safc high/low throttle point settings math

[gurov]

Originally Posted by JohnO

but you are also running lower Fuel pressure from what i remember in our previous conversation ..

You can run large injectors but only with in the scope of what the LT ft can handle +/- 30 ... plus you LTFT I believe affect your OPEN loop maps so pusle width woudl be adjusted and pulse width would not equal fuel flow from the larger injector to the smaller but you would have the AFC to take care of that at open loop .. ..


regradless .. you can do it .. there is just a limit to it ..

hmm, where is that +/- 30 coming from ?
it sure as hell feels like LTFT affects openloop maps, cause i'm running 13.2 with like -8 adjustment on the safc up from 3000 rpm.

[JohnO]

Originally Posted by gurov

hmm, where is that +/- 30 coming from ?
it sure as hell feels like LTFT affects openloop maps, cause i'm running 13.2 with like -8 adjustment on the safc up from 3000 rpm.

ECU limit ..the FT is there for condition driving and any system problems not for actually running larger injectors...

basicly at that point the ECU says enough and just runs open loop and throws a cel .. every car has limit set from the the manufactuere .. subbies are 25%+/- ... Regardless this info has been posted on here as the Spec's limit on FT I think Mike Kojima posted that .. i also think that Travis got the same info from Clark .. and i know that is what Sahra told me when i was making plans to boost because i asked tht specificly to see how much room i had to play with ....

also as far as LTFT affecting open loop .. im pretty sure it does but people have debated with me otherwise here so i won't call it a fact but my personal opinion until i can do some heavy testing or someone else can ..

now from what your are stating is seems to back our assumption on that with your injectors but still

[pio!pio!]

Originally Posted by pugnex

Now...why is there even open loop? Wouldn't it make sense for the car to run stoich. at all times??? Why stop reading from the O2 sensor?

because
1) factory o2 sensors are not sensitive enough..they can't read accurately at certain regions of AF ratios
There are wideband o2 sensors that can do what you want..but they don't last as long as factory units.

Also you don't want to run at stoich all the time because the engine would overheat. The cooling system on cars is not adequate enough so use put in some extra fuel to cool down the system

[HumboldtBlazer]

Man this turned out to be a sweet thread. I learned a lot, and everytime I read read it I pick up on something else. STICKY?

[gurov]

Originally Posted by JohnO

ECU limit ..the FT is there for condition driving and any system problems not for actually running larger injectors...

basicly at that point the ECU says enough and just runs open loop and throws a cel .. every car has limit set from the the manufactuere .. subbies are 25%+/- ... Regardless this info has been posted on here as the Spec's limit on FT I think Mike Kojima posted that .. i also think that Travis got the same info from Clark .. and i know that is what Sahra told me when i was making plans to boost because i asked tht specificly to see how much room i had to play with ....

also as far as LTFT affecting open loop .. im pretty sure it does but people have debated with me otherwise here so i won't call it a fact but my personal opinion until i can do some heavy testing or someone else can ..

now from what your are stating is seems to back our assumption on that with your injectors but still

he said/she said, ugh. could you please find the thread/article with that +/- 30 number, i'm rather interested in how far i could push the stock ecu (for kicks mostly).