I continue to read about this "Performance Shift Mode" that the PCM in the W-Body style Pontiac had. I'm looking at the PCM upgrades and read about grounding pin 21 on the PCM to enable this feature. I'm wondering if our MC's have this feature and if it can be done with the stock PCM. It says in 2001 Pontiac removed the feature from it's vehicles and all the others never had it to begin with. They then go on to say that by grounding pin 21 it will enable this feature. Can this be done on a stock PCM?

 

I don't even think it matters anymore. All it really did was allowed the car to shift 500 RPM's higher than normal. You can get a DHP PCM replacement that will do better than that.