450/455 SBM Purpleshaft

I ran it for years in my 340 Barracuda. Not terribly impressed. Just with a Wieand Action Plus, Holley 1850 and stock AVS carb, hipo manifolds, stock converter, original “advertised 10:1” pistons, 3.23 gears. All highway got about 14-16 mpg out of it going across country