Idle (Transition) Tuning

[bink]

What determines the transition from closed loop to WOT tune reference?

MAP and TPS%.

[Nick Williams]

Process is the same for the F-body. You just have to make sure the IAC motor is within range to give the motor the air it wants. With a big cam car the IAC uses up alot of its range or all of it just to get enough air thru for idle on a cold start. Two ways to fix this. You can drill the hole in the blade out bigger oryou can adjust the closed position set screw to open the blade more. Adjusting the screw will require a reset on the TPS to get it to read 0% at idle. The stock camaro that I have idles around 65 steps when hot. Use that as a target to determine how big of an adjustment to make. Once you have the IAC motor within range, then start trying to get the DESIAC gms/sec to match close to the MAF gms/sec.

[jfpilla]

Thanks Nick, I've added your post to the original.

[jfpilla]

And the million dollar question is

What if you dont have a maf. Can you just log DESIAC and put those values in folowing the steps above.

in this case i think you could use the dynamic air pid logged in gm/sec to replace the maf value, but i think this table is back calcualted from the ve table....


What about the lowly F-bodies :(

Dirk,
A good question. May not be worth a million, but good. I meant to give my .02 but forgot. It would seem to me that the Dynair pid would give the info you need. Isn't it's purpose for when the MAF sensor fails? I know it provides logged values when the MAF is disconnected or just 0'd. I went back and looked at those logs and the info looks consistant.
Joe

[Dirk Diggler]

Thanks again

[launchn]

jfpilla

I have a few questions about your Idle Tuning post.


1. What do you mean if the VE Tables are off by more than 20% they need to be set.

2. Input the logged MAF values into the idle airflow (raf) table, by temperature. How exactly is this accomplished?

3. Can you expand a little about this;

-Raise or lower idle airflow parked (IAC park ) values.
You want to match logged desiac and maf values.
This is done within each IAT range. You will need to watch Desiac and Maf results in Dash f10.
Raising/lowering IAP raises/lowers desiac.


These questions are just a start but should get me going.

Thanks.

[jfpilla]

jfpilla

I have a few questions about your Idle Tuning post.


1. What do you mean if the VE Tables are off by more than 20% they need to be set.

2. Input the logged MAF values into the idle airflow (raf) table, by temperature. How exactly is this accomplished?

3. Can you expand a little about this;

-Raise or lower idle airflow parked (IAC park ) values.
You want to match logged desiac and maf values.
This is done within each IAT range. You will need to watch Desiac and Maf results in Dash f10.
Raising/lowering IAP raises/lowers desiac.


These questions are just a start but should get me going.

Thanks.

To steal a recommendation by Bink:
"If you want an excellent Tuning education then do an "Advanced Search" on LS1Tech. Search the "PCM Section" for ALL posts by NoGo . You will find a Tuning library of factual info by the MAN - it's fantastic that LS1Tech has archived all of their stuff!"

What you're asking gets complicated and really, you need some background first.

What mods does your car have and what issues are you trying to resolve?

[launchn]

Right now I'm completely stock. I have a set of heads out getting worked and am looking at the G5X3. I wanted to have the tuning understood before I change these out. So far, one of the best step by steps that I have found is this post by NoGo.

http://www.ls1tuning.com/iboard/index.php?showtopic=9

[launchn]

To steal a recommendation by Bink:
"If you want an excellent Tuning education then do an "Advanced Search" on LS1Tech. Search the "PCM Section" for ALL posts by NoGo . You will find a Tuning library of factual info by the MAN - it's fantastic that LS1Tech has archived all of their stuff!"

What you're asking gets complicated and really, you need some background first.

What mods does your car have and what issues are you trying to resolve?

This has turned out to be excelent advise. I must say though my head hurts. I have basically taken all week to read through all of this and copy alot of valuable info into a document for later use.

I have been able to answer all the questions that I had. I read through your post again and can follow it all the way through.

The other HUGE breakthrough that I had was taking the time to play with some of the MAPs the EFILive can create. I can't stress how powerfull these are going to be for tuning. Right off the bat I made one for Knock Retard and one for VE (for later). For those that havent used the MAP feature, get into it!

[jfpilla]

You're inspired. I have a feeling it will turn out well. Let us know how it goes and there will likely be some questions.