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Re: 730 Pump Shot



Squash,

My changes are as follows...

The stock GM tables is as outlined in the previous e-mail.  I have changed 
my table to the following Multipliers....
Mult(%)
100
100
100
75
55
55
55
55
45
45
45
45
45
45
45
45
45



hu, 12 Oct 2000 14:19:17 -0700 (PDT), Squash <realsquash@yahoo.com> wrote:

>
>How drastic were your changes?  I was in the middle of figuring this 
>out when my truck got a
>little injury, so AE tuning had to stop.  I'd like to help figure it 
>out.
>
>Squash
>
>--- timsiford@hushmail.com wrote:
>> >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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>
>
>=====
>Trains, Trucks, and EFI at http://www.trailrunners4x4.org/users/realsquash
>
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