Simple Transient Enrichment Brainstorming

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Fred
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Re: Simple Transient Enrichment Brainstorming

Post by Fred »

1) Yep, already fully implemented, just not shared, for various reasons. The only reason for non-TPS algos is a lack of TPS. Future refinements to current impl likely in terms of units and so forth.

2) RPM has another effect, more injections to stabilise into equilibrium for a given time frame.

3) Yep, all the tables are X vs RPM. Full pulse shape control over the entire RPM band.

4) Carb pump works on volume, same volume is induced much faster at higher RPM. If you have a 200ms enrichment then that's tiny at low RPM and HUGE at high RPM. By volume automatically compensates.
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SleepyKeys
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Re: Simple Transient Enrichment Brainstorming

Post by SleepyKeys »

The problem with just using a pure delta is that at low RPM only the fist X% of throttle movement will have an effect on airflow. IE if you are at idle and you wap the throttle to 50% there will be a huge increase in flow vs If you are lugging your engine on the highway and wap the throttle you may actually flood it out a bit. That was my reason for at least wanting to see how effective using the "fueling/PW delta" is.
A carb pump doesn't know anything about RPM,
It's sort of self-correcting. The accelerator pump dumps a flat amount of fuel based on throttle movement. The same movement at a higher RPM will automatically spread that shot out over more cylinder events.
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Re: Simple Transient Enrichment Brainstorming

Post by Fred »

Sean0 wrote:The problem with just using a pure delta is that at low RPM only the fist X% of throttle movement will have an effect on airflow. IE if you are at idle and you wap the throttle to 50% there will be a huge increase in flow vs If you are lugging your engine on the highway and wap the throttle you may actually flood it out a bit. That was my reason for at least wanting to see how effective using the "fueling/PW delta" is.
Although this is true, the amount you need for initial opening is a small proportion of what you've already got at a wider opening.
A carb pump doesn't know anything about RPM,
Fred wrote:4) Carb pump works on volume, same volume is induced much faster at higher RPM. If you have a 200ms enrichment then that's tiny at low RPM and HUGE at high RPM. By volume automatically compensates.
Sean0 wrote:It's sort of self-correcting. The accelerator pump dumps a flat amount of fuel based on throttle movement. The same movement at a higher RPM will automatically spread that shot out over more cylinder events.
I swear there's a fucking echo in here! If no LT1 log + vid + rip that all match in the next 7 days, I'm turning off your postability so you can focus better :-p
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Re: Simple Transient Enrichment Brainstorming

Post by ToxicGumbo »

Sean, if you can get a log together, do you mind posting it? This is one I'd love to play back in realtime.


-Jeff
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SleepyKeys
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Re: Simple Transient Enrichment Brainstorming

Post by SleepyKeys »

Hi Jeff,

Sure, but which engine ? R1 is available now, LT1 soonish.

-Sean
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Re: Simple Transient Enrichment Brainstorming

Post by ToxicGumbo »

/me is a closet LT1 fan. This will be like watching an EKG strapped to a celebrity pr0n star.



-Jeff
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