russ k idle config question
With no information it looks like your IAC table is way off. Likely a stock table with a larger throttle. Or a large hole drilled in blade. Or both.
Use your dynamic airflow numbers instead of desired airflow. Check out ChopperDoc vid on how to calibrate iac. It is not perfect but will get you close.
Use your dynamic airflow numbers instead of desired airflow. Check out ChopperDoc vid on how to calibrate iac. It is not perfect but will get you close.
Thread Starter
Staging Lane
Joined: Feb 2016
Posts: 77
Likes: 1
its a frost tune, only thing i changed is the idle airflow as it was dipping after throttle. idles and drives nice but smells rich until its up to temp thus the reason i tried the russ k. your probably right about the iac, when i first adjusted the throttle body after the cam i was around 30-35 counts warm now im at around 10. but i set that up in dec. so temperature is much different now. ill look into it, thanks for the advice.
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Idle airflow (Base Running Airflow) defines what the values on the IAC table are, essentially. I would suggest as Darth said, use dynamic values for your RAF table instead of "idle desired."
OR you can return the table to what you had before, and then fix the "dip" using spark, since that is way more effective for fixing return to idle problems than air is. For the air, you just need to get the ranges right. Spark is far more useful in correcting a hang or a undershoot. Try making your 400 and 600 RPM columns on your idle spark tables 30 or 35 degrees. That's like a built in stall saver. I go ahead and smooth them to the next column (interpolating) so the 600 column so it ends up being like 25 or something like that.
I'll try and remember to post a picture of what that looks like later, can't now I'm at work.
OR you can return the table to what you had before, and then fix the "dip" using spark, since that is way more effective for fixing return to idle problems than air is. For the air, you just need to get the ranges right. Spark is far more useful in correcting a hang or a undershoot. Try making your 400 and 600 RPM columns on your idle spark tables 30 or 35 degrees. That's like a built in stall saver. I go ahead and smooth them to the next column (interpolating) so the 600 column so it ends up being like 25 or something like that.
I'll try and remember to post a picture of what that looks like later, can't now I'm at work.
Thread Starter
Staging Lane
Joined: Feb 2016
Posts: 77
Likes: 1
Idle airflow (Base Running Airflow) defines what the values on the IAC table are, essentially. I would suggest as Darth said, use dynamic values for your RAF table instead of "idle desired."
OR you can return the table to what you had before, and then fix the "dip" using spark, since that is way more effective for fixing return to idle problems than air is. For the air, you just need to get the ranges right. Spark is far more useful in correcting a hang or a undershoot. Try making your 400 and 600 RPM columns on your idle spark tables 30 or 35 degrees. That's like a built in stall saver. I go ahead and smooth them to the next column (interpolating) so the 600 column so it ends up being like 25 or something like that.
I'll try and remember to post a picture of what that looks like later, can't now I'm at work.
OR you can return the table to what you had before, and then fix the "dip" using spark, since that is way more effective for fixing return to idle problems than air is. For the air, you just need to get the ranges right. Spark is far more useful in correcting a hang or a undershoot. Try making your 400 and 600 RPM columns on your idle spark tables 30 or 35 degrees. That's like a built in stall saver. I go ahead and smooth them to the next column (interpolating) so the 600 column so it ends up being like 25 or something like that.
I'll try and remember to post a picture of what that looks like later, can't now I'm at work.
Sometimes you need to go to your idle spark tables and run less spark so you can run more adaptive spark.
At idle, peak tq is at 33 degrees. If you run 20 base, put 12 in at -100 rpm error and interpolate to zero. Put -12 in at +100 rpm error and interpolate. If you find you need more adaptive control, drop base to 18 and run 14 at 100 rpm error. Slight increase to base air to compensate.
Helps a lot with stability. Reduce your follower decay to slow your return to idle cam help too
At idle, peak tq is at 33 degrees. If you run 20 base, put 12 in at -100 rpm error and interpolate to zero. Put -12 in at +100 rpm error and interpolate. If you find you need more adaptive control, drop base to 18 and run 14 at 100 rpm error. Slight increase to base air to compensate.
Helps a lot with stability. Reduce your follower decay to slow your return to idle cam help too
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Thread Starter
Staging Lane
Joined: Feb 2016
Posts: 77
Likes: 1
i think i need to go back to square one and start again. i think i created a problem by fixing one. my tps voltage is higher than id like eventhough it reset to 0%. do i add timing to the base=high/low octane or the idle spark advance? it does look like he lowered the underspeed from 9 to 4, which by what darth is saying is the wrong direction.
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Verdad Gallardo Typically if you've got a big cam or something you cut the idle under/over spark control so you don't end up with a constantly swinging timing that is over/under correcting drastically. if you're in park, you use the idle spark table. In gear is the high/low octane table. Make sure idle cells match for both tables.
Originally Posted by ss55539
i think i need to go back to square one and start again. i think i created a problem by fixing one. my tps voltage is higher than id like eventhough it reset to 0%. do i add timing to the base=high/low octane or the idle spark advance? it does look like he lowered the underspeed from 9 to 4, which by what darth is saying is the wrong direction.
Originally Posted by ddnspider
Typically if you've got a big cam or something you cut the idle under/over spark control so you don't end up with a constantly swinging timing that is over/under correcting drastically. if you're in park, you use the idle spark table. In gear is the high/low octane table. Make sure idle cells match for both tables.
I detorque the idle so that I can use more corrective air and spark to help contain it. Again, this is when the normal stuff stubbornly refuses to stabilize.
Edit - I also do not worry about making the main tables match the idle tables. Which table is used is controlled by speed and tps.
Speaking of, what is your tps voltage at idle?
Thread Starter
Staging Lane
Joined: Feb 2016
Posts: 77
Likes: 1
i really appreciate the info guys. and sorry for the dumb questions im more of a visual guy. so just to be clear when raising the timing as chopper said do i use the red or yellow circle? m6 car by the way.
Thread Starter
Staging Lane
Joined: Feb 2016
Posts: 77
Likes: 1
Typically people will follow ddn advice and it works most of the time. What I am suggesting you do works when the normal method does not work. You are correct that my advice is opposite of what is typically done.
I detorque the idle so that I can use more corrective air and spark to help contain it. Again, this is when the normal stuff stubbornly refuses to stabilize.
Edit - I also do not worry about making the main tables match the idle tables. Which table is used is controlled by speed and tps.
Speaking of, what is your tps voltage at idle?
I detorque the idle so that I can use more corrective air and spark to help contain it. Again, this is when the normal stuff stubbornly refuses to stabilize.
Edit - I also do not worry about making the main tables match the idle tables. Which table is used is controlled by speed and tps.
Speaking of, what is your tps voltage at idle?
Thread Starter
Staging Lane
Joined: Feb 2016
Posts: 77
Likes: 1
when i first installed the cam it was around 30-35. now without changing anything itll get down to around 10, but it was probably 50 degrees when i initially set that up now its 90+ and humid.
Last edited by ss55539; Sep 11, 2019 at 03:39 PM.
Thread Starter
Staging Lane
Joined: Feb 2016
Posts: 77
Likes: 1
Ok so I was finally able to find some time. I changed the tune back and set the throttle body back. I'm at .55 volts on the tps, idling warm at around 45 IAC counts. Added some timing like advised above and played with the underspeed car still dips. If you drive say 3 or 4 blocks it's fine 90% of the time. Low speed, back and forth, parking lots, it's really bad. Rpm will drop to around 350 then recover. I did notice it's much better if I have the rpm set at 850 instead of 800. I don't think the idle should have to be set that high though.