High Altitude Tuning

[WeathermanShawn]

Hello:

First, I would like to introduce myself. I am a Meteorologist living in the Denver, Colorado area.

Purchased EFILive about 3 weeks ago, and now I'm hooked! Have put in about 4-6 hours a day reading all the tutorials, threads, and doing 'practice' tunes on my car. Have utilized the search function, and like everyone will undoubtedly make a few mistakes along the way. Wideband purchased and hopefully installed this week.

But, I must say it has been very educational working my way through the material, loading some 'practice' tunes, etc. Yes, not the recommended way to begin tuning, but maybe a few of us have done the same thing.

A few general questions that the tutorials along with the search function, have still left me with some questions that I am hoping someone can clarify.

1. M6 Spark Smoothing: What is its purpose? Is it a PCM related smoothing function? Do most tuners use it, or is it just another parameter that could possibly bias your tuning goals?

2. Catalytic Converter: Disable or Enable. (I have cats)

3. C6101: ETC Predicted Airflow. Is this purely an engine diagnostic function, or if I use a 'stock' value that is not correct, is there any undesirable effect.

My goal and intent is to have a more pleasurable high performance ride. This is a street driven car (95% of time), with a couple of track runs a year. Without starting a SD vs MAF debate, my main concern is to have a consistent tune that can handle the many variations of driving in a state where there are over 1000 mountain peaks above 10,000 feet.

I would sincerely appreciate any thoughts or clarifications concerning these items.

[TAQuickness]

Hello:

First, I would like to introduce myself.

I am a Meteorologist living in the Denver, Colorado area.

Purchased EFILive about 3 weeks ago, and now I'm hooked! Have put in about 4-6 hours a day reading all the tutorials, threads, and doing 'practice' tunes on my car.

Have utilized the search function, and like everyone will undoubtedly make a few mistakes along the way.

Wideband purchased and hopefully installed this week.

But, I must say it has been very educational working my way through the material, loading some 'practice' tunes, etc. Yes, not the recommended way to begin tuning, but maybe a few of us have done the same thing.

Welcome to the forum Shawn. Looks like you're off to a great start.


A few general questions that the tutorials along with the search function, have still left me with some questions that I am hoping someone can clarify.

1. M6 Spark Smoothing: What is its purpose? Is it a PCM related smoothing function? Do most tuners use it, or is it just another parameter that could possibly bias your tuning goals?

If memory serves, this is to help prevent the engine from flaring in between shifts. Unless you are into the detailed spark tuning phase, I have not found much of a reason to disable this feature. The transient data produced can be filtered out.


2. Catalytic Converter: Disable or Enable. (I have cats) Except for certain tuning processes, I'd leave them enabled.


3. C6101: ETC Predicted Airflow. Is this purely an engine diagnostic function, or if I use a 'stock' value that is not correct, is there any undesirable effect.
This is only applicable to fly-by-wire systems (Corvettes and later model vehicles - not F-Bods). This table serves as a fail safe mechanism for the ETC. If the measured air mass exceeds what the PCM is expecting, the PCM will put the car in limp mode in effort to thwart catastrophic damage.


My goal and intent is to have a more pleasurable high performance ride. This is a street driven car (95% of time), with a couple of track runs a year. Without starting a SD vs MAF debate, my main concern is to have a consistent tune that can handle the many variations of driving in a state where there are over 1000 mountain peaks above 10,000 feet.

I would sincerely appreciate any thoughts or clarifications concerning these items.

Thank you.

..WeathermanShawn..

Your goals are easily obtainable. Just remember to read, ask questions, read, ask questions, read, ask questions, take a baby step, evaluate the results, then read, and ask more questions. We're all here to help.

[WeathermanShawn]

Thanks for the welcome TAQuickness.

Appreciate the clarification on those issues.

[VortechC5]

The only real issue that you will find at this altitude (I live at 7300 feet) is that you will only be able to get to about 80-85kpa manifold pressure. With air density here you just can't get above that (without boost).

[WeathermanShawn]

VortechC5..

Noticed that immediately when I started scanning. 84Kpa manifold pressure was my max.

It will be interesting to actually start the VE mapping. Wideband goes on this week. No more guessing on air and fuel. Maybe everybody goes through that short period of time (pre-wideband) where they think they can just figure it all out through trims etc.

[TAQuickness]

I remember those days.