[joedeats]

I would think that combination would create a very negative rod ratio, if we look at the math for a 427w motor we would have a rod of 6.00 and a stroke of 4.170 so 6.00 divided by 4.170 nets you a rod ratio of 1.438. This is a very short ratio 1.8 is considerd optimal for all around power but a short ratio has alot of negatives.They are an increase in piston speed away from TDC which, at very high RPM, will out-run the flame front, causing a decrease in total cylinder pressure (Brake Mean Effective Pressure) at the end of the combustion cycle. Due to the reduced dwell time of the piston at TDC the piston will descend at a faster rate with a reduction in cylinder pressure and temperature as compared to a long-rod motor. This will reduce total combustion.
And finally the worst part much increased wear due to elevated piston speeds which for your 427w combo would be 40.5 ft per sec at 3500 rpm as compared to 347/302 combo would be 33ft per sec. Just for information the 460 has a 1.72 stroke ratio near ideal. For your 427w combo to be optimal you will need Large intake port volume vs. motor size, Single-plane or 360° intake manifolds
(Edelbrock Victor, Torker & Torker II, TM7. Holley Strip Dominator. Offenhauser Equa-Flow, Port-O-Sonic. Weiand X-Celerator, Team G), Large carburetor vs. engine size, Moderate engine speed
NO high RPMS, and a Tall axle ratio.