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.

In Detail

submitted byRichard Owen
displacement6899 cc / 421.0 in³
bore104.77 mm / 4.12 in
compression11.7:1
power466.1 kw / 625.0 bhp
specific output90.59 bhp per litre
bhp/weightbhp per tonne
torque745.7 nm / 550.0 ft lbs
front tires295/35-ZR18
rear tires295/35-ZR18
f brake sizex 356 mm / x 14.0 in
r brake sizex 356 mm / x 14.0 in
front wheelsF 45.7 x 25.4 cm / 18.0 x 10.0 in
rear wheelsR 45.7 x 25.4 cm / 18.0 x 10.0 in
gear ratios:1

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