355 Throttle Response

Have put several hundred miles on my new to me 355 spider. After sorting through the bad cat, bypass valve etc. the car is running great. No codes or CEL lights! Thanks to all for their help.
I have noted a couple of differences between the 355 and my 348 spider. Just want to see if they are normal or indicators of another problem.
Throttle response in the 355 5.2 does not seem as crisp as my 348. I still double clutch on downshifts(old habit!). When I blip the 348 throttle the response is an immediate rise in rpm’s. The same action in the 355 is muted/ flat, almost no change in RPM. Almost feels choked. Car is at operating temperature.
Speaking of choked. When the car is cold and initially driven the car feels like an old choked carb car. Flat and not responsive. Once warm, acceleration and throttle response markedly improve. The exception is the lag noted when the throttle is blipped as I detailed earlier.
If the performance I have described is normal, no problem. The car is an absolute blast to drive! If not I need to research the problem and correct.
355 is a ’97 5.2 model. Last major a year ago by FoW. PPI detailed strong compression and leakdown numbers. Techs driving impression was a strong performing 355. Stock cats(as new condition) and Ferrari Challenge exhaust.
Opinions welcome, thank you.