2000 Pontiac Firebird MMS 421 Concept


2000_Pontiac_FirebirdMMS421Concept1

2000 Pontiac Firebird MMS 421 Concept

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 by Richard Owen
displacement 6899 cc / 421.0 in³
bore 104.77 mm / 4.12 in
compression 11.7:1
power 466.1 kw / 625.0 bhp
specific output 90.59 bhp per litre
bhp/weight bhp per tonne
torque 745.7 nm / 550.0 ft lbs
front tires 295/35-ZR18
rear tires 295/35-ZR18
f brake size x 356 mm / x 14.0 in
r brake size x 356 mm / x 14.0 in
front wheels F 45.7 x 25.4 cm / 18.0 x 10.0 in
rear wheels R 45.7 x 25.4 cm / 18.0 x 10.0 in
gear ratios :1