All for .370 lift and under ........

"controlled by your right foot...." Exactly !!! We know our gains will be small, but the van is a keeper so we wanted to freshen up the heads anyways... besides, I don't want to lose too bad to the Hoosier Garage Van :D :D
Your gain is probably to the valves sealing again. Check my other post on camshafts. You could step up if you decide to upgrade the cam to a retrofit roller. The advantage is oil selection. With flat tappet cams now, the Zinc and Phosphorus content must be checked. Basically a 10W30 diesel oil.
I have my 289 Ford apart and the cam and lifters are showing signs of wear from using shelf oil before the removal of ZDDP was known about. I have the Engle cam from my 351 with low miles and in good shape I will put in. This is in a 1940 Ford Fordor, so probably not the most aerodynamic. I will be using diesel synthetic oil in it to protect the cam and lifters..