rltc

[ex-ctr]

will using race logic traction control cause a problem with vems, it works by interrupting the injector signal, all i can see is that if there was a long enough period of injector cuts then the wbl will see lean and increase fueling which to me is not a problem, is there any other affects to the vems i need to worry about

[rob@vems.co.uk]

Its a damn good question and we've been discussing the possible options since you brought it up on the SXOC.
In the first case we'll need to see how it actually effects things, datalogging will show us where the problems happen.
If there is an issue with leaning then we can analyse where the problem occurs and then while the development team make the required changes, take out the lambda feedback in the areas thats causing a problem.  We do have a number of thresholds to set where the feedback is enabled: Max TPS, Min&Max RPM, Max MAP.
This way we should be able to minimise the impact.

[cliffb75]

if there was a long enough period of injector cuts then the wbl will see lean and increase fueling which to me is not a problem

You say that but depending on how much the closed loop learns you could end up in a self perpetuating loop. If you get to (or beyond) the rich misfire limit, then you will be injecting huge amounts of fuel that the engine can't burn. The lambda sensor won't necessarily detect this, as it a basically a gas analysis device - it doesn't much like raw fuel. So it may continue to think its lean and try and add more fuel!! It'll probably sort itself out again, but that potentially leaves a period where the rltc deactivates and the engine response is not that great.

You really need the rltc to output a signal saying that it is active, which of course it does as it cuts the injectors - which you can feed back into the VEMS to tell it to go open loop until the rltc has stopped doing its thing.

Just requires one of the development team to code it 

[rob@vems.co.uk]

The wideband control code factors in too much fuel through misfire and discards the readings until they are stable.

It does a load of failure checks before it decides on an action.

You can tune the speed of closed loop response.

Yeah we need a 'traction control on' line but until we know what the system is doing when it happens, and have some raw data we dont know if: a) we can handle the exceptions with config changes, or b) know what needs to be done, we cant code 'less we know what the requirements are  (although I do that almost everyday! - in the words of my mate's boss: "You start coding it, and I'll find out what it is that they want )

Rob

[ex-ctr]

what response speed does the wbl work at, are we talking milliseconds or longer, traction control cuts in for a couple of seconds at a time only so would this cause a problem, also would spark cut be better