1970-'72 W-30 455 Oldsmobile

When GM repealed its 400-cubic-inch limit on its mid-sized models for 1970, it finally leveled the playing field with Chrysler and Ford, and Oldsmobile was prepared for battle. Its 455-cu.in. engine, which was introduced in 1968 and featured in the Hurst Olds, Toronado and full-size models, became the standard 4-4-2 powerplant, rated at 365 hp. Opting for the W-30 "W-Machine Package," however, would provide significant additional benefits.

Available first in 1966 on the 400-cu.in. Tri-Carb 4-4-2 and continuing with a four-barrel thereafter, the W-30 was a comprehensive go-fast option package. For 1970, with 55 more cubes on tap, the Force-Air-inducted W-30 455 was rated at 370 hp at 5,200 RPM and 500-lb.ft. of torque at 3,600 RPM.

The two-bolt main block has a 4.125-inch bore and the nodular-iron crank a 4.250-inch stroke. Forged-steel 6.735-inch connecting rods are pinned to aluminum alloy pistons. "Select-fit" engine parts in Olds-speak meant that those for the W-30 were chosen from specific groups to attain the most advantageous weight match and clearances.

For four-speed cars, the aggressive #402569 cam features 328/328-degrees advertised duration and .475/.475-inch lift. The #400165 cam was for the automatic-equipped W-30 and has 285/287-degrees duration with .472/.472 lift. Inside the refined F-casting (H-1971 and Ga-1972) cylinder heads are 2.072/1.625-inch valves, and heavy-duty valve springs and 1.60:1 shaft-mounted rocker arms were used. The compression ratio is 10.5:1.

Oldsmobile replicated the stock cast-iron intake manifold in aluminum to reduce weight for the W-30, and the Quadra-jet carb and Delco breaker-point ignition system were dialed-in to the package. Cast-iron exhaust manifolds flow into 2.25-inch head pipes, twin mufflers and 2.00-inch tailpipes, and the exhaust system ends in chrome trumpet tips that peek through cutouts in the rear bumper. A six-blade clutch fan was also added.

The W-30 included additional components to further exploit its capabilities and add style. The Force-Air-inducted dual-scooped and wide-striped W25 fiberglass hood with chromed tie-downs lops off pounds and directs cold outside air to the hungry carb via an air-cleaner assembly that's sealed to it. Reduced sound deadener saves more weight, and body side stripes and W-30 emblems draw attention, and so do red plastic inner fenderwells, as shown here on Ed Pienta's 1971 W-30 4-4-2.

Mandatory options include an M21 close-ratio four-speed with Hurst shifter or a performance-calibrated M40 Turbo Hydra-Matic 400 with a special torque converter; the G92 Performance Axle Package with 3.42:1 gears (or G88 with 3.91:1 gears), Anti-Spin and heavy-duty radiator (steeper rear gears could be dealer installed); PK5 G70-14 raised white letter bias-ply glass-belted tires and body-colored sports-styled mirrors with remote controlled driver side.

An optional W27 aluminum rear axle carrier and cover saved about 22 pounds. The W26 Hurst-Dual Gate shifter in the sport console was also available at extra cost.

Unlike the W-30 400s that came before it, for 1970, A/C was available, but only with the M40 trans, power brakes and 3.23:1 gears.

Since the W-30 was an option for the 4-4-2, the famed FE2 suspension and 14 x 7-inch wheels were already included. Manual front disc brakes were standard on the W-30. Power assist was available only for automatic-trans W-30s.

The W-Machine Package was offered in the 4-4-2 Holiday coupe, sports coupe (post) or convertible, and total cost was $369.68, including W-30 at $321.23, D35 mirrors at $22.12 and PK5 tires at $26.33.

What was it worth on the drag strip? Car Life ran the quarter-mile in 14.36 at 100.22 MPH in a 1970 4-4-2 W-30 with an automatic and 3.42:1 gears, two people aboard, test equipment and a 4,195-pound test weight. Hot Rod ran 14.10 at 100.55 MPH in street trim with its W-30 test car featuring the automatic and 3.91:1 gears.

For 1971, there were mechanical changes. Most notably, the compression ratio dropped to 8.5:1 to meet looming federal emissions regulations to ensure engines could run on low-lead, no-lead or regular fuel.

According to Oldsmobile's Engine Assembly Manual, the W-30 four-speed cam was tamed to #409759 with 294/296-degrees advertised duration and .472/.472-inch lift. For the automatic, it became #409691 with 286/287-degrees duration and .474/.472-inch lift and #400165 was employed for the W-30 with the automatic and A/C and measured 285/287-degrees advertised duration with 472/.472 lift.

Net power ratings were being adopted industry-wide and provided a more accurate measure of engine output by dyno testing them while outfitted with the accessories--air cleaner and alternator etc.--that would be on them when installed in the actual car. As a result, the W-30 455 was rated at 350-hp gross and 300-hp net and torque was 460-lb.ft. gross and 410-lb.ft. net.

The W-30 Performance Package included much of the same equipment and mandatory options as in 1970, and the four-speed or the automatic transmission was once again mandatory. For 1971, however, a wide-ratio M20 four-speed was added and the close-ratio M21 four-speed was replaced with the famed close-ratio M22. The 3.90:1 rear gear choice was reduced to 3.73:1 but the other previous year's gear choices remained.

Dropped from the line was the 4-4-2 sports coupe (post). Cost for the W-30 Performance Package in 1971 was $369.67 without power brakes, $347.56 with them. The W27 option was reduced to an aluminum differential cover, foregoing the aluminum carrier of the previous year.

For 1972, the W-30 (L77) retained its 300 hp at 4,700 RPM and 410-lb.ft. of torque at 3,200 RPM ratings, but was not available in California. The M22 close-ratio four-speed was dropped, leaving the wide-ratio M20 and the M40 Turbo Hydra-Matic as the only choices.

The 4-4-2 reverted back to option status. Thus the W-30 Performance Package included the items of previous years, as well as the new W29 4-4-2 Appearance and Handling Package, which added the FE2 Rallye Suspension, wheel opening moldings, 4-4-2 grilles and emblems, and any striping that didn't conflict with the W-30.

Since the 4-4-2 was no longer its own model, the W-30 was available on the Cutlass Holiday coupe, Cutlass S sport coupe and Holiday coupe and the Cutlass Supreme convertible (and the Hurst Olds). Including the previous year's items, plus the W29 4-4-2 option and G80 Anti-Spin rear, the W30 Performance Package cost $719.34 with power brakes and $741.45 without, on the Cutlass. On other models, it was cheaper.

Though the cam specs for the four-speed and automatic W-30s were carried over, A/C was not available with the W-30 in 1972, which negated the need for the A/C cam and the 3.23:1 rear gear that had come with it the previous year. The red plastic inner fenderwells were also discontinued.

Super Stock Magazine tested a W-30 4-4-2 with an automatic trans and 3.42:1 rear end and ran a best of 14.47 near 100 MPH.

As can be expected for a purpose-built machine, production numbers for the W-30 4-4-2s are quite low. For 1970, 3,100 W-30s were built. Additionally, Oldsmobile assembled two W-30 Vista Cruiser wagons. Sales receded to 920 W-30s for 1971 and just 772 for 1972.

The reputation that the W-30s cultivated for potent yet sophisticated performance has reached much further than the model's low production volume would suggest and they remain highly coveted and collectible muscle cars. Though W-30s were offered before 1970 and the name was employed again sporadically after 1972, 1970 represents the zenith for power and the depth of the available package components and options, and the 1971 and 1972 versions weren't that far behind. They stand as remarkable reminders of a bygone era when the 455-based W-30 excelled in acceleration without compromising all else...too much.

Special thanks to Fred Mandrick.