Injector control

Bruce Plecan nacelp at bright.net
Sun Nov 29 00:57:59 GMT 1998


-----Original Message-----
From: Espen Hilde <mwichstr at online.no>
Subject: Re: Injector control


>I think with oemstuff,gm...If we want a greater hp aria to cower ,is to use
>2 ECM`s.Map based first ecm/stage and map on second stage.On the second
>stage maybe it is possible to lower the pressure the
>Map sensor sees.At 1.1bar the first ecm sees 1bar and the second see
>.1bar.Maybe tbi on first stage and
>tpi on second? Just to make it easy to convert an old engine?Can the two
>ecm`s share all sensors ecept
>the map sensor?.........

Not really, but only the primary ecm would need to IMHO.  The
second ecm, I'd use would have all the diagnostics flags off, and just
use the ref dist pulse.  Then use a 2 or 3 bar MAP for the secondary
ecm, and just use it to run a second set of injectors.  Maybe use two
of the 1227749's both for 2 bar MAP (OEM setup)...
  Just typing out loud
Cheers
Bruce
No, it is going to be more complicated.....the
>second stage must begin at vacum....Maybe better with two maf`s. Second maf
>comes in by trottle control, or by boost pressure if
>turbocharged.
>What do ya think?
>Espen
>>
>> >>Hi Greg,
>> >>A couple of thoughts regarding PW.
>> >>1). The smaller you make the PW (resolution) the more Processing Power
>> >>(MIPS) you need in an ECC or it forces the manufacturer to adds an
>> >>automatic sequencer so as to keep the costs under control.
>> >>2). Those of us who do performance modifications would like to add
>> >>larger injectors.  With the low cost ECC's you wrestle with a large
>> >>minimum PW which complicates idle and emmisions.
>> >>Ron
>> >I thought that was what I was trying to say!! Sure, you need more
>> >processing power and a faster processor to get smaller pw resolution.
>With
>> >a bigger injector, you need a shorter pw (higher turndown ratio) to get
>an
>> >idle that works. so you go to p&h injectors, but if you do not have fine
>> >enough pw resolution,  you still do not get decent idle tuning. Like
>> >anything else, you get to spend more money to do it right!!
>> >>> Regards, Greg
>>
>> Wouldn't just using a lower fuel pressure work?.  So as to at least have
>the
>> injector fully on?.  Do a rising rate device, rather than a
>> 1:1..   That one Bosch PWM FPR is beginning to sound better
>> all the time.
>> Bruce
>




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