and , while the 96–97 cars were rated at and . The 96–97 WS6 and SS F-bodies were rated at . The 94–96 B- and D-body version was rated at and ( with V08 mechanical fan as part of V92 or V4P towing option groups). LT4 The LT4 was the special high-performance version of the new-generation LT1. It featured a slightly more aggressive camshaft profile, 1.6:1 aluminum roller rocker arms, lighter hollow intake valves and liquid-sodium filled exhaust valves, larger fuel injectors, performance crankshaft, higher 10.8:1 compression ratio and high-flow intake manifold (painted red) with extra material above the port available to allow port matching to the raised port LT4 cylinder heads. The LT4 was conservatively underrated at and . It was introduced in the 1996 model year, for the last year of the C4 Corvette, and came standard on all manual transmission (ZF 6-speed equipped) C4 Corvettes. The engine was passed down to 1997 SLP Camaros SS and SLP Firehawks with 6-speed manual transmissions. The LT4 was available on the following vehicles: 1996 Chevrolet Corvette only when equipped with 6-speed manual transmission (includes all Grand Sports) (Production: 6,359) 1997 Chevrolet Camaro SLP/LT4 SS 6-speed (Production: 100 for the U.S., 6 for Canada. There were 2 prototypes) 1997 Pontiac Firebird SLP/LT4 Firehawk 6-speed (Production: 29) All 135 production engines for the Firehawks and SSs were completely disassembled, balanced, blueprinted and honed with stress plates. One in 5 engines was tested on a Superflow engine dyno. Every car was tested on a chassis dyno and then performed a road test. 3.90 in bore blocks 5.7 L LT5 For model year 1990, Chevrolet released the Corvette ZR-1 with the radical Lotus Engineering-designed double overhead cam LT5 engine. Engineered in the UK but produced and assembled in Stillwater, Oklahoma by specialty engine builder Mercury Marine, the all-aluminum LT5 shared only the 4.4 inch bore spacing with any previous sbc engine. It does not have reverse cooling and is generally not considered a small block Chevrolet. Used only in Corvettes, the LT5 was the work of a team headed by Design manager David Whitehead, and was hand built by one headed by project engineer Terry D. Stinson. It displaced and had a bore x stroke instead of the usual and featured Lotus-designed DOHC 4 valves per cylinder rather than the usual Chevrolet 16-Valve OHV Heads. The preproduction LT5 initially produced , but was reduced