A 283 is a totally different animal. The 305 has close to a 265 bore, and a 350 stroke. That translates to lots of low end torque, but nowhere near the 8,000+ RPM capability of the 283. Gear it high, and keep the RPM down to a reasonable level, and the 305 is a good choice. Just don't get crazy with the top speed before you shift.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
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