[Diy_efi] Re: Minimalist micro based EFI ?

Mike erazmus at iinet.net.au
Tue Mar 11 15:31:14 GMT 2003


Yes Mos, but not from the perspective of a design decision to
run an engine over a certain power come boost range...

ie. A Gen III 5.7L V8 uses a MAF sensor 5v max output, 300Kw

A RB30 N/A puts out 120 Kw and uses a different MAF sensor also
with a max 5v output.

Case 1 above at say 100Kw flow has less MAF voltage than the
case 2 with 100Kw flow as its a sensor sizing throat/voltage issue.

So clearly the sensor is chosen for the range and the a/d resolution
is chosen under some other metric, other than the difference in
vintage between the 2 samples above, is there a compelling reason
the 5.7L V8 *needs* higher resolution if emissions is not an issue,

rgds

mike



At 02:06 AM 3/12/03 +1100, you wrote:
>On Tue, 11 Mar 2003, Mike wrote:
>
>> At 01:38 AM 3/12/03 +1100, you wrote:
>> >> <cough> I dont see how boost has anything to do with the number of bits.
>>
>> So now you are saying air flow voltage is related to boost pressure
>> rather intimately ?
>
>There's no standard (that I was referring to). I was referring to MAP and
>atmo - hence 5V/1bar (yes, very generally). As another poster stated,
>there's 5V/3bar (and also 5V/2bar).
>
>It doesn't matter what you're measuring, but if your range increases, your
>resolution will decrease if you use the same number of bits, period. Your
>10 bits will not give you the same resolution with 2 bar as they will with
>1 bar.
>
>I was in no way saying that it was insufficient - merely stating that
>boost *can* affect the number of required bits - so yes, boost does have a
>lot to do with the number of bits.
>
>Air flow voltage is related to air flow (obviously), and air flow is very
>intimately related to boost pressure.
>
>Mos.
>
>-- 
>84 AE86, 90 ST185GrpA, 91 MX83Gr, Sydney, Oz.
>
>
>
>_______________________________________________
>Diy_efi mailing list
>Diy_efi at diy-efi.org
>http://www.diy-efi.org/mailman/listinfo/diy_efi
>
>

_______________________________________________
Diy_efi mailing list
Diy_efi at diy-efi.org
http://www.diy-efi.org/mailman/listinfo/diy_efi



More information about the Diy_efi mailing list