie i remember buying a set of 1000cc injectors from you a few years back. It was on the galantvr4.org board. My name there is swe_gvr4_1991.