Hi all,
So with the type of racing i do, a hard ignition and/or fuel cut has the potential to cause a very nasty accident (car written off, injuries, etc).
I'm talking about the AFR, fuel pressure, oil pressure, etc safeties btw.
Could some way be devised to enable a soft cut?
Harsh ignition retard into a progressive fuel/ignition cut. Or maybe opening up the wastegate... or something like that.
It wouldn't have as high a chance of saving the engine from damage as an immediate full cut, but it might help some.
Thanks
Soft engine safety cuts?
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Soft engine safety cuts?
Toyota Celica GT4/Alltrac with 5S-GTE stroker (2.2L I4 turbo, high CR) on E85 w/FlexFuel.
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Re: Soft engine safety cuts?
You could use the CEL feature or the programmable outputs to bring on buzzers or lights.
Andy
Andy
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Re: Soft engine safety cuts?
Curious as to the type of racing and situation where the cut will cause an accident. I have an engine that provides significant engine braking; the transition from wot to full cut is harsh, but not enough to drag tires and spin the car.
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Re: Soft engine safety cuts?
For anything other than drag racing, chopping the engine hard has the possibility of someone piling into you from behind. The original tip-over sensor systems on bikes caused quite a few mid-corner collisions, when a minor tail-flick shook the sensor and cut the engine.
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Re: Soft engine safety cuts?
I also think this would be good option for all the safety cuts. Especially for overboost protection. Besides mentioned safety factors hard cut can be really annoying and possible harmful for mechanical parts. At least on some high power bike engines that I have tuned the overboost cut is quite violent phenomenon.
Of course in ideal world you shouldn't hit these safety cuts often if ever. But in reality they can be useful help when doing initial tuning for new setup. Like when tuning boost control parameters.
Of course in ideal world you shouldn't hit these safety cuts often if ever. But in reality they can be useful help when doing initial tuning for new setup. Like when tuning boost control parameters.
Arttu
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Re: Soft engine safety cuts?
One possible idea would be to implement a ramped rev limiter that forces the RPMs down over a longer period of time.
e.g. if you hit AFR safety at 5700RPM, start the limiter at 5700RPM and bring it down to 1000RPM over (say) one second.
James
e.g. if you hit AFR safety at 5700RPM, start the limiter at 5700RPM and bring it down to 1000RPM over (say) one second.
James
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Re: Soft engine safety cuts?
It sounds like that would do the job James.
Maybe add a global soft safety cut configuration, then have each of the items (afr, fuel press, oil press, etc), have an option to use that cut.
Maybe add a global soft safety cut configuration, then have each of the items (afr, fuel press, oil press, etc), have an option to use that cut.
Toyota Celica GT4/Alltrac with 5S-GTE stroker (2.2L I4 turbo, high CR) on E85 w/FlexFuel.
MS3 + MS3X + KnockBoard + RTC + BT + DIY CAN-IO-Board + DIY CAN Digital Dash.
MS3 + MS3X + KnockBoard + RTC + BT + DIY CAN-IO-Board + DIY CAN Digital Dash.