Well Kevin, I do expect the torque curve will be impressive and about as flat as the Kansas prairie and it'll start just off idle, however I'm guessin' just by looking at this Max Horsepower rating and where its rated, that the redline sounds at if it'll be at just about 5000rpm. And if that's the case, I still can't see, even with these pretty large pistons, why this might necessiate this low of a redline figure???
I mean, with most modern engines running pistons with very shallow skirts, hence being a whole lot lighter in weight nowdays, I can't imagine why there would be any concern here of the reciprocating weight of the pistons and/or the piston speed involved to be enough to limit this engine to such a low RPM figure? And, you certaining don't have to worry about the reciprocating weight of any pushrods here either!
(hey, here's a thought...maybe it would've had a 7000rpm redline IF they'd have given it more FINS around the cylinder barrels???!!!

.....sorry)