We rebuilt the 260 in the Tiger we have we used a comp cams kit, roller rockers an F4B manifold, and a 600 cfm carb we bored the motor 030 over and used ARP rod bolts( couldn’t find a set of 289 rods ) I’d say it was well worth the effort the car is pretty quick for what we did $ wise, probably on par with the 302 Alpine we had. just my o2s, go your own way is the motto here.