FreeEMS Specific Decoder Series

For discussing and developing different RPM/Position decoders using our superior modular architecture! One thread per pattern, please.
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Fred
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FreeEMS Specific Decoder Series

Post by Fred »

For each decoder style, there is an optimum arrangement. This optimised arrangement is what the FreeEMS specific decoder series is all about. Making the most out of a system. Each system has physical limitations and pros/cons. And each one, in OEM form, is sub-optimal, and leaves something to be desired. On with the details!
  • Mazda/Mitsu housing, optimised custom pattern inspired by Nissan RB disks!
  • Nissan RB/SR/KA etc style, optimised!
  • Honda crank + cam optimised sync wheels!
A post per type, with a thread per type on the details. This is merely an index.
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Re: FreeEMS Specific Decoder Series

Post by Fred »

The original idea was to use the Mazda/Mitsu housings and do something better with them. That turns out to be moderately complex. The limitation are optical in nature and examined in detail in this thread and the related material (on github):

viewtopic.php?f=56&t=1204
DIYEFI.org - where Open Source means Open Source, and Free means Freedom
FreeEMS.org - the open source engine management system
FreeEMS dev diary and its comments thread and my turbo truck!
n00bs, do NOT PM or email tech questions! Use the forum!
The ever growing list of FreeEMS success stories!
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Fred
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Re: FreeEMS Specific Decoder Series

Post by Fred »

The inspiration for the above was indeed the Nissan RB series setup. A stock RB engine syncs 12 times per engine cycle, or twice per cylinder. This is excellent and these engines start near immediately with all other variables nailed down. But we can do better, if we can find an accurate cutting company...

<link to come>
DIYEFI.org - where Open Source means Open Source, and Free means Freedom
FreeEMS.org - the open source engine management system
FreeEMS dev diary and its comments thread and my turbo truck!
n00bs, do NOT PM or email tech questions! Use the forum!
The ever growing list of FreeEMS success stories!
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Fred
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Posts: 15431
Joined: Tue Jan 15, 2008 2:31 pm
Location: Home sweet home!
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Re: FreeEMS Specific Decoder Series

Post by Fred »

Honda do a moderately rapid syncing system on many of their engines. CBR600RR which FreeEMS supports uses this, as does the J series V6 engine. But more is betterer. J series syncs twice per engine cycle. CBR600RR syncs 3 times per engine cycle. We can do 6 syncs per cycle with a stock 12 tooth crank wheel. More crank teeth would produce more sync points, however at some point you couldn't reliably sync due to slop in cam drives relative to the crank master signal.

<link to come>
DIYEFI.org - where Open Source means Open Source, and Free means Freedom
FreeEMS.org - the open source engine management system
FreeEMS dev diary and its comments thread and my turbo truck!
n00bs, do NOT PM or email tech questions! Use the forum!
The ever growing list of FreeEMS success stories!
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