Morgan Motorsports put together this 2001 Trans Am MMS 421.
The parameters set down were that the power would have to 1) come from natural aspiration – no turbocharger, supercharger or nitrous oxide in use here, and 2) be in the output range of 600 horsepower. No small feat, indeed.
Starting with a sleeved block resulting in a 4.125 bore the MMS team installed a SCAT billet crankshaft. ROSS 2618 alloy pistons sit atop Callies forged I-beam 6.125 rods.