I had a 358 (3.295 stroke 4.155 bore) in a 1969 Firebird. It did pretty good on nitrous, but was not the most impressive on motor alone. It dynoed at 608 hp at 7900 RPM but only had around 460 ft lbs, cant remember for sure what RPM that was at . The car weighed 3150 with the driver. 1/8th mile, it ran a best of 7.12 on motor and 6.29 on a 100 shot. That was with a glide, 4.88 gear, 28" tall tire and a 5000 stall. I think it would have run better and been easier on parts (valve train at least) to just build a 406.