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PCM question

tmf6902

By tmf6902
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tmf6902 Senior Enthusiast

tmf6902

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When GM comes out with an engine they are going to put into their cars and trucks, how do they determine the computer parameters that go with it (PCM settings)? Do they throw it on an engine dyno, and configure it for the best optimal mix of power and mpg? Do they do it mathematically, with the known specs of the engine, and then throw it on the dyno to really optimize it?

 

Also am I correct to assume, every 8.1L truck with an Allison transmission for example; comes with the same exact flash on it's PCM?

redvett Senior Enthusiast

redvett

Posted
Posted
When GM comes out with an engine they are going to put into their cars and trucks, how do they determine the computer parameters that go with it (PCM settings)?  Do they throw it on an engine dyno, and configure it for the best optimal mix of power and mpg?  Do they do it mathematically, with the known specs of the engine, and then throw it on the dyno to really optimize it?

 

Also am I correct to assume, every  8.1L truck with an Allison transmission for example; comes with the same exact flash on it's PCM?

 

 

 

 

Gm starts off with dyno testing to get a baseline for the platform they will use the engine in. Then they will build real vehicles and test & doccument data. After that they will test production vehicles and make final calibrations. Then is off to the EPA for testing and certification. Production can then begin 2-3 years later. All engines in a family have different calibrations for different GVW,tire size & axle ratio and in some cases emissions for certain states.

Its a long process from start to finish.

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