I drove one (rental car) in 1988 for about 6000 km in the US south west. It was a great car, took about 5 l per 100 km. Much better to drive than the cheap Chevy they gave me first and which I gave back to get a car with stick shift.
I have owned a Civic with the odd CVCC (Compound Vortex Controlled Combustion) that they did for enhanced combustion (it worked great & I did not enhance anything on it [it was just a hooptie beater but worked well for my purposes at the time] {never needing to go over 45 MPH in a 20 mile radius}).
And I had a 2007 Honda Fit that I did modify some (Michelin Defender T&H tires 3 sizes wider & a 1/2 aspect ratio taller, KYB Gas-A-Just struts & exhaust & intake mods (which created better torque and fuel economy).
It was a city/rural car and served it's purpose very well, sold it in 2019 with 54K miles on it.
I set up a 1988 Honda CRX SI like the Jackson Racing one for street duty: with the European DBL OVERHEAD CAM cylinder head, a Jackson Racing exhaust system (with a moderate sounding muffler and tuned it to 128 HP (at the front wheels vs. the original 108 rating at the flywheel), put on Jackson Racing Tokiko 5 way adjustable struts, used Jackson Racing anti sway bars, Yokohama 008 tires. and a Quaife limited slip differential and a Jackson Racing supercharger
It would beat a 5.0 Mustang in the first & second gears (of the CRX), then the Mustang could pull away from it.
It could also outrun a Ferrari 328 in an autocross style slalom. You can look it up (the July 1988 issue of
Road & Track Magazine hit the shelves with a Ferrari and a Porsche BEHIND a
Honda. The Jackson Racing CRX Si upset the giants in the test).
And, as expected, the fuel economy remained very close to the same (the old 1988 CRX Si: 27 mpg combined on the post-2008 cycle, the modified on does 26 mpg on that cycle).