Idle SA question
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Idle SA question
It was recommended to me that my Idle SA cells be 10* more than my base timing to reduce the tendency for idle surging. This from a reputable source.
Aside from the fact of not having a IAC connected till everything is squared away and I pick up an MS2 processor.
Here is my dilemma, You may recall my Spark dropout under load thread, where incorrect rotor phasing and faulty ICM in concert with a leaking EGR were causing the issue.
Here is what was done to correct it. Rotor phasing incorrect at 10* base timing, Pulled dizzy up and retarded it by one tooth, which in turn brought my base timing to 0*. Put the corrected value into the Megasquirt, so the Megasquirt compensated, and essentially made the base timing 10* while the bypass wire is connected. Bypass wire disconnected, base timing steady at 0*. BAM, problem solved.
Onto the question.
Taking into account the previous paragraph, and the tip to set Idle SA cells to 10* more than base timing for a smooth idle on my motor.
The question is, am I setting the Idle SA cells to 10* or 20*? Which value is the "actual" base timing, the 0* base, or the compensated 10* base in the MS?
MS1 V3 running extra code.
I don't see where a log or tune would help, but if you need them just let me know and I'll post them up.
Thanks
Aside from the fact of not having a IAC connected till everything is squared away and I pick up an MS2 processor.
Here is my dilemma, You may recall my Spark dropout under load thread, where incorrect rotor phasing and faulty ICM in concert with a leaking EGR were causing the issue.
Here is what was done to correct it. Rotor phasing incorrect at 10* base timing, Pulled dizzy up and retarded it by one tooth, which in turn brought my base timing to 0*. Put the corrected value into the Megasquirt, so the Megasquirt compensated, and essentially made the base timing 10* while the bypass wire is connected. Bypass wire disconnected, base timing steady at 0*. BAM, problem solved.
Onto the question.
Taking into account the previous paragraph, and the tip to set Idle SA cells to 10* more than base timing for a smooth idle on my motor.
The question is, am I setting the Idle SA cells to 10* or 20*? Which value is the "actual" base timing, the 0* base, or the compensated 10* base in the MS?
MS1 V3 running extra code.
I don't see where a log or tune would help, but if you need them just let me know and I'll post them up.
Thanks
Megasquirt 2 V3.0 Running Msextra 3.4.2. in a 1989 Camaro RS .48AR/60mm Turbo 3.4L/700R4
Boost control, Fan control, Stepper IAC, Launch/Antilag, Working on the GMDIS, and Methanol injection
Re: Idle SA question
Hmm, guess there is a first time for everything.
I'll just assume base timing is 10* as it normally would be on my motor....
I'll just assume base timing is 10* as it normally would be on my motor....
Megasquirt 2 V3.0 Running Msextra 3.4.2. in a 1989 Camaro RS .48AR/60mm Turbo 3.4L/700R4
Boost control, Fan control, Stepper IAC, Launch/Antilag, Working on the GMDIS, and Methanol injection
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Re: Idle SA question
All I need to know is which one of you actually wrote the post????
Ken
Ken
1979 Corvette - 383 CID SBC w/ Holley Pro-Jection 900 CFM TBI, 4-85 lb lo-z injectors & Walbro 255 pump
MS2 v3 w/extra 3.4.2 Release
36-1, Delphi LS2/7 coils in wasted spark, driven by v2.0 logic board from JBPerformance
Spartan Lambda Sensor from 14point7
TinyIOX from JBPerformance
MS2 v3 w/extra 3.4.2 Release
36-1, Delphi LS2/7 coils in wasted spark, driven by v2.0 logic board from JBPerformance
Spartan Lambda Sensor from 14point7
TinyIOX from JBPerformance
Re: Idle SA question
The raccoon of course, I'm too busy working on the car lmao!kjones6039 wrote:All I need to know is which one of you actually wrote the post????
Ken
Megasquirt 2 V3.0 Running Msextra 3.4.2. in a 1989 Camaro RS .48AR/60mm Turbo 3.4L/700R4
Boost control, Fan control, Stepper IAC, Launch/Antilag, Working on the GMDIS, and Methanol injection
Re: Idle SA question
Would the difference between rising edge and falling edge be 10*? Could that be the reason, perhaps its set wrong?
Megasquirt 2 V3.0 Running Msextra 3.4.2. in a 1989 Camaro RS .48AR/60mm Turbo 3.4L/700R4
Boost control, Fan control, Stepper IAC, Launch/Antilag, Working on the GMDIS, and Methanol injection
Re: Idle SA question
WillExoIX wrote:Would the difference between rising edge and falling edge be 10*? Could that be the reason, perhaps its set wrong?
Nobody has any input?
Megasquirt 2 V3.0 Running Msextra 3.4.2. in a 1989 Camaro RS .48AR/60mm Turbo 3.4L/700R4
Boost control, Fan control, Stepper IAC, Launch/Antilag, Working on the GMDIS, and Methanol injection
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- Super MS/Extra'er
- Posts: 17507
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Re: Idle SA question
The best way to determine the difference between the edges is with a timing light.
Matt Cramer -1966 Dodge Dart slant six running on MS3X
Re: Idle SA question
So switch it from one to the other and verify timing values with the light?Matt Cramer wrote:The best way to determine the difference between the edges is with a timing light.
Could that possibly be the reason it idles so rough? Or is that from adding a restriction to the exhaust (turbo). Idle was smooth as butter before the turbo was added.
Megasquirt 2 V3.0 Running Msextra 3.4.2. in a 1989 Camaro RS .48AR/60mm Turbo 3.4L/700R4
Boost control, Fan control, Stepper IAC, Launch/Antilag, Working on the GMDIS, and Methanol injection
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- Super MS/Extra'er
- Posts: 17507
- Joined: Thu Apr 16, 2009 8:08 pm
Re: Idle SA question
Just verify what you've got now.WillExoIX wrote: So switch it from one to the other and verify timing values with the light?
Could be this setting or it could be some of the mods when you added a turbo.Could that possibly be the reason it idles so rough? Or is that from adding a restriction to the exhaust (turbo). Idle was smooth as butter before the turbo was added.
Matt Cramer -1966 Dodge Dart slant six running on MS3X
Re: Idle SA question
Well right now with the bypass unplugged its 0* base timing. Standard base timing on this motor is 10*, but there was a rotor phasing issue before the turbo went on that was partially solved by bumping the distributor back one tooth. That caused base timing to go from 10* to 0*, but was compensated by setting the MS to 10* timing for the base value, or setting the MS to 0*, I can't quite remember which. The MS compensates for the changed base timing, and all was back to normal, put it that way.Matt Cramer wrote:Just verify what you've got now.WillExoIX wrote: So switch it from one to the other and verify timing values with the light?
Could be this setting or it could be some of the mods when you added a turbo.Could that possibly be the reason it idles so rough? Or is that from adding a restriction to the exhaust (turbo). Idle was smooth as butter before the turbo was added.
Tomorrow I will switch the setting and see what happens, Because if possible I would like to be able to put everything back the way it was beforehand, instead of band-aiding what ever the underlying issue was. It was a completely brand new distributor if it matters, and installed properly.
Megasquirt 2 V3.0 Running Msextra 3.4.2. in a 1989 Camaro RS .48AR/60mm Turbo 3.4L/700R4
Boost control, Fan control, Stepper IAC, Launch/Antilag, Working on the GMDIS, and Methanol injection
Re: Idle SA question
Didn't get a chance to check this as I was getting a log for my other issue. I will check it soon.
Megasquirt 2 V3.0 Running Msextra 3.4.2. in a 1989 Camaro RS .48AR/60mm Turbo 3.4L/700R4
Boost control, Fan control, Stepper IAC, Launch/Antilag, Working on the GMDIS, and Methanol injection
Re: Idle SA question
Quick question. Do you want me to check this with the bypass unplugged? As in base timing?Matt Cramer wrote:Just verify what you've got now.WillExoIX wrote: So switch it from one to the other and verify timing values with the light?
Could be this setting or it could be some of the mods when you added a turbo.Could that possibly be the reason it idles so rough? Or is that from adding a restriction to the exhaust (turbo). Idle was smooth as butter before the turbo was added.
Megasquirt 2 V3.0 Running Msextra 3.4.2. in a 1989 Camaro RS .48AR/60mm Turbo 3.4L/700R4
Boost control, Fan control, Stepper IAC, Launch/Antilag, Working on the GMDIS, and Methanol injection
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- Super MS/Extra'er
- Posts: 17507
- Joined: Thu Apr 16, 2009 8:08 pm
Re: Idle SA question
Check with the bypass connected.
Matt Cramer -1966 Dodge Dart slant six running on MS3X
Re: Idle SA question
Timing matches what is on screen in tuner studio. It does jump about 1* one way or the other at idle. Rock steady with the bypass unplugged.Matt Cramer wrote:Check with the bypass connected.
Trim angle was at 1*, I set that to 0.
EDIT-I see now that this was before I figured out that I had a dead cylinder from a rocker being to tight. I have since fixed that and it runs smooth again. Though I think I can finally put the distributor back where it was, because I discovered improper dwell settings for GM HEI.
Megasquirt 2 V3.0 Running Msextra 3.4.2. in a 1989 Camaro RS .48AR/60mm Turbo 3.4L/700R4
Boost control, Fan control, Stepper IAC, Launch/Antilag, Working on the GMDIS, and Methanol injection