heads/cam idle
I've been reading as much as I can, but I haven't read anything specific about how to adjust the tables.
Throttle cracker, decay, IAC effective area, etc.
Do I increase or decrease these values? What effect does increasing or decreasing do?
The IAC effective area "steps" doesn't make sense to me at all.
Throttle cracker affects how fast rpms drop when I put in the clutch. So will this get rid of the "cruise control" effect from raising RAF numbers? If so, what numbers do I mess with, and do I increase or decrease them to make the rpms drop?
Throttle cracker, decay, IAC effective area, etc.
Do I increase or decrease these values? What effect does increasing or decreasing do?
The IAC effective area "steps" doesn't make sense to me at all.
Throttle cracker affects how fast rpms drop when I put in the clutch. So will this get rid of the "cruise control" effect from raising RAF numbers? If so, what numbers do I mess with, and do I increase or decrease them to make the rpms drop?
Here's an update to anyone going through the same thing. We'll call it my idle tuning log.
I changed the cranking VE table to 90% of stock values and dropped the primary VE to 75% 400 rpm and 80% 800 rpm and 95% 1200 rpm.
Then, I did the TB set screw thingy. (to lower my IAC counts) Turned it clockwise till my throttle position was 1%. Pulled the IAC plug (the bottom one on throttle body), turned the key to on position for 30 sec, then off. Returned plug.
That's all for tonight. Gonna drive tomorrow and see how it does.
I changed the cranking VE table to 90% of stock values and dropped the primary VE to 75% 400 rpm and 80% 800 rpm and 95% 1200 rpm.
Then, I did the TB set screw thingy. (to lower my IAC counts) Turned it clockwise till my throttle position was 1%. Pulled the IAC plug (the bottom one on throttle body), turned the key to on position for 30 sec, then off. Returned plug.
That's all for tonight. Gonna drive tomorrow and see how it does.
Originally Posted by RedHardSupra
click on my sig, read the 'idle tuning writeup' that will take you through all the necessary steps to get your idle prim and proper.
But, after tuning my RAF, the IAC counts are higher, and the rpms run high while cruising. The writeup didn't cover these subjects.
IAC reduction is coming, that has to do wtih 'effective area' table.
'cruise control effect' is RAF and making sure your gas pedal goes 0-100%, get that done, and that propblem should disappear.
'cruise control effect' is RAF and making sure your gas pedal goes 0-100%, get that done, and that propblem should disappear.
Originally Posted by RedHardSupra
IAC reduction is coming, that has to do wtih 'effective area' table.
'cruise control effect' is RAF and making sure your gas pedal goes 0-100%, get that done, and that propblem should disappear.
'cruise control effect' is RAF and making sure your gas pedal goes 0-100%, get that done, and that propblem should disappear.
My gas pedal does go 0-100% as well.
You may have a little too much correction on the Throttle Cracker table. You can trim some of the areas that exceed 1 g/sec and see if that helps.
__________________
2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
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Originally Posted by RedHardSupra
it caused it? then you gotta be doing something wrong, i've seen it do wonders for all kinds of 'off throttle' situations
Well, it started sticking more the more I increased my RAF. I used your excel spreadsheet to change it twice from 2 logs I did.
I dunno, I think I read somewhere that increasing RAF can cause a cruise control effect.
Also, a lot of people who turn the screw on the TB to open it some get a cruise control effect as well, for others it "fixed" the cruise control effect.
These engines are wierd. I guess they all react differently. You just have to keep messing with stuff till it all works out. That's probably the reason why there are no "absolutes" for idle tuning. It would be easier if everyone could just set tables at X values and make it work.
Originally Posted by RedHardSupra
send me your logs to the email in the spreadsheet, i'll take a look at it.
First, I'm going to get my IAC counts in order doing the TB blade screw thing. Then I'm going to log and mess with my RAF some more using your spreadsheet.
Maybe that'll fix my problems.
If not, I'm thinking about the cracker adding too much airflow at mph. Maybe that could be causing the rpms hanging up while decellerating. I dunno. We'll see when I get there.
Ok, I went 3% throttle on my TB screw, reset to 0% and logged. Now my IAC position and desired position is 40-45 at idle warmed up (coolant 200 degrees).
I did a short log around the block and noticed that when my idle was hanging at 1200 rpm with the clutch in at 30mph, my "Idle cracker airflow" was over 1.0 g/sec. Is that normal? Or is that why my rpms won't drop till I come to a stop sometimes?
I'm probably going to wait to mess with that till I do another RAF log/change though.
I did a short log around the block and noticed that when my idle was hanging at 1200 rpm with the clutch in at 30mph, my "Idle cracker airflow" was over 1.0 g/sec. Is that normal? Or is that why my rpms won't drop till I come to a stop sometimes?
I'm probably going to wait to mess with that till I do another RAF log/change though.
