The first version of the 1.5 appeared in the Fit in 2014 and achieved crazy MPG https://www.motor1.com/news/40082/2014-honda-fit-jazz-goes-official/
That was an interesting read - 85mpg estimated in the Fit. Did Honda ever mass produce the Fit in that configuration, maybe elsewhere in the world? -Skip
I wish that Fit had been more available! However, it's not the Clarity powertrain, because that Fit has a 7 speed dual clutch transmission and a different electric motor. Not sure about the gas engine either; Honda may have developed a new or modified version of the 1.5L for the Clarity?
I upgraded from a 2015 Fit and after 53K miles including 4 round trips from TX to FL, I averaged a combined 43mpg. The Clarity when it revs sounds like my Fit on the highway so I'm used to the engine noise. The Fit is a great commuter car but there were compromises to achieve the fuel efficiency such as smaller, cramped cabin, less sound deadening materials and no power seats at the top of the line model. Survived a 70mph crash in the Fit and walked away with mild bruising. Real pleased with the emphasis on safety that Honda puts in all of its cars.
The Clarity uses the LEB3 1.5l DOHC i-VTEC Atkinson-cycle version of Honda's L series engine. 1.5-liter, DOHC, i-VTEC® Atkinson-cycle inline-4 cylinder engine Engine output: 103 peak horsepower (SAE net) at 5,500 rpm Engine output: 99 lb.-ft. peak torque (SAE net) at 5,000 rpm i-VTEC® (Variable Valve Timing and Lift Electronic Control) + Electric VTC Computer-controlled port fuel injection with multi-hole fuel injectors 13.5:1 compression ratio The closest engine I could find is the 1.5l DOHC i-VTEC L15B1 from the 2015+ Fit. https://en.wikipedia.org/wiki/Honda_L_engine http://asia.vtec.net/Series/FitJazz/lseries/index.html