Koffel 451 motors ran 10.0's over here in the early 80's (same as the later "Rossi" car), in your average for then 3000lb+ race cars and cost approx £5000. Think they were .043" top ring motors with mega ported 452's, .750 rollers, big CR. Most got the s*it blown out of them as their owners put N20 at them, rather a silly/expensive move!!