IMO, yes and run a pan with a seal. The 340 was in when I put the hood on, it picked up but honestly I don't remember how much.

My Dart has a A&A six pack hood on it and I've had three small blocks in it in the last 12-13 years and all have ran better sealed up. I did back to back tests on the 408 and the 434 with and without the pan. The car lost et everywhere, even 60', it may have been different had I messed with the jetting for no pan.

On another note my car runs cooler on the street without the pan.