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Lean Throttle Transients

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Old Sep 12, 2006 | 10:41 AM
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Default Lean Throttle Transients

I'm seeing a lean condition on transients which is certainly agrivating my cam bucking. It happens on both transients from coast to part throttle, as well as part throttle to coast. Ive already tried scaling some tables in transient fueling, but im not really sure what im doing in there, and it usually results in the car driving like a bag of ***. Anyone want to shed some light on transient fueling?
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Old Sep 12, 2006 | 11:38 AM
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You may want to scale up the min fuel milligrams in the transient fuel section. I'd go by %'s as a little goes a long way.
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Old Sep 12, 2006 | 11:45 AM
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Okay, but which table. The only one directly labeled as having naything to do with "fuel miligrams" is "Min Fuel Miligrams" in teh "qualifications" section. I dont think thats what you had in mind.
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Old Sep 12, 2006 | 11:52 AM
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Originally Posted by GuitsBoy
Okay, but which table. The only one directly labeled as having naything to do with "fuel miligrams" is "Min Fuel Miligrams" in teh "qualifications" section. I dont think thats what you had in mind.
Yes, in the qualifications section in the upper left. This controls the min amout of fuel to add during transients. If this number is too low, you'll have lean transients.

Frankly speaking, if your air and fuel tables are dialed in you shouldn't have to mess with transient tuning, but then again, I'm not familiar with your specific mods.
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Old Sep 12, 2006 | 11:56 AM
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The air and fuel tables are as dialed in as they can, the problem is that the I can only go by the averages in the histogram. If the transient is lean, the persistant polling points will be rich, and will average out to 14.7. My guess is that the fuel injectors may be off a little, particularly the offset table.
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Old Sep 13, 2006 | 10:54 AM
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Get a wideband. Look for holes in ur VE table. I had one it took a while to find it. Also make sure ur timeing is not jumping around. I also lower the high gain in the adptive idle section for the P part.
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Old Sep 13, 2006 | 11:03 AM
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Originally Posted by YellowToy/A
Get a wideband. Look for holes in ur VE table. I had one it took a while to find it. Also make sure ur timeing is not jumping around. I also lower the high gain in the adptive idle section for the P part.
Yes, I have a wideband. No, I dont have any holes in my VE. No my timing is not jumping around erratically, except for at idle due to the cam. Ive been through all the basics years ago...
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Old Sep 13, 2006 | 02:52 PM
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In the throttle cracker thread the discussion led me
to stumble across a couple of "filter coefficients" in
the Dynamic Airflow section, which I think may be
responsible for large airflow reading lags. Check it
out. Not that I have anything more than suspicion
to go on, but maybe you want to play there.
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