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.
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".
In 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.
BOCA BROTHERS PARTICIPATE IN THE AMAZON INFLUENCER PROGRAM.
5 окт 2024
