730 Pump Shot

[timsiford at hushmail.com]

>AE can be a very slippery slope, and alot varies by combo., now with 
>that said, usually best to tamper with it very little if at all possible,

Believe me ... I would prefer not to mess with it ... but, my modifications 
demand it.  The MiniRam coupled with a bigger TB and higher flow ducting 
necessitates an increased pump shot.  I was able to get rid of an off-idle 
to WOT stumble by increasing the pump shot.  Thus, it can be very useful 
on cars that have seriously diverted from the original GM engine for which 
the BIN was designed.

>The AE mulitpliers are TPS, MAP, and for CTS.
>They are all used in the general fuel calulation.  Where all the fueling 
>is multiplied out for figuring the total injector on time.

Yes.  I know this.  But , again, can anyone explain the AE table (% Diff. 
TPS vs. Mult) for the 730 ECM as given in the anht_hac.pdf?  That is all 
I am trying to figure out and it seems that nobody really knows.

My experimentation has shown that increasing the values in the table increases 
the pump shot.  Although I have found this to be true I still don't understand 
the actual table format...
Why does 0% TPS have a 1.0 (or 100%) multiplier and 50% TPS have only a 
0.25 (or 25% multiplier).  A greater %TPS difference requires more pump 
shot.  So, why is the multiplier SMALLER?  How can a 0% TPS have a 100% 
Multiplier?!?

Tim

>Bruce
>
>
>> >From 90% TPS to 100% just takes a small fraction of AE compared to
>> >20-30%.
>
>> Bruce, that makes sense.  But, what I don't understand is why at 0% 
>TPS
>> has a multiplier is 100.0 and 50% Differential TPS has a multiplier 
>of
>only
>> 25.0 [insert confused look here].  That makes zero sense to me.  Opening
>> the throttle 50% needs a much bigger pump shot as compared to not 
>opening
>> the throttle at all (0%).  Yet 0% has a mult of 100 and 50% has a 
>mult of
>> 25.  Again - I think that I am missing something really simple here 
>that
>> one comment may bring to light.
>> Is Differential TPS = the delta between two throttle openings? i.e. 
>idle-
>> >WOT = 0%-100% or 100% Differential TPS?
>> Furthermore, what does the multiplier multiply?
>> Tim
>
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