The Four Speeds Hunt4cleanair（四个速度Hunt4cleanair）.pdf

The Four Speeds hy this title that sounds like a movie title from the 1970s? The point is to Wunderscore a discreet fact that three four-speeds were used for installa- tion when manual transmission was called out on the dealer order during the 1978 model year. The significance is that for decades, published sources gave the impression that 3,385 four-speeds of two varieties were installed in the 46,776 Corvettes built, and this pushes the myth that only 200 1978 Limited-Edition Pace Cars were equipped with the L82 M21 power team. This belief has caused mis- speculation about the rarity of this option, but with study of original four-speed cars, build sheets and observation, the full story can be told. Figure 1. 1978-79 Muncie cast-iron maincase and extension housing This article describes the three four speeds installed in 1978 Corvettes and reveals the findings of a study of 1978 production and build documents. The discussion will include the use of Regular Production Options (RPOs) and show how some were used on production documents (orders and retail labels) while others were used exclusively on build documents (manifests). Finally, the article will show broadcast codes captured from low-mileage four-speeds cars that reconcile with codes on