1" Carb spacer

I recently threw a 1 inch spacer/adapter in between my performer rpm with a spread bore opening, and my Holley 4 barrel with square bore holes (duh) The adapter I used is open style and so far from what I can tell, it seems a little harder to start so I need to feather the throttle for about 30 seconds on cold starts and once warm the idle is a little rougher than before, but at speed it seems to respond better at any point above 25mph. I also have a 4 hole adapter that I will be trying in the coming weeks to see if I notice any difference.
I am not sure how "scientific" this is because I admit I am not the greatest of achieving the perfect tune and I am only using a butt dyno.
FYI, my carb still fits fine under the stock flat hood but my old circular 14"x3" pie pan air filter no longer fits due to it contacting the bracing under the hood, I knew this going in but I still think its worth mentioning