[Diy_efi] fast-ish 6 channel data logger

[niche at iinet.net.au]

I recall reading somewhere the factory ecu for the nissan rb30
motor has an exception in that it actually fires past TDC by
anything from 5 to 10deg for very low voltage when cranking slow...
Seems like a logical state condition which if really cold climates...

Rgds

mike



At 04:59 PM 20/04/05, you wrote:
>actually i the problem is to see if the events are really sinchronous. for example, the engine likes to kick back when cranking, and cannot be 100% sure the ECU is sparking exactly at 0 TDC. i suspect the spark timing and perhaps injection duration is somewhat erroneous when cranking due to the variable angular speed of the crankshaft. 
>
>remember, this is more or less a homemade ECU, so some validation of whhat it does is the goal of this.
>
>
>saluti
>
>gm
>
>
>> -----Original Message-----
>> From: diy_efi-bounces at diy-efi.org [mailto:diy_efi-bounces at diy-efi.org]
>> Sent: Dienstag, 19. April 2005 20:24
>> To: diy_efi at diy-efi.org
>> Subject: RE: [Diy_efi] fast-ish 6 channel data logger
>> 
>> 
>> mmmm,
>> 
>> you may not need to record so many events at the same time if they
>> are synchronous, I understand now you are looking for the 
>> instantaneous
>> change in rotational acceleration. Id grab a crank angle sensor
>> off a nissan rb30 motor - rig it up somehow and look at the 360deg
>> pulse channel - even on an analog cro it would tell a lot...
>> 
>> Mike
>> 
>> 
>> 
>> At 02:05 AM 20/04/05, you wrote:
>> >digital storage oscilloscope is a good idea, but rather 
>> expensive... considering this is a hobby
>> >
>> >just to be more precise, there seem to be issues with spark 
>> synchronization when cranking due to the engine slowing down 
>> during compression stroke and accelerating after TDC. the 
>> engine is a duke, with a rather poor starter motor. there are 
>> 2 phase sensors, one on camshaft for phase and one on crank 
>> for synch, but with only 4 teeth in the wheel.
>> >
>> >i have an analog CRO but its hard to see anything 
>> interesting. so i thought a data logger might be the answer 
>> to see what happens during several compression strokes and 
>> how spark and fueling behave and when occur compared with 
>> crank signals
>> >
>> >i have found a cheap data logger but it is limited to 240 
>> samples/second in the cheap form
>> >
>> >i guess at least 1000 samples/seconds will be necessary to 
>> see the injection/spark events
>> >
>> >
>> >regards
>> >
>> >gm
>> >
>> >> -----Original Message-----
>> >> From: diy_efi-bounces at diy-efi.org 
>> [mailto:diy_efi-bounces at diy-efi.org]
>> >> Sent: Dienstag, 19. April 2005 19:46
>> >> To: diy_efi at diy-efi.org
>> >> Subject: Re: [Diy_efi] fast-ish 6 channel data logger
>> >> 
>> >> 
>> >> Bellisimo,
>> >> 
>> >> u can get a digital storage oscilloscope to get u most
>> >> of the way there, as long as you only want to know a few
>> >> samples and dont need to keep recording under different
>> >> conditions...
>> >> 
>> >> Many DSO's on market, might need to make up a
>> >> basic interface so u dont blow the DSO front end, 
>> >> but can usually save output to file for print etc...
>> >> 
>> >> Regards from
>> >> 
>> >> 
>> >> Mike Massen
>> >> Perth, Western Australia
>> >> VL Commodore Fuse Rail that wont warp or melt !
>> >> http://niche.iinet.net.au
>> >> 
>> >> At 01:32 AM 20/04/05, you wrote:
>> >> 
>> >> >Hi all
>> >> >
>> >> >i am looking into a solution for a problem.
>> >> >
>> >> >i have a aftermarket EFI, and i would like to monitor 
>> >> exactly what happens while cranking the engine, so as to see 
>> >> exactly when spark and fueling occur in comparison with phase 
>> >> sensor pulses
>> >> >
>> >> >i have thought that perhaps a fast 6 channel data logger can 
>> >> help me there, taking 2 injectors, 2 coils and 2 phase 
>> >> sensors data fast enough to reconstruct the few seconds 
>> >> during cranking and see when different events occur.
>> >> >
>> >> >so i wondered if anyone has info on how to build this or 
>> >> something available on the market that wont cost more than 
>> >> the motorbike i am running the injection on :-)
>> >> >
>> >> >saluti
>> >> >
>> >> >gianamrco 
>> >> 
>> >> 
>> >> 
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>> >> 
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>> 
>> Regards from
>> 
>> 
>> Mike Massen
>> Perth, Western Australia
>> VL Commodore Fuse Rail that wont warp or melt !
>> http://niche.iinet.net.au
>> 
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Regards from


Mike Massen
Perth, Western Australia
VL Commodore Fuse Rail that wont warp or melt !
http://niche.iinet.net.au