Volumetric efficiency table

[swagaero]

Ludis Langens wrote:
> 
> I've pulled what I think is a volumetric efficiency table from an ECM.  Below,
> the numbers have been manipulated into a more human understandable form.  I
> have no way to tell what raw number means a VE of 1, so the raw bytes have
> been scaled such that the largest is close to 1.  The rows are labeled with
> the MAP pressure in KPa, the columns with the engine RPM.
> 
>     |  800 1200 1600 2000 2400 2800 3200 3600 4000 4400 4800 5200 5600 6000 6400
> ----+---------------------------------------------------------------------------
>  20 | .418 .429 .473 .583 .616 .622 .660 .715 .737 .737 .726 .660 .600 .545 .528
>  30 | .462 .506 .517 .627 .649 .660 .715 .759 .787 .787 .776 .710 .649 .594 .578
>  40 | .534 .578 .594 .671 .693 .704 .776 .825 .858 .858 .847 .781 .721 .666 .649
>  50 | .605 .633 .638 .715 .754 .754 .809 .858 .891 .891 .880 .814 .754 .699 .682
>  60 | .616 .649 .677 .759 .787 .803 .853 .891 .924 .924 .913 .847 .787 .732 .715
>  70 | .627 .693 .732 .798 .825 .836 .875 .935 .952 .952 .941 .875 .814 .759 .743
>  80 | .710 .754 .781 .825 .842 .869 .908 .952 .968 .968 .957 .891 .831 .776 .759
>  90 | .748 .776 .825 .842 .864 .891 .935 .963 .979 .979 .968 .902 .842 .787 .770
> 100 | .798 .814 .853 .875 .891 .913 .957 .990 .990 .990 .979 .913 .853 .798 .781
> 
> Does this look like a real VE table?  Or is some other data built into each
> table entry?  (I didn't expect so much variation caused by MAP differences.)
> 
> I do like the sweet spot from around 3 to 5 K!
> 
>                    unsigned long BinToBCD(unsigned long i) {unsigned long t;
> Ludis Langens         return i ? (t = BinToBCD(i >> 1), (t << 1) + (i & 1) +
> ludis at netcom.com                 (t + 858993459 >> 2 & 572662306) * 3) : 0;}


	Now write yourself a quickie program to graph this and you will see
what happens to the opening time for the injectors at the various RPM
and that there is no difference between a four cyl and a 8 cylinder
system. The second part is when you put a high duration cam in and start
the base line of the vacuum at a different point it is easier to modifiy
the map signal via electronics then the table.
GM modifys the table the same way and them dumps the new table back to
the EEPROM real time while it's running ect ect. To build HP just Fatten
the table sraight across and bring the A/F to 10 to 1 instant hp.

Steve  

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