They are small but mighty. I wish I had a video going this weekend when 3 of us caravanned to the car show. Toby in his late model Hemi Dodge pick up, Mopar Joe with his 475 horse powered 70 Super Bee, and me folling up with my 273-4 barrell 4 speed 66 Dart. We were passing cars on the 2 lane roads and I didn't downshift. Just romp on the gas, kick in the secondaries and blast past the car or truck going 60. There wasn't anything that they did that I couldn't do with my little 273. And I got just a tick less than 18 mpg on the trip home running 60+ on the interstate.