By The Numbers
'70 Pontiac Trans Am
Steve Coombes, 60
Liberty Hill, TX

Engine
Type: Pontiac 505
Block: IA2 aftermarket block,
bored to 4.350 inches
Oiling: Melling oil pump, Canton six-quart pan
Rotating assembly: Crower 4.250-inch billet crank,
Eagle 6.800-inch big-block Chevy steel rods,
forged 10.0:1 JE pistons
Cylinder heads: Edelbrock Performer RPM
aluminum castings ported to flow 330/250 cfm
at .700-inch lift, Ferrea 2.15/1.77-inch valves
Camshaft: Crower 260/266 at .050 solid roller,
.701/.680-inch lift, 110-degree LSA
Valvetrain: Crower offset lifters,
Sims Performance roller bearing retainer plate,
T&D shaft-mount rockers
Induction: Edelbrock Victor intake manifold,
Holley 950-cfm carb built by Precision Racing Components
Ignition: MSD Pro-Billet distributor, coil,
and Digital 6 box; Taylor plug wires
Fuel system: Aeromotive A1000 pump,
Mallory five-port pressure regulator,
Jaz 16-gallon fuel cell
Exhaust: Hedman 2-inch headers,
Dr. Gas 3.5-inch X-pipe collectors,
dual DynoMax 3-inch mufflers
Cooling: Meziere water pump,
aluminum crossflow radiator,
dual Perma-Cool electric fans
with custom shroud
Output: 642 hp at 6,000 rpm
and 640 lb-ft at 4,600 rpm
Built by: CHS Racing Engines (Austin, TX)
Drivetrain
Transmission: GM TH200-4R trans,
3,500-stall converter,
B&M Quicksilver shifter,
Earl’s trans cooler
Rear axle: GM 12-bolt rearend,
Moser 30-spline axles,
3.73:1 gears, Auburn posi
Chassis
Front suspension: Global West upper
and lower control arms,
Edelbrock shocks, custom 1-inch sway bar,
Moog six-cylinder replacement springs
Rear suspension: Landrum 300 lb/in leaf springs,
Edelbrock shocks,
CalTracs traction bars,
custom subframe connectors
Brakes: Wilwood 10.75-inch discs, front;
Wilwood 11-inch discs, rear
Wheels & Tires
Wheels: American Racing Torq-Thrust D
15x6, front; 15x8.5, rear
Tires: Firestone 215/65R15, front;
Nitto 275/60R15 drag radials, rear