Need way too much idle timing
Need way too much idle timing I have a 5.3 with a tsp 220r cam and ported 706 heads. Have been chasing this thing running right since i purchased it a few weeks ago. we had been running 22 degrees idle timing, and once everything was dialed in closer, we were ready to see where it liked timing the best. I was able to give it 60 degrees initial, and it runs so much smoother at idle. KPA went from 50 to 39, was able to shut plates further, and exhaust smoothed out. So, my question to all is, why would it be happy with so much idle timing? What can i look at to figure out if something else is wrong? Thank you for any input!!
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Joined: May 2008
Posts: 644
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From: Carnation, WA
That almost seems like there is some basic error between the hardware and the software. Running a 24x tune with a 58x reluctor, or something. I think the *tune* may be set to 60 degrees, but I can’t believe the engine is actually at 60 degrees when the spark fires. Maybe there is some *other* table pulling 45 degrees.
I’m not enough of an expert to tell you that I think it’s a, b, or c, but I can’t believe the engine is really at 60 degrees… did you start with a stock factory tune?
What ECU? Can you post the .hpt file?
I’m not enough of an expert to tell you that I think it’s a, b, or c, but I can’t believe the engine is really at 60 degrees… did you start with a stock factory tune?
What ECU? Can you post the .hpt file?
Last edited by grubinski; Aug 10, 2022 at 07:24 PM.
In trying to decide if it is off across the whole board, i bumped timing up about 10 degrees in higher loads to see if it took it or not. Then drove at a low level, and could pick up the ping. So It seems to only be a weird number at idle.
yes, I am aware. I only bumped it to about 36 under throttle to see if it was close to accurate. My current WOT advance is 26 degrees. But engine still runs a thousand times better at idle with 60 degrees.
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Verdad Gallardo Low idle manifold pressure and a smooth exhaust tone aren't indicative of 'needing' all that spark. It just says you've sucked up all of your torque reserve and spark is well past MBT so the exhaust is lethargic and therefore quiet leaving the chamber. A 'happy' spark value is one that provides idle stability and load rejection, among other things. And it isn't going to be above 30 under really any circumstances in that application.
