Great vid ...I'm going to watch it again after this post :)
Back from the early to mid 1960's my best buddy and his dad, with some modest help from me, built a Henry J gasser, 292 straight 6 with a bunch of home made or low bucks parts and it usually ran H/Gas mostly at Atco NJ, sometimes Vargo and a couple other local tracks. Very often we'd take the class trophy and with a bit of luck, a couple eliminator trophies ...the exception being when the EMPI VW showed up and they usually creamed the Henry J. They ran almost 3 seconds faster et's! But we didn't care too much since it was just too much fun.