Rover engine VS Stag engine?

[<BUZZ52490@domain.elided>]

I am at the point where my Stag needs much work. I like performance and not
into concours events although like mint cars.Should or shouldn't I change my
engine? What should i put in? Its been sugested that a Tr8 engine would be a
great move .Any input is welcome Dennis New York City 1971 Stag