This Estoril Blue Roadster BMW Z3 is the ultimate performance version of that car, an BMW/Dinan ISR-3 Roadster. Less than 100 BMW Dinan ISR-3 were ever produced. I am told that the actual number was 46. ISR-3 roadster stands for Intercooled Supercharged Roadster. Each ISR-3 made is unique, they are numbered. Each has a prominent number plate under the hood. And this one bears the number “07”.
The ISR-3 Package, which stands for Intercooled, Supercharged Roadster, adds virtually every high-performance upgrade that Dinan offered for the E36/7 M Roadster. The S52 3.2L inline-six engine now features a Dinan/Vortech belt-driven supercharger that delivers 10lbs of boost, with a Dinan air-to-air intercooler to prevent heat soak. To best utilize the added power from the supercharger, the engine also features Dinan performance software, high-flow intake, high-flow throttle bodies, high-flow fuel injectors and a low-pressure Dinan Free Flow exhaust system. The 5-speed manual transmission is also upgraded with a lightweight clutch and the OEM rear end has been replaced by a 3.38 limited slip differential. The car rolls on lightweight 18″ Dinan wheels and the suspension has been improved with an aluminum & carbon fiber strut tower brace, Koni dampers, performance springs and larger sway bars. All said and done, this M Roadster pumps out incredible horse power and torque in a 3, 100lb package that will rocket to 60mphin the low 4s and pulls .91gs on the skid pad and touch a top speed near 160mph.
Factory features of this M Roadster include a premium Harman/Kardon audio system, heated sport seats, optional AM/FM radio with CD player, a sport steering wheel, power-operated soft top, roll bars and air conditioning.