1988 928 S4 5-Speed

The 928 S4 arrived in 1987 as a thoroughly updated version of the grand tourer, bringing both more power and sleeker styling. Its 5.0-liter V8 received significant revisions, including new cylinder heads with larger valves, altered valve timing, and a two-stage intake manifold, boosting output to 320 hp. Visually, the S4 stood apart with a smoother, more aerodynamic design featuring a “detached” rear wing, flush-mounted tail lamps, deeper rocker panels, and a bonded-in windshield, all of which contributed to a reduced drag coefficient of just 0.34. The updates combined to make the S4 both faster and more refined, marking an important evolution in the 928’s lineage.

This 1988 928 S4 5-Speed is a one-owner car, originally purchased through Porsche’s Tourist Delivery Program and finished in Venetian Blue Metallic over a Cobalt Blue leather interior. Now showing 213k miles, it is accompanied by service records in the gallery with most recent work in May 2025 including having the cylinder heads were rebuilt and both the timing belt and water pump were replaced, providing confidence in its mechanical condition. A high-mileage example, but one with long-term ownership and recent major service make it a compelling driver example.

Over the past twelve months, 928 S4s have averaged $49,200 with results ranging from $18,000 to $166,993. High-mileage examples generally trade in the $15,000–$35,000 range, and this Venetian Blue one-owner car fell right toward the bottom of that band, selling at a final bid of $17,100. Given its long-term ownership and service history, this looked like a very nice example for the money. Well bought.

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