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15 Dyno-Proven Horsepower Combos

Rear-Wheel Dyno Combos

Photography by Marko Radielovic

Oldsmobile V-8: Mild

Car: '66 Oldsmobile Cutlass
Owner: James Selby

Oldsmobiles are all about torque, and James Selby's Cutlass is no exception. A frequent participant in the Street Machine Nationals series burnout contests, James' Olds always produces prodigious amounts of tire smoke seemingly effortlessly. The 11:1 compression seems high, but the long-duration Comp Cams camshaft bleeds off enough cylinder pressure to safely run on pump gas. Featuring a gasket-matched but otherwise stock set of "C"-casting cylinder heads, an Edelbrock Performer intake, and an Edelbrock 850-cfm Quadrajet, James' behemoth is still able to knock down low-12-second quarter-miles. And it does great burnouts!

Engine

Type: Oldsmobile V-8
Displacement: 461 ci
Compression: 11:1
Best e.t.: 12.29 @ 110

Heads

Make and model: Production iron "C" castings
Port work: Gasket match
Valve sizes: 2.08/1.68
Rocker arms: 1.6:1 roller

Camshaft

Make: Comp Cams
Type: Hydraulic flat-tappet
Duration at 0.050: 244 degrees
Valve lift: 0.518 inch

Induction, Ignition, and Exhaust

Intake: Edelbrock Performer
Carburetor: Edelbrock Quadrajet 850 cfm
Ignition: GM HEI distributor and MSD 6AL
Exhaust: 1 ¾-inch headers, 2.5-inch dual exhaust

Performance

Owner's guess: 315 hp
Dyno result: 296 hp, 412 lb-ft

Mopar Big-Block: Mild

Car: '68 Plymouth Roadrunner
Owner: Bob Gossen

Bob Gossen of Stacy, Minnesota, chose Chrysler's venerable 440 torque monster to power his portly Roadrunner. Using Mopar Performance's tried-and-true 509 juice cam, a pump-gas friendly 10:1 compression ratio, ported smog-era production cylinder heads, an Edelbrock Performer RPM intake, and a 750-cfm Holley fuel mixer, Bob was able to squeeze out an eager 340 horses at the wheels. The torque topped out at 400 tire-melting pound-feet.

Engine

Type: Chrysler big-block V-8
Displacement: 440 ci
Compression: 10.0:1
Best e.t.: Unknown

Cylinder Heads

Make and model: Production iron "452" castings
Port work: Fully ported
Valve sizes: 2.14/1.81
Rocker arms: 1.5:1 stamped steel

Camshaft

Make: Mopar Performance
Type: Hydraulic flat-tappet
Duration at 0.050: 248 degrees
Valve lift: 0.509 inch

Induction, Ignition, and Exhaust

Intake: Edelbrock Performer RPM
Carburetor: Holley 750 cfm
Ignition: MP electronic distributor with orange control box
Exhaust: 1 7/8-inch headers, 3-inch dual exhaust

Performance

Owner's guess: 345 hp
Dyno result: 340 hp, 400 lb-ft

Chevy Big-Block: Moderate

Car: '67 Chevy Chevelle
Owner: John Sinna

Conventional wisdom among Rat-motor aficionados on the street is that the production oval-port heads are superior to the gargantuan rectangular-port offerings. John Sinna chose Chevy's oval-port castings with minor bowl porting, a Crower solid grind, and 9.8:1 compression to produce 409 hp and 443 lb-ft of torque. A streetable RPM Air Gap intake manifold further contributes to his Chevelle's street manners. Are oval ports better on the street than rectangular ports? That depends on the combination of parts and the purpose of the motor. We can safely say that John Sinna has created a very effective Rat motor using oval-port heads.

Engine

Type: Chevy big-block V-8
Displacement: 468 ci
Compression: 9.8:1
Best e.t.: Unknown

Cylinder Heads

Make and model: GM production iron oval-port castings
Port work: Pocket ported
Valve sizes: 2.10/1.88 inches
Rocker arms: 1.7:1 roller

Camshaft

Make: Crower
Type: Solid flat-tappet
Duration at 0.050: 292 degrees advertised duration
Valve lift: 0.625 inch

Induction, Ignition, and Exhaust

Intake: Edelbrock Performer RPM Air Gap dual-plane
Carburetor: Demon 850-cfm Speed Demon
Ignition: GM HEI distributor
Exhaust: 2-inch headers, 2.5-inch dual exhaust

Performance

Owner's guess: 440 hp
Dyno result: 409 hp, 443 lb-ft

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