What is Tuning? By Definition

[AJxtcman]

What is tuning a PCM?

In my opinion it is recalibrating a .bin file or a calibration file.

This could be a simple as segment swapping or total control over all the paramaters.

Not 1 single aftermarket tuning software company allows you to have control over all the parameters.

Example of Basis Tuning

• different injector size
• Aftermarket MAF
• Cam swaps
• gear ratio changes
• DTC delete
• Adjusting Fuel trims to 0
• Adjusting timing to a preset limit
• Adjusting Shift points
• Adjusting TCC engagement

Examples of more Advanced Tuning

• Adjusting the AFR and fuel Trims for max performance
• Adjusting Timing for max performance
• Adjusting shift points for max performance
• Adjusting Trans Line Pressure
• Adjusting the EGR parameters
• Adjusting Knock Retard and Sensitivity

I know you can do a ton more, but lets see what you think.

[AJxtcman]

This is HP tuners list of GM Parameters

GM Parameters

[AJxtcman]

LS1-Edit User Guide

[N0DIH]

For a great many years now, Tuning, either via a speed shop or a tuner, or racer, would change the way his/her vehicle would operate, differently from what the manufacturer designed. Either to improve on the conservative approach that say GM, etc set the car/truck up originally.

For Example:
My 1980 Turbo T/A
I added a shift kit (comp mode, B&M) to improve the THM350.
I changed the ignition timing from 24 degrees MAX timing to something more suitable
I added HD Rancho GTIII Sway Bars
I remove the turbo wastegate cruise mode bypass to speedup boost
I remove the coolant under the turbo plenum
I did some Q-Jet mods
I ran 14.21@97.3 mph.... Up from an advertised 16.0-17.0 by the major mags.... (probably was close)
And so on.... I tuned it. I read up in a LOT of magazines things that would help and did them. I had Midwest 4WD nearby to buy my goodies from (Home of Bigfoot...). Ask MANY of 5.0L Mustangs in the mid to late 80's, they HATED me! 0-40 we were tied, 40-100 they saw taillights.... I was a dead match for a 86 Vette 55-135 mph.... It wasn't bad for a 4030 lb car with 3.08's....

In all honesty it doesn't matter HOW you change it, either hard parts, software, combo of the 2, changing it to something that better matches the car/truck's needs or the drivers needs, is tuning. At least IMNASHO... (In My Not Always So Humble Opinion)

If you knew the hot rod industry, for some, especially the big names in it, as as crooked as the Illinois Governor's charges...... The catch is, they are often as slippery.... I know some, it is a MESSED UP industry when they get into big business....

[submariner409]

"In tune" or the verb "tune" implies that something is restored to its original state or frequency.

"Tune", as now applied to automotive engine systems and sometimes suspension, is a bastardized verb meaning "to alter original operating specification(s) in order to gain (maybe......) enhanced performance".

[N0DIH]

Or to correct for changes in the engine. Example: Cam change, adding base timing to the calibration.

Calibration is probably the best term to use. If something is calibrated, it is set to operate at a certain parameter. So changing the calibration changes the parameters...

So for a cam swap, the cyl pressure in the lower rpm region is lower and must be restored (compression or timing), to restore the throttle response and performance.

[AJxtcman]

In my opinion TunerCat has the best software and support. I would say EFILive is #2

If you want something added that you heard about TC will add it with no problems. TC will build a custom one on one VDF for you. With TC you could have 100% control.

[AJxtcman]

Originally Posted by AJxtcman

In my opinion TunerCat has the best software and support. I would say EFILive is #2

If you want something added that you heard about TC will add it with no problems. TC will build a custom one on one VDF for you. With TC you could have 100% control.

I got pulled away from this post.

What do you think is in a Hand held tuner like Hypertech or a Superchips?

[97EldoCoupe]

AJ I'm no expert like you are in this field but I would say all those tuners consist of is something that communicates with the vehicles PCM and changes some values in the bin file in the PCM to that of which the user chooses, user input being from a keypad and a GUI to display info to the user.

[Raze]

AJ I have a new product for you to look at since it's been used on a 2003 OEM PCM N*, auto trans that was swapped into a replica 1948 Tucker: Power Perfect SMT6 or the NEW SMT8. You can contact Bob Ida of Ida Automotive since he tuned the twin turbo'd N* w/an SMT6 on an OEM PCM/wiring harness/sensors. It's a piggyback but for the price it seems fair, $470 for an SMT8, cheaper for the 6, and for $70-100 they'll give you a wiring diagram if you need it (I wouldn't but for people who don't know what someting like a MAF sensor is it'd be helpful) and they have a tuning shop in NJ and have tuned very a many Ford GTs, and other 'big dollar' cars. I found the info very interesting...

[AJxtcman]

Bump because i am tiered of seeing all the people whining about head gaskets.

I have something to post also

[AJxtcman]

This is a link to HPTuners Help Reference guide
VCM Suite Online Help

This is the GM Parameters that you can change.
Parameters - GM

This is the How To section
Tuning How To Section

In the Tuning How to you will find Basic and Advanced

Basics

Rear Gear/Tire Ratio

Shift Points

Timing Advance

Air/Fuel Ratio

Injectors

RPM Limiters

[AJxtcman]

Just so we all understand!

I can change the following on a Northstar PCM as described by HPTuners Definitions

1. Gear Ratio
2. Shift Points
3. Air/Fuel Ratio
4. RPM Limiters
5. Timing Advance

The Timing Advance I need to spend more time on. I think I need to look for a 3rd table. I never thought about a 3rd table until another member posted some info on Octane Level Displayed
Take a look at this
GM > Engine > Spark Control > Spark Advance

[AJxtcman]

Originally Posted by AJxtcman

Just so we all understand!

I can change the following on a Northstar PCM as described by HPTuners Definitions

1. Gear Ratio
2. Shift Points
3. Air/Fuel Ratio
4. RPM Limiters
5. Timing Advance

The Timing Advance I need to spend more time on. I think I need to look for a 3rd table. I never thought about a 3rd table until another member posted some info on Octane Level Displayed
Take a look at this
GM > Engine > Spark Control > Spark Advance

What if I skewed the MAF reading? Would it do all the above?

I have not done that! REPEAT I have not done that!!

I just want you to think about Tuning and what 1 adjustment could do!!!!!!!!!!!!!!!!!!!!

I have seen this done by big name tuners. cough

[N0DIH]

It is in the LS1 and 3100/3400/3800 too, Adaptive Spark Multiplier. It is in %, but it is a % between the low octane and high octane table. Contrary to most belief's the high/low octane table makes up a 3D map, and the Adaptive Spark Multiplier makes up a new "3D map", as it tries to keep towards the high octane "upper limit" and the low octane is the "lower limit" of this virtual adaptive table.

I think Cadillac did it differently, a Calculated Octane Number IIRC. Then probably fed the ASM or it was the ASM.

Is that what you were talking about?

Originally Posted by AJxtcman

Just so we all understand!

I can change the following on a Northstar PCM as described by HPTuners Definitions

1. Gear Ratio
2. Shift Points
3. Air/Fuel Ratio
4. RPM Limiters
5. Timing Advance

The Timing Advance I need to spend more time on. I think I need to look for a 3rd table. I never thought about a 3rd table until another member posted some info on Octane Level Displayed
Take a look at this
GM > Engine > Spark Control > Spark Advance