The Chevrolet Monza is a subcompact, four-passenger automobile produced by the Chevrolet division of General Motors for the 1975–1980 model years. The Monza is based on the Chevrolet Vega sharing its H platform and 140 CID inline-4 engine. The 1975 Monza 2+2 was designed to accommodate the GM-Wankel rotary engine, but due to mediocre fuel economy and emissions compliance issues the engine was cancelled, and a fuel-efficient 4.3 liter V8 engine option was substituted.
Motor Trend awarded the Monza 2+2 V8 1975 Car of the Year. The Monza 2+2 and Monza Towne Coupe competed with the Ford Mustang II and other sporty coupes. A total 731,504 Monzas were produced in six model years. GM H-body variants Buick Skyhawk and Oldsmobile Starfire were produced using the Monza 2+2 body with grill and interior trim variations and Buick's 3.8 liter V6 engine. The Pontiac Sunbird variant was introduced the following model year. The Monza nameplate originated in 1960 for the sporty version of the Chevrolet Corvair.
The Monza, Chevy's sporty successor to the Vega debuted as a 2+2 hatchback. The Monza is 4 inches longer and weighs 180 pounds more than the Vega from which it is derived. John DeLorean nicknamed it the Italian Vega citing styling with a strong resemblance to the Ferrari 365 GTC/4.
The 1975 Monza 2+2 was initially slated to introduce the GM Wankel rotary engine which is licensed from NSU. Notable rotary issues included mediocre fuel economy compounded at a time of comparatively high fuel prices following the Arab oil boycotts of 1973 and 1974, and GM canceled the engine. Thus the 1975 Chevrolet Monza was launched carrying conventional piston engines instead.
The 1975 Monza 2+2 featured newly approved rectangular headlights and a slot-style grille in a slanted nose made of resilient urethane. The side window louvers are functional, part of the flow-through ventilation system. The Monza 2+2's two-door hatchback body style was shared with the Oldsmobile Starfire and Buick Skyhawk. The standard Monza engine was the Vega aluminum-block 140 CID (2.3 liter) inline-4 engine with a single barrel carburetor generating 78 hp at 4200 rpm. (Monza S). The optional 2-barrel carburetor version generates 87 hp at 4400 rpm..
Chevrolet's new 4.3 liter (262 cid) V-8 engine was optional. The smallest V8 ever offered by Chevrolet, it features a Rochester 2-barrel carburetor and generates 110 hp at 3600 rpm. For 1975 only, Monzas sold in California and high altitude areas met the stricter emissions requirnment by substituting a version of the 5.7 liter (350 cid) V-8 engine with a 2-barrel carburetor tuned to just 125 hp. The Monza 2+2 and its Buick and Oldsmobile variants feature GM's first use of a torque arm rear suspension, also adopted for the 1975 Chevrolet Cosworth Vega introduced mid-1975, and later, all 1976-77 Chevrolet Vegas and Pontiac Astres. The basic design was also incorporated into GM's third and fourth generation F-bodies, Chevrolet Camaro and Pontiac Firebird.
In April 1975, the Monza Towne Coupe was introduced - a notchback body-style with a conventional trunk featuring different sheetmetal than the 2+2 hatchback, although sharing its windshield, front fenders, and doors. It features single round headlamps, instead of the dual rectangular headlamps on the 2+2. The Towne Coupe was offered in response to the sales success of the Ford Mustang II notchback coupe and its luxury version, the Mustang II Ghia. The Towne Coupe is 1.5 inches shorter and 135 pounds lighter than the 2+2 and has slightly more rear head room. A lower priced "S" version of the 2+2 Hatchback was introduced mid-year. It featured as standard the Vega 1-barrel engine with a 3-speed manual transmission. The sport suspension, full console, sport steering wheel, day/night and wheel opening moldings were deleted on the "S".
Stillborn Rotory EngineIn November 1970, GM paid $50 million for initial licenses to produce the Wankel rotary engine, and GM President Ed Cole projected its release in three years, initially targeted for an October 1973 introduction as a 1974 Chevrolet Vega option. The General Motors Rotary Combustion Engine (GMRCE) had two rotors displacing 206 cubic inches, twin distributors and coils, and an aluminum housing. RC2-206 Wankels were installed in 1973 Vegas for cold weather testing in Canada.
Motor Trend, in a 1973 article "The '75 Vega Rotary" said: "GM saw the rotary engine's future as probably much greater than they do today...mileage will be in the 16-18 mpg range. Compared to the normal piston (engine) Vega's 20 to 26 mpg, the whole rotary deal begins to look just a little less attractive, with what the price of gasoline skyrocketing, but that's another matter." Unwilling to face fuel efficiency criticism that Mazda withstood, GM felt it could meet 1975 emissions standards with the engine tuned to provide better mileage. Other refinements improved mileage to 20 mpg, but with the fuel breakthrough came related side-effect problems —apex seal failures, as well as a rotor tip-seal problem.
By December 1973, it was clear the Wankel, now planned for the Monza 2+2, would not be ready for either production or emissions certification in time for the start of the 1975 model year, and after paying another $10 million against its rotary licence fees, the company announced the first postponement. Motor Trend in April 1974 predicted the final outcome – on September 24, 1974, Ed Cole postponed the Wankel engine ostensibly due to emissions difficulties. He retired the same month. GM admitted fuel economy for the rotary was sub-standard and postponed production in favor of further development. Pete Estes succeeded Ed Cole as GM President and never showed any special interest in the Wankel or in the perpetuation of Cole's ideas. Estes had previously decided to let the Corvair, another Cole project, expire well before the celebrated attacks of Ralph Nader.
Car of the Year
The Chevrolet Monza 2+2 V8 emerged as Motor Trend's 1975 Car of the Year from a long, tight and difficult contest that involved the opinions of scores of people, nearly impossible logistical problems and a selection process unprecedented in the 25-year history of the award. In July 1974, Motor Trend's staff selected 15 cars to vie for Car of the Year and Golden Wheel Award honors. The cars were then judged by a panel of 25 distinguished members of the automotive press. The Media Panel's selections went to the Car of the Year and Consumer Panels. The five Car of the Year finalists-Mercedes-Benz 450 SE, Ford Granada, Chevy Nova LN, VW Dasher, and the Chevy Monza were thoroughly wrung out by 13 people from two panels. The Monza emerged victorious from this crucible of expertise. "While the Monza did not clearly stand first in any of the five areas of judgement, our panel concluded that the V-8 Monza exemplified the best balance of all the judgement factors."
Model year changes
The 1976 140-cubic inch four-cylinder engine, as used in the Vega got some refinements. Named "Dura-built 140", it featured quieter hydraulic lifters eliminating valve adjustments. The basic four developed 70 horsepower, but two-barrel carburetion upped the rating to 84. 1976 saw the introduction of Chevrolet's new 5.0 liter (305 cid) V-8 engine with a 2-barrel carburetor generating 140 hp at 3800 rpm, but only for California and high-altitude Monza customers, and replaced the 350 CID (5.7 liter) V-8. The 262 V8 was again, the optional engine in the 49 states. A mid-year option for the 1976 model year was a sport front end available for the Towne Coupe, which features the 2+2's urethane front end and quad headlamps. The Monza Spyder option package was first introduced in 1976. It features a 2-barrel carburetor version of the 4-cylinder engine as standard, a floor console, F41 suspension with larger front and rear stabilizer bars, and special shock absorbers. This equipment had been standard on the original 1975 2+2 (excluding the mid-year 'S' model).
The 1977 Monza was highlighted by the addition of a two new Spyder option packages, a $274 performance package, the other a $199 appearance add-on package that was available only on hatchbacks. An 84-horsepower four-cylinder engine was standard, but Monzas could be ordered with a 145-horsepower 305-cubic-inch V-8 instead. The Monza dashboard contained round gauges in a brushed-aluminum instrument panel. The Towne Coupe Cabriolet was deleted, but a half-vinyl roof and opera windows could still be ordered. The Monza Mirage was produced by Michigan Auto Techniques contracted by GM. The Mirage is painted white, with red and blue racing stripes along the length of the car. It also features flared body panels, and a special airdam & spoiler. The vehicles were built in GM's St. Therese plant, and sent to MAT for modification, after which they would ship completed cars to the dealer. There were approx 4,097 1977 Mirages made from MAT but there were also Mirages created by Chevrolet dealerships, as the body add-ons and stripes were available ordered through dealer parts. The 5.0 liter (305 cid) engine was the only V8 option for the 1977 model year. The standard Vega 2.3 aluminum-block engine was discontinued at the end of the model year, replaced with the Pontiac 2.5 "Iron Duke."
The 1978 Monza line expanded to include re-badged holdovers from the Vega line, which ended production after the 1977 model year. Chevy grafted a new Monza front end onto the previous Vega hatchback and wagon body-styles. The Monza 'S', marketed as the Monza price leader, used the Vega hatchback body. The Monza wagon, was also offered in an Estate wood-trimmed version, used the Vega wagon body. The 1978 Monza line gained a new base coupe and 2+2 hatchback with round headlights in an upright front end with a crossbar grille. The Sport 2+2 hatchback and Sport notchback used a modified version of the previous quad rectangular headlamps, now above a full-width open-slot grill. The 151 CID (2.5 liter) inline-4 'Iron Duke' was standard for 1978, replacing the Vega inline-4 engine. Engine options were a Chevrolet-designed 3.2 liter (196 cid) V-6 engine with a 2-barrel carburetor that produced 90-hp at 3600 rpm. Replacing the 3.2 liter V-6 in California and high-altitude areas was Buick's 3.8 liter (231 cid) 105-hp V-6 engine. Four-cylinder engines and the 3.2 liter V-6 were not available in high-altitude areas. The 145-horsepower 305-cubic-inch V-8 remained optional in all but the "S" hatchback and wagon models. Discontinued at the end of the 1978 model year were the 'S' hatchback, Towne Coupe Sport option and the Estate version of the wagon.
The 1979 Chevrolet Monza linup was trimmed to four models. Standard equipment was added for 1979 including an AM radio, tinted glass, bodyside moldings, and sport steering wheel. Only one Monza model kept the sloped Euro-look front end, the 2+2 Sport hatchback. Others had a freshened grille. A more-potent standard 151-cubic-inch (2.5-liter) four-cylinder with a redesigned cross-flow cylinder head and two-barrel carburetor developed 90-horsepower - five more than in 1978. Three optional engines were available: the 105-horsepower 196-cubic-inch V-6, 115-horsepower 231 V-6, or 130-horsepower 305 V-8. The Spyder performance package cost $164, the Spyder appearance package added $231. All Monzas had a color-keyed instrument panel, and all except the base coupe had a center console, and corrosion protection was improved. Discontinued at the end of the 1979 model year were the Monza wagon, the 196 CID (3.2 liter) V6 and the 305 CID (5.0 liter) V8.
The 1980 model year lineup consisted of a base 2+2 hatchback and notchback and 2+2 Sport hatchback; the 151-cubic-inch (2.5-liter) four-cylinder engine remained standard; the only engine option was the 3.8 liter (231 cid) Buick V6. Chevrolet decided to shelve the H-Body and let base models of the Chevrolet Camaro and the new Chevrolet Citation X-11 hold the division's place in the sporty-coupe market.
The Spyder nameplate was originally used to designate the 1962-1964 Corvair turbocharged model. The 'Spyder' name was introduced for the Chevrolet Monza in 1976. This package included performance equipment and some small appearance items. The Monza Spyder Equipment package was available on all 2+2 Hatchbacks and Monza Towne Coupes (with 'Sport Equipment' package) with 5-speed manual and Turbo Hydra-matic automatic transmissions. The Spyder Equipment package included 2-barrel, Dura-Built 2.3 litre engine, floor console unit, large front/rear stabilizer bars, special shock absorbers, steel-belted radial ply blackwall tires, wheel opening mouldings , Day-Night inside mirror, Sport Steering Wheel, Special instrumentation and 'stitched' instrument panel pad with added wood-grain vinyl accents (standard on 2+2), Distinctive "Spyder" identification (script fender emblems, steering wheel horn button insert and Spyder front facia and rear-lock cover)
Chevrolet made extensive changes to the Spyder package including separate Equipment and Appearance packages with separate RPO codes found on the build sheet. The Spyder Equipment Package was regular production option (RPO) Z01, while the Spyder Appearance Package was RPO Z02. The Spyder packages were available on Monza 2+2 Sport Hatchback. Spyder decal colors were determined by the body color of the Monza ordered. There were 4 color combinations for 1977. For 79, there were 6 combos, which included a green and a blue color scheme.
Z01 - Spyder Equipment
-- BR70-13C Steel-belted radial ply blackwall tires, Sport suspension, Sport Steering Wheel (2-spoke wheel), Center Console, Inside day/night rearview mirror, Spyder identification, Wheel opening moldings (available if the Z02 - Spyder Appearance Package was not ordered), Dual tailpipe system and white lettered tires were available in 1979.
Z02 - Spyder Appearance -- Black highlights on front, side and rear of body headlight openings, parking light openings, windshield, rear window and side window moldings, body sill, door and center pillar louvers, rear end panel - (bright window moldings with black exterior), Black or gold rear accents (taillight blackouts and rear end panel decals), Body color front air dam and rear spoiler, Spyder emblems (front facia, rear lock cover and sport steering wheel horn button insert), Body side stripes with Spyder lettering in red, white or gold depending on body color, Black painted styled-steel wheels with trim rings and center caps, Black sport mirrors, Special hood decal and rear spoiler decal.
For the 1980 model year, Chevrolet combined the Spyder Equipment and Appearance packages into one Spyder Equipment package with an RPO code of Z29 and included newly re-designed bold Spyder side decals and a new front air dam that blends into the front fender wheel openings. Spyder decal color choices (five) were based primarily upon the interior color specified rather than the body color as in previous years.
Z29 - Spyder Equipment Package -- BR70-13C steel-belted radial ply blackwall tires (with option for raised white lettering), Sport suspension, Black front and rear bumper rub strips, Black headlights frames, Black windshield, belt, side and rear window moldings (not available with black exterior), Black painted body sill (also not available with black exterior), Black door and center pillar louvers, Black painted taillight frames, Body color front air dam and rear spoiler, Spyder emblems on front facia, rear lock cover and sport steering wheel (horn button insert), Black sport mirrors (LH remote, RH manual), Rear Spoiler and body stripes with Spyder lettering outlined in accent body colour, Spyder hood decal, Black painted Rally II wheels with bright trim rings and center caps.
Car and Driver September 1974, "Preview: Chevrolet Monza 2+2"—Chevy stylists have now proven that Detroit can face off against the best auto artists that Europe has to offer—the Bertones, the Pininfarinas, the Giugiaros—and blast them all out of the ring with a single beautifully executed punch—"We have spread before us on these pages the Monza 2+2, a Vega-based sport coupe from Chevrolet. Take a close look. The designers were thinking of aerodynamics rather than opera windows, of a car that would silently and efficiently pierce the air at freeway speeds. The result is stunning." "At long last, small cars are the prime area of innovation in Detroit." "The origins of this Monza 2+2 are humble enough. It's a Vega by design and dimension, yet almost all of the parts are different. The exterior skin is completely new, as is the floor plan. The rear axle is new, the rear suspension is substantially different and the front suspension maintains the old (and good) geometry with all new parts. So the Monza's resemblance to a Vega is remote." "Two engines will be available at the start of production. Considering its base, it seems quite reasonable that the Vega's optional 2-bbl, 4-cylinder engine should be standard equipment on the Monza. And a new 262-cubic inch version of the small-block V-8 is optional. The real temptation around Chevrolet Engineering is to plug in the 350 4-bbl engine." "There will be a Z/28 Monza just as sure as God made little green traffic lights." "Things are looking up: A real performance motor will fit right in; they've got the sweetest looking car in the land." "Unfortunately, even though the Monza is a bright new car, its gestation period was exactly that time span that the engineers are now trying to forget. The car is compromised, in some places seriously, and it shows. Partly because Ford slid the compact Mustang II on to the market at the best possible time—Chevrolet had to develop a counter move but fast. But even more importantly, the Monza was originally scheduled to debut in mid-1974 as a showcase for the GM rotary engine. The car business was altogether different a few years ago when that plan took shape." The basic Vega was restyled and modified to accept the 206-cu.in. rotary. The most conspicuous change was the high driveline tunnel—necessary because the Wankel's output shaft emerges from the center of its beer-keg shape rather than low down like the crank of a piston engine. How was this new engine for fuel economy? GM had to admit that it was sub-standard and postponed production in favor of further development. But the Monza, hurried along from the beginning was virtually completed. The Monza was too good and too timely—considering the Mustang II's acceptance—to be held off for long. Plan B went into effect: an optional small-block V-8 insted of a rotary for the start of the 1975 model year. The Monza will have special "C Load Range tires which can be inflated to higher pressures and therefore carry more load than the usual BR78. But they are still inadequate for quick, precise steering and agile handling. The Vega (a far lighter car on BR70 radials) is substantially better. When pressed hard through corners it does understeer more than the Vega (an extremely good car by any standards) but substantially less than a Mustang II (also new for 1975) have roughly equal cornering capability, but the Monza is more manageable and more satisfying to drive."
Car and Driver February 1975, "Chevrolet Monza 2+2 vs. Ford Mustang II" — 1975's skinny little new kid on the block takes on Ford's hot-selling bully—and comes out on top.- Patrick Bedard said, "The Mustang II and the Monza are exactly the sort of sporting automobiles that we have been waiting for." "Both were ordered with V-8 engines, power steering and brakes, limited-slip differentials, the best suspensions for handling and the largest available tires. Very likely, the serious driver would order his Monza with a four-speed transmission, but since the V-8 Mustang is automatic only, the Monza was dialed up that way too. And while the Monza is built with a 2.56 axle ratio as standard equipment, we specified the optional 2.93 to match against the Mustang's standard 3.00 gear. So there is no room for excuses. These two cars are as equal as the United Auto Workers can make them. It's Ford against Chevrolet, showdown time. "Both of the coupes borrow heavily from the subcompact sedans in their families." While the Mustang II is an unmistakably quieter and more poised automobile than the Pinto, there remains a certain similarity in ride and handling between the two. In the same fashion, a good bit of the Vega shows up in the Monza. The body structure below the beltline is so similar that both end up with exactly the same overall width. Both also share the same front suspension and steering geometry, although the pieces have been redesigned for the Monza. The brakes, however, are identical. Yet when you drive the Monza, you find that its Vega heritage has been completely camouflaged. The suspension doesn't bottom out, the rear axle doesn't hop over chatter-bumps and the Vega's pitching tendency is completely gone. While it may be technically accurate to consider the Monza a better Vega, that grossly understates the improvement. The Monza's exceptionally supple and well-controlled suspension and the fast power steering combine to make it feel smaller and more agile than the Mustang. Which is, for the most part, an illusion. Of the two, the Monza's interior is definitely preferable. The 262-cubic inch V-8 in the Monza is the latest descendent of the original small-block design and therefore a blood relative of all the high-revving Corvette engines of days gone by. But its two-barrel carburetor as well as its ports and valves have been sized down along with its displacement. It ends up being smooth, sweet and slow: 18.5 seconds in the quarter with a speed of 75.4 mph. The Mustang is plenty nose-heavy (58.2 percent of the total), but the suspension copes with it adequately. By contrast, the Monza carries 55.9 percent of its weight on the front wheels and does so quite happily. Of the two, the Monza is clearly the most enjoyable on a road course. The steering (at 2.8 turns lock-to-lock) is exceptionally quick, and the rear axle is marvelously well controlled, 10 times better than the Vega and probably the best of any U.S.-built car. Credit the torque-arm rear suspension for this breakthrough. Add the fact that the front suspension is far less likely than the Vega's to bottom abruptly on the bumps and you have a car free of evil spirits. But you feel the weight. Even with the quick steering you can't point the Monza into a turn with the sharp precision that you can a Vega, but you can easily dial in the corrections necessary to keep up with the flabby tires and moderate understeer. But there is an important difference in fuel economy—the Monza having an advantage here. And the Chevrolet offers substantially more driving pleasure. The controls are more alive and accurate, the driving position is far more comfortable and the styling is crisp and agreeable. From the driver's seat, you have the impression of a modern car. The roof pillars are thin for broad visibility and the hood slopes down for a close-up view of the road. By contrast, the Mustang is old-style Ford—a high, flat hoodline with the sunlight blocked out of the interior by wide pillars. Taken altogether, the Monza is simply more fun to drive. Which is what you buy this sort of car for."
Chevrolet Monzas participated in the IMSA GT Series powered by Chevrolet Corvette engines. Chevrolet Monzas were the challengers in the new AAGT class. The class was designed to allow such cars to compete with the best GT cars in the world. The 1975 season was launched with the new cars that would compete with the dominating Porsche Carreras. A very liberal set of rules allowed some body panels to be retained - the windshield, the rear window and the roof. Everything else was built from scratch.
Al Holbert saw the Monza's potential. By the end of the 1975 season, he had ordered a brand new car, prepared by Dekon Engineering built by Lee Dykstra. Chassis #1008 would be used starting for the 1976 season. In 1976 and 1977, he was the IMSA Camel GT Champion, beating Hans Stuck to Brian Redman to Peter Gregg. In Al Holbert successful 1977 campaign he captured another Camel GT crown. Unfortunately, it would be the last title for an American car. The Porsche 935s were becoming unbeatable right from the beginning of the 1978 season. However, the Dekon built Chevrolet Monza left its footprint on the IMSA Camel GT. They were quite unbeatable in 1976-1977. Chevrolet Monzas were to be seen in IMSA until 1986.