The HTT Pléthore is a Canadian concept car, developed and produced by HTT Automobile in Quebec.

It debuted at the 2007 Montreal International Auto Show as a pre-production prototype under the name "Locus Pléthore", under the supervision of Luc Chartrand.^[1] It has a supercharged 6.2L V8 LS9 with 750 hp (559 kW) and 655 lb⋅ft (888 N⋅m) of torque or an optional high performance homemade V8 engine with 1,100 hp (820 kW). This engine is supported by Pratt & Miller^[2] and based on the supercharged V8 from the Corvette ZR1.^[3] The chassis and body are made entirely out of carbon fibre with no engine subframe, resulting in the chassis being exceptionally rigid.^[4] The car will weigh approximately 1,089 kg (2,401 lb) and, if mated to the 1,100 hp (820 kW) engine, will have a power-to-weight ratio equivalent to that of a Formula One race car. Two prototypes were constructed, the second suggests a center seating position previously featured in the McLaren F1, 1966 Ferrari 365 P prototype, and the 1969 Bizzarrini Manta Concept.^[4][5] HTT Automobile planned to custom build a limited lifetime production run of 99 Pléthores.^[6]