What resistor do I need to pull 6 degrees of timming?
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What resistor do I need to pull 6 degrees of timming? I looked through the stickys but could not find what value resistor to install in the intake air temp circuit to pull 6 degrees of timing? I want to spray a 150 shot and want to just wire up a resistor so I can flip a switch and kill 6 degrees of timing. I have already found a post showing the wiring through a relay I just need to know witch resistor to buy.
I looked through the stickys but could not find what value resistor to install in the intake air temp circuit to pull 6 degrees of timing? I want to spray a 150 shot and want to just wire up a resistor so I can flip a switch and kill 6 degrees of timing. I have already found a post showing the wiring through a relay I just need to know witch resistor to buy.
but I do not know what ohm value it needs to be for that...
heres the table that your pcm will use...
figure out the resistance based on your IAT temperature, and you can know exactly how much timing it will pull..
easiest way is to grab a cheapy cooking digital thermostat...
find a way to heat some water with the digital thermostat in the water...
find a way to hold the tip of the IAT sensor in the water... and measure resistance when you get it to where you want it based off of this table...
use the 100kpa line as your reference for how much timing it pulls at various values
and actually... with the corvette...you can see iat on the dash...
so just buy a potentiometer, wire it in place of the IAT and twist it until you see the IAT value on the dash to do the timing.,.. then measure and buy the resistor(or multiple resistors to equal the correct value)
so just buy a potentiometer, wire it in place of the IAT and twist it until you see the IAT value on the dash to do the timing.,.. then measure and buy the resistor(or multiple resistors to equal the correct value)
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and actually... with the corvette...you can see iat on the dash...
so just buy a potentiometer, wire it in place of the IAT and twist it until you see the IAT value on the dash to do the timing.,.. then measure and buy the resistor(or multiple resistors to equal the correct value)
so just buy a potentiometer, wire it in place of the IAT and twist it until you see the IAT value on the dash to do the timing.,.. then measure and buy the resistor(or multiple resistors to equal the correct value)
maybe I'm thinking ECT... but I could swear you could see IAT on the DIC...maybe just on some of the newer ones...cant remember..its been a while since I've played with one
not without somebody changing the tune so that it can pull more timing...
in which case... have somebody set the 194* to the amount of timing you need to be pulled, then you dont have to know an exact amount for the resistor... just need anything that is above 194*
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The Tech2 scan tool that I used at the dealership I worked at can show everything. I have a friend with a preditor sport that shows timing and I have another friend that uses HP tuner Pro to retune. He wants to retune the mustang with an open loop speed density tune but as I understand it it won't referance the IAT or O2 sensors at all so I am not sure I want to go that way.
The Tech2 scan tool that I used at the dealership I worked at can show everything. I have a friend with a preditor sport that shows timing and I have another friend that uses HP tuner Pro to retune. He wants to retune the mustang with an open loop speed density tune but as I understand it it won't referance the IAT or O2 sensors at all so I am not sure I want to go that way.
he obviously should not be tuning if he thinks he should put your mustang ls1 in open loop speed density...
it wont reference the o2's at all...
the only reason to put it in open loop speed density, is if its is an all our racecar, with open headers, and never see's any street time
and then you better have a laptop and your hptuners with you every time you go out to correct the tune for the day's weather, and you better have a clue about what you are doing.
the IAT is always referenced, all the time...even if its unplugged..its still referenced,it just shows as the lowest value possible... -40* If I remember correctly
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he obviously should not be tuning if he thinks he should put your mustang ls1 in open loop speed density...
it wont reference the o2's at all...
the only reason to put it in open loop speed density, is if its is an all our racecar, with open headers, and never see's any street time
and then you better have a laptop and your hptuners with you every time you go out to correct the tune for the day's weather, and you better have a clue about what you are doing.
the IAT is always referenced, all the time...even if its unplugged..its still referenced,it just shows as the lowest value possible... -40* If I remember correctly
it wont reference the o2's at all...
the only reason to put it in open loop speed density, is if its is an all our racecar, with open headers, and never see's any street time
and then you better have a laptop and your hptuners with you every time you go out to correct the tune for the day's weather, and you better have a clue about what you are doing.
the IAT is always referenced, all the time...even if its unplugged..its still referenced,it just shows as the lowest value possible... -40* If I remember correctly
Yes it will only be used on the track but I agree with you. I want the pcm to work with the IAT and O2 sensors to compensate for DA changes...And yes I have already ran the engine without an IAT and it showed -38 degrees. In your opinion do you believe a closed loop speed denisity tune would be much better?
but I still prefer a closed loop tune when possible
the pcm will only compensate for part throttle..but if its been tuned for both part throttle and WOT, then the issue becomes daily weather...
if your car adds fuel for part throttle, it will add some at WOT, but not enough typically...and I wouldnt want to spray a 150 shot too often if the pcm wasnt adding that little bit of extra fuel for when it did need it for that day's weather...
the other direction, if its rich...it will pull fuel at part throttle, and do nothing to the fueling at WOT..so it might be a little bit rich....and you might see a little bit of a performance drop, but that is about it.
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knowing that it is a track only car... I would be ok with an open loop speed density tune, assuming you are correcting at the track every time you go.
but I still prefer a closed loop tune when possible
the pcm will only compensate for part throttle..but if its been tuned for both part throttle and WOT, then the issue becomes daily weather...
if your car adds fuel for part throttle, it will add some at WOT, but not enough typically...and I wouldnt want to spray a 150 shot too often if the pcm wasnt adding that little bit of extra fuel for when it did need it for that day's weather...
the other direction, if its rich...it will pull fuel at part throttle, and do nothing to the fueling at WOT..so it might be a little bit rich....and you might see a little bit of a performance drop, but that is about it.
but I still prefer a closed loop tune when possible
the pcm will only compensate for part throttle..but if its been tuned for both part throttle and WOT, then the issue becomes daily weather...
if your car adds fuel for part throttle, it will add some at WOT, but not enough typically...and I wouldnt want to spray a 150 shot too often if the pcm wasnt adding that little bit of extra fuel for when it did need it for that day's weather...
the other direction, if its rich...it will pull fuel at part throttle, and do nothing to the fueling at WOT..so it might be a little bit rich....and you might see a little bit of a performance drop, but that is about it.
I just said in an earlier post.......
IT ALWAYS REFERENCES THE IAT...does not matter if its open or closed loop
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That's good.....So it sounds like the resistor will pull the correct amount of timing when the car is retuned and set up for that in the tune. And if it is set up a little on the rich side the most I would give up would be a little performance with a open loop speed denisity tune correct?