One HP per cubic inch with the 250 is not impossible, just difficult and very expensive. You can forget about using that HP figure and "daily driver" in the same paragraph. Very high compression, a roller cam, major cylinder head modifications, and a pretty exotic fuel system such as three side draft Weber carbs or fuel injection will be pretty much required, as well as split headers and dual exhausts, and a redline RPM of 6,000 or more. Bring a wheelbarrow for the dollars!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
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