After a three-year sales decline, the Vega and its aluminium engine were discontinued at the end of the 1977 model year. Pontiac's lowest-priced car was a re-badged Vega variant exclusively available in Canada for the 1973-74 model years, and introduced in the U.S. the following year. The final 1977 models featured the first use of Pontiac's Iron Duke inline-4 engine. Lower priced versions of the Chevrolet Monza were introduced for 1978 and rebadged variants of the discontinued Vega were also added to the Monza line - the Monza wagon using the Vega Kammback body was sold for the 1978-79 model years, and the Monza S hatchback, a price leader model using the Vega Hatchback body, was also offered for the 1978 model year. The Ford Pinto was introduced one day after the Vega. It was small, economical, and a top seller. However, it had a key safety design fault - the position of the fuel tank meant that it would be crushed in a rear-end collision, creating a major fire risk. Ford Company memos presented as evidence during the civil trials revealed that these remedies were discussed, with the conclusion that to shut down production and retool would be too expensive. Official memos published in "Mother Jones" detailed a cost analysis of corporate liability in the event of having to compensate crash victims. The "Ford Pinto memo" ruthlessly calculated the cost of reinforcing the rear end ($121 million) versus the potential payout to victims (). The Ford Pinto engine though was successful in European Fords for twenty years, in successive mid and large European sized mainstay models of the; UK Ford Cortina, German Ford Taunus, the Ford Sierra, and the Ford Granada amongst others. By 1970, Nissan released their first front-wheel-drive car that was originally developed by Prince Motor Company which had merged with Nissan in 1966. This was introduced in 1970 as the Datsun/Nissan Cherry. In 1973, the Energy Crisis started, which made small fuel efficient cars more desirable, and the North American driver began exchanging their large cars for the smaller, imported compacts that cost less to fill up and were inexpensive to maintain. The Toyota Corona, the Datsun 510, the Mitsubishi Galant (a captive import from Chrysler sold as the Dodge Colt), the Subaru DL, and later the Honda Accord gave buyers increased passenger space and some luxury amenities, such as air conditioning, power steering, AM-FM radios, and even power windows and central locking without increasing the price of the vehicle.