79 Bob Glidden Small Block Pro Stock

Hello - I usually post over on the Early A-Body forum but I came across this crankshaft so I felt I should ask here. I have been cleaning out my brother's home after his death last year. He was a real Mopar guy and had couple of small block race cars, a 66 Valiant and a Duster Pro Stock chassis that he ran a 340 in Super Stock back in the early '80s. So I came across this crankshaft in his shed marked "340 3.250 stroke, 2" rod journal, Bob Glidden 79 Pro Stock" so I looked up Bob Glidden's successful '79 Plymouth Arrow that did indeed run a small block.

So I'd like to understand why he would run a de-stroked small block? Anybody know about his Mopar engine program? It's an interesting piece, in any case.