I will be making some dyno runs in the next few weeks and had some
questions regarding the time it takes for the engine to adjust after
a PCM swap. I have the original PCM with a HPP tune and a used PCM.
The plan is to get a mail order tune on the used PCM and then do two
or three pulls with each. Both PCMs are 97.

Will I get optimum results if I swap the PCM between pulls?

Should I schedule the dyno pulls with each PCM separately? If yes, how
many miles should the car be driven to adjust?

 

Im not sure if it will affect perfromance, but when you unplug your battery or PCM your OBD2 rediness monitors reset. There is a certain drive cycle to go through that will complete them all, but probably nearly impossible to complete on the street. There is alot of other factors also, such as your tank having to be between 1/4 and 3/4 full, certain outside temp, and a bunch of other stuff. The rediness monitors are mainly for emissions control, so Im not sure how they will affect performance. Just something to think about.

 

I have scanned through the service manual for info on PCM removal and
replacement but have not found anything regarding a run in period. I still
need some advise from those of you that have experience with this.