race gas or pump gas

1977 Datsun 280z built 383 small block Chevy engine, forged Pistons and rods, racing steel stroker crank, big 208 valves, 950 cams, comp cam summit racing headers, Holley carb, high rise intake, moroso rockers and griddle lock,
Dual side pipes, Muncie 4 speed transmission, hurst shifter, diamond plates floor pans, 41" ladder suspension, ford 9" rear end, 411 posi true trac differentials, tubed chassis, fuel cell, wilwood brakes, street legal. 500hp/498tq. With a compression of 13.5....


So these are the stats for my car, so I have a question for the masses, the former owner has suggested I run 112 oct. racing fuel in it, where as I would like to drive it more on the regular, would like to run 91-93 octane in it. So would running the lower octane harm the engine, I understand the lower octane would decrease the get up and go but would it cause under just normal freeway conditions undesired pinging or knocking? Please and thank you... /\

You would likely need to make timing adjustments to adjust for the lower octane to avoid knock.

What cyl heads, what compression ratio, what are the cam timing events, rocker arm ratio?