Who can give us a lesson about tuning?

This is a question for my own benefit and for anyone else that wants to follow along.

When and why would you want to “get a tune”? My understanding is that this is done to override factory ECM/ECU settings in order to compensate for modifications to a closed loop system. Would I benefit from an aftermarket tune because I install a header, different air intake, etc.? Or is this for when you go with S/C or turbo on an otherwise stock engine?

Do people get tunes to deal with re-gearing, big tires and such?

Is the tune, in any case, done to protect the engine’s longevity or is it only done with performance in mind?

Thanks in advance for any knowledgeable input!

 

Factory tunes are for emissions and fuel economy as priorities. Tunes push timing and fuel trims to levels that aren't optimal for catalyst operation typically.

Often there is consideration for driveline wear and emissions with take off, so some manufacturers actually limite throttle % to 50% on take off till 15mph etc..

Fuel cools combustion so running richer with higher performance items is desired too.

Typically noticeable gains are only seen on forced induction or large mods like cams/injectors etc.

I'm not a tuner but I used to work with them.

 

Thanks for the information!

 

@JustDSM would be the guy to ask.
He actually tunes these trucks.