Editing Quad 4 engine (section)

===Factory prototypes===
At the same time that Oldsmobile announced the planned high-output "HO" Quad&nbsp;4 in 1988, they suggested that a turbocharged version producing up to {{cvt|250|bhp|kW|0}} was planned. A turbocharged Quad&nbsp;4 with a reported {{cvt|200|hp|0}} was installed in an Oldsmobile 98 that was previewed by [[MotorWeek]]. A turbocharged Quad&nbsp;4 was never released as a production option.<ref name="jalopnik-mar2019"/><ref name="mw-feb2020"/>

The pace car for the 1988 Indianapolis 500 was an Oldsmobile Cutlass Supreme that had been converted into an open car by Cars and Concepts. The engine was a turbocharged 2.3-liter Quad&nbsp;4 built mainly with factory parts that produced {{cvt|250|hp|kW}} at 6400&nbsp;rpm.<ref name="wbody-1988pace"/>

The Oldsmobile Aerotech II and Aerotech III were both released in 1989. The Aerotech II is a wagon-back sports coupe concept with a 2.3-liter Quad&nbsp;4 making {{cvt|230|hp|kW}} with some form of forced induction. The Aerotech III is essentially a preview of the 1990 Oldsmobile Cutlass Supreme sedan, and came with a supercharged 2.3-litre Quad&nbsp;4 that developed {{cvt|230|hp|kW}}.<ref name="oo-concepts"/>