Tuning cranking pulse in 130-170f coolant range
#1
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Tuning cranking pulse in 130-170f coolant range
Hey guys, I've been running my Reverant MS2v3 for awhile now (8-9 months). I've gotten most everything tuned to my satisfaction except the warm-ish start after sitting heatsoaked for an hour or two that people report a lot of problems with.
Anything < 110 or so (cold), or > 180 (hot start after sitting for just a few minutes) works pretty well. Starts right up with no issues.
But anything between those ranges takes a long time to start (I can crank for 10-12 seconds, stop, then re-try for another 7-8 seconds before the engine finally "catches"). I've got my IAT placed on the cold side of my intercooler.
One thing I've noticed: When it's having trouble starting in this range, holding the gas pedal approx 40% throttle position seems to help it start right up in just a few cranks. I'm not sure if this means I need to add more fuel (cranking pulsewidth), or more air (PWM cranking duty)? I've tried playing with both, without much success/help to what I've already got.
I've attached what I think are relevant tables and my current tune, if anyone has any suggestions it'd be appreciated!
Anything < 110 or so (cold), or > 180 (hot start after sitting for just a few minutes) works pretty well. Starts right up with no issues.
But anything between those ranges takes a long time to start (I can crank for 10-12 seconds, stop, then re-try for another 7-8 seconds before the engine finally "catches"). I've got my IAT placed on the cold side of my intercooler.
One thing I've noticed: When it's having trouble starting in this range, holding the gas pedal approx 40% throttle position seems to help it start right up in just a few cranks. I'm not sure if this means I need to add more fuel (cranking pulsewidth), or more air (PWM cranking duty)? I've tried playing with both, without much success/help to what I've already got.
I've attached what I think are relevant tables and my current tune, if anyone has any suggestions it'd be appreciated!
#4
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Thanks Westfield, I'll give that a shot. I wasn't sure if 50% throttle means more fuel AND air is introduced, or just more air.
I have my wideband hooked up to a power source that cuts during cranking, if I move it to a source that keeps power during cranking will it tell anything useful since the engine won't be firing?
I have my wideband hooked up to a power source that cuts during cranking, if I move it to a source that keeps power during cranking will it tell anything useful since the engine won't be firing?
#5
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you inject based on the cranking pw% table, so if it starts better with more throttle, then you should reduce the PW at that CLT temp.
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