The 633CSi replaced the 630 late in the 1978 model year. It too was a 2+2 GT-style coupe. The weight stayed the same at around 3400 lbs., and it shared the same wheelbase of 103.4 inches. Base price was $24780.
The big difference was the engine. This one had a 3.2L SOHC EFI I6. It didn’t make much more ‘get up and go’ than the 3.0 liter it replaced. The U.S.-spec 3.2 liter made 177hp and 196tq. The same 4-speed Getrag manual and 3-speed automatic were the transmissions that could be had.
Power steering and air conditioning were standard features. For options, besides the automatic transmission, were sunroof, leather interior and BBS alloy wheels.
In 1980, the 3.2 engine lost a few horsepower down to 174. A 5-speed manual trans replaced the standard 4-speed though. For 1983, the horsepower rating crept back up to 181. By this time, base price was now $39120.