inject starting deg is always the same??(when to start injec

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settra
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Re: inject starting deg is always the same??(when to start i

Post by settra »

russian wrote: I hope you are going to use a DIY microcontroller from silicon and copper? :)
xaxa :P dont challenge me !! i arledy had a course, on the physics of semiconductors :P
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Fred
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Re: inject starting deg is always the same??(when to start i

Post by Fred »

There is also an Ozzy open source wideband project on this forum and on github, and Alan's open source wideband project, too. No brainer.

BTW, DonTZ125, I'm not saying timing the pulses doesn't help, that I'm a big fan of, that's the main thing: Each cylinder gets an even homogeneity, not some running on vapour and others on droplets. There are lots of ways to skin that cat. On a four cylinder you can inject in the following three ways and get a smooth pristine idle:

1) Once per cylinder, timed the same (sequential)
2) Twice per cylinder, each timed the same (semi sequential)
3) Four times per cylinder, each timed the same (batch)

ALL of these will result in a smooth idle with good efficiency. The lower down the list you go the more automatic the smoothness is. The higher up the more you MUST tune that timing for it to behave right.
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DonTZ125
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Re: inject starting deg is always the same??(when to start i

Post by DonTZ125 »

Hi, Fred.

True enough, bearing in mind the need for increased accuracy of the dead time as the number of pulses goes up. You can also run into linearity issues at very small pulse widths, typically encountered when using multiple pulses with oversized injectors needed for either high boost or high revving engines.
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Fred
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Re: inject starting deg is always the same??(when to start i

Post by Fred »

Absolutely! However with appropriate injector modeling and/or rudimentary injector modeling + small injectors, it's fine ;-) Where you run into issues is with big injectors and no or bad data and no or bad modeling (eg M$1 and M$2 have linear battery comp for this). However we're WAY off topic now, the timing is non-critical, this is a fact. The biggest change you'll get is "noticeable" (but still minor) unless your engine is ULTRA wild, then it can matter.
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n00bs, do NOT PM or email tech questions! Use the forum!
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