Oldsmobile Cutlass Rallye 350

Rallye 350 at a glance: maker, year and purpose

By 1970 the American muscle car was squeezed from three sides: tighter emission rules, rising fuel prices and, above all, insurance premiums that young drivers could hardly afford for big-engined cars. The Rallye 350 answered with a mid-size Oldsmobile that looked as loud as any muscle car but carried a smaller V8. That made it cheaper to buy and insure than a 4-4-2 with its 455 cu in engine.

The old 1cars text described Oldsmobile's early history and the general Cutlass engine range (a 250 cu in six and 350, 400 and 455 V8s). That range belongs to the Cutlass line as a whole; the Rallye 350 itself came only with the 350 V8.

A one-year package: production by body style

The Rallye 350 was introduced for the 1970 model year as an appearance and performance package, not a separate model. It could be ordered on the cheapest F-85 Club Coupe, the Cutlass Sport Coupe and the Cutlass S Holiday Coupe hardtop. Because it was an option, the Vehicle Identification Number does not show it, which matters for collectors today.

Oldsmobile did not repeat the package in 1971. Its loud styling divided dealers and buyers. A widely repeated story says that some dealers fitted chrome bumpers and vinyl roofs to make unsold cars less yellow. At least one such car, first sold in San Jose, California, is documented, although the practice was rare.

Design: Sebring Yellow everything

What made the Rallye 350 stand out was its colour. Body, front and rear bumpers, mirrors and wheels were all Sebring Yellow; the bumpers had a urethane coating in body colour instead of chrome. Black and orange sport stripes ran over the bonnet, sides and tail, and "Rallye 350" decals sat on the rear quarters. The grille was blacked out.

Other parts of the package:

• the W25 fibreglass Force-Air bonnet with two functional scoops;
• an optional W35 rear deck spoiler;
• yellow-painted Super Stock II wheels, 14 by 7 inches, with G70-14 bias-belted tyres;
• Rallye-Sport suspension with stiffer springs and anti-roll bars front and rear.

Inside, the cars were standard Cutlass or F-85, with bench or bucket seats depending on the body and options. The speedometer reads to 120 mph and the optional Rally Pac adds a rev counter. The boot is large for a coupé but shares space with the full-size spare wheel, as the old article noted.

L74 Rocket 350 and gearbox choices

The L74 is Oldsmobile's 350 cu in Rocket V8 (5.7 litres) in high-compression form, with a 10.25:1 compression ratio, a Rochester Quadrajet four-barrel carburettor and cold-air induction through the bonnet scoops. Oldsmobile rated it at 231 kW (310 hp) gross at 4,800 rpm and 390 lb-ft (529 Nm) at 3,200 rpm.

Gearboxes:

• three-speed manual, standard;
• four-speed M20 wide-ratio manual, optional;
• three-speed Turbo-Hydramatic 350 automatic, optional, with a column shifter or a Hurst Dual-Gate console shifter.

The standard 12-bolt rear axle had a 3.23:1 ratio, with 3.42:1 and 3.91:1 options and an anti-spin limited-slip differential. Power front disc brakes were optional, and air conditioning was available only with the standard 3.23 axle. The old 1cars text gave only the automatic gearbox; in fact most buyers could choose from three.

Performance

In its May 1970 test, Car Life ran a four-speed Rallye 350 with a 3.42 axle through the quarter mile in 15.27 seconds at 94 mph. The magazine summed it up as a car where "beneath the gaudy paint and wing lurk bargains in performance and handling". That was slower than a 4-4-2 W-30, but close to many big-block cars of the time once they wore street tyres.

Rallye 350 specifications

With 231 kW in a body of about 1.6 tonnes, the Rallye 350 has roughly 144 kW per tonne by our calculation. That compares with about 160 kW per tonne for a 1970 4-4-2 with the 272 kW (365 hp) 455 engine and about 1.7 tonnes. The power-to-weight calculator repeats the sum for any car.

Rallye 350, W-31, 4-4-2 and Hurst/Olds compared

Among rivals from other GM divisions, the closest in spirit were the Pontiac GTO "The Judge" and the Chevrolet Chevelle SS; you can compare them with the Cutlass family using the 1cars comparison tool.

What came after the Rallye 350

The Rallye 350 did not save the small-block muscle car: within two years, emission rules and net power ratings cut outputs across the industry. Yet the Cutlass line went on to its best years. It became Oldsmobile's best-selling line in 1975 and reached a record 632,742 cars in 1977. Production ended on 2 July 1999, after which the Alero replaced it. Oldsmobile itself closed in 2004, a story told in the history of Oldsmobile.

Buying and collecting a Rallye 350 today

Rallye 350s are rare and easy to recognise, but also easy to fake, because a yellow Cutlass can be painted to look like one. Since the VIN does not record the package, authentication depends on documents: the original window sticker, the build sheet or a sales receipt. The cowl tag paint code 51 is a first check.

Further points:

• urethane bumpers crack and fade; correct reproductions exist, but original parts add value;
• check the fibreglass bonnet for cracks around the scoops;
• confirm the engine is a correct L74 350 for 1970;
• rust in the rear window channel, floor pans and lower rear quarters is common on A-bodies.

Values rose steadily in the 2010s and 2020s, with four-speed Holiday Coupés the most sought-after. The Rallye 350 is the choice for a buyer who wants a documented, rare muscle car with lower running and insurance costs than a big-block 4-4-2. More cars of the period are in the 1970s classics section.