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how is load calculated
Posted: Wed Oct 24, 2007 1:27 am
by crans
Just working some thing out so i have a full understanding of everything needed for tuning.
How is load calculated. is it purly based on the afm voltage scaled to something?
Posted: Wed Oct 24, 2007 10:42 am
by Matt
The ECU uses a forumla to work out TP (Theoretical Pulsewidth) which is used to index the fuel/timing maps
The formula is based from the AFM voltage after it gets recalibrated from the VQ map curve and then gets adjusted based on temperatiure and minor adjustment from other factors. There are some patent sheets which have the forumla on there if you want me to chase it down... its on my laptop somewhere...
NIStune pulls the value from the ECU divides by 256 (16 bit -> 8 bit) value for maptracing purposes
Posted: Wed Oct 24, 2007 10:56 am
by crans
Yeah that would be really good thanks
Posted: Thu Oct 25, 2007 2:30 am
by Matt
heres the patent
http://www.freepatentsonline.com/4787358.html
and a thread discussing TP
http://ecu2.forumwise.com/ecu2-thread725.html
I've tried attaching but this forum keeps timing out so I'll have to email the docs
Posted: Sat Nov 17, 2007 9:07 pm
by JCD
Some very nice ones here:
http://www.uspto.gov/patft/index.html ('snot very user-friendly...)
Use this search engine:
http://patft.uspto.gov/netahtml/PTO/srchnum.htm
Input these pat nrs:
4509331
4787358
7127344
once you see the text, hit the red "Images" button.
Happy reading
Posted: Sat Nov 24, 2007 7:12 am
by LMQT
Big big big thanks for this link to the patent
At least I've got all of the explication clearly detailed to understand how TP is calculated
