Injector PW tables -> help me understand...

I've been comparing my stock tune vs. tunes I downloaded from the HPT repository and notice that the custom tunes have changes to the injector PW tables.

Apparently I don't understand what these tables are for. My interpretation was that for a given commanded fuel and rail pressure, the table would give the appropriate PW to deliver that amount of fuel. So, if you are not changing out the injectors for higher flow injectors, why would you tweak this table? I was thinking you could just adjust the base quantity vs. TPS tables to accomplish additional fueling?

Thanks

I have seen this in other tunes people have made and it seems to me that uping the injector pw tables tricks the computer to spraying fuel like you have larger injectors. A specific tune i saw uped them by 20% over the whole table. Lately i have only uped that table 10% then on the base fuel table i have taking everything past 50% throttle posistion and adding 15 to that number. I dunno if this works the same or not because the truck seems to run about the same. hope this helps a little sorry i dont have more info.

jason

I have seen this in other tunes people have made and it seems to me that uping the injector pw tables tricks the computer to spraying fuel like you have larger injectors. A specific tune i saw uped them by 20% over the whole table. Lately i have only uped that table 10% then on the base fuel table i have taking everything past 50% throttle posistion and adding 15 to that number. I dunno if this works the same or not because the truck seems to run about the same. hope this helps a little sorry i dont have more info.

jason

Thanks for the response, Jason.

Wow... 3 days and my post is still the top one on the forum... not much traffic here, is there... :(

Give us time to learn it. :) You know the off the shelf tuner just do not change much.

the pulse width table is simplly telling the computer how long to keep the injector spraying, I have played with these tables quite a bit and have not had good luck with modifying the whole table with a certain %, tried that. you have to logg some scan time and unerstand the table, and unerstand what part of that table relates to eater bottom end , midrange , top end ( rpm not power) then you can tune a really good table that has no drivaility issues , that some other peoples tune that I have tried have had.
you have to at some point start playing with your timing( injectoin timing)
to start really making some good tunes but be carefull a little change goes along ways, and not the whole table needs advancing sart oiut with a .1 degree change and see what happens you can actuuly feal a 1/10 of a degree, but tune at your own risk but this has worked well for me !

You guys can read into the post from efi live there is alot of info there that will help you guys out. It is different software but the changes made to the tables will be basically the same maybe just wrote in a little bit different format. They both probably have almost all the same tables (pids) but just displayed a little different.