Gadgetory

I'm Brian Cooley from CNET on cars taking another of your emails about high-tech cars and modern driving and this one comes in from William V who asks could we explain the technology behind a CVT continuously variable transmissions and why they're not used for more performance cars he says one would think the ability of a CVT to maintain an ideal engine power band at all times would make it a perfect gearbox for sports performance and racing equipment it absolutely would seem that way William and I'm with you on that being able to keep an engine in that rpm sweet spot is one of the Holy Grails of performance but there's a problem CVT is don't have really strong positive engagement because they are not made up of cogs and teeth the way a traditional transmission is or really hard locking clutches and torque converters they're kind of a constant slipping mechanism as a result they don't handle really high power all that well that's not where they have found their main role though they do maintain the sweet spot in engines but mostly to seek economy not to seek maximum power and torque output a CVT as you probably know is made up of a bunch of pulleys and belts a variable pulley metal steel belt that is able to slide between these varying pulley flanges all the time that's the nature of it's slightly slippery technology we did a whole episode on transmissions back in May of 2013 it was episode 18 that explains this really well I'll put a link in the show notes you have to go hunting for it the show notes for this episode over at C net on cars.com another issue around CBTs in performance cars is that they don't sound the same a car with a CVT tends to constantly be in about the same rev range more or less it doesn't run all the way down and all the way up the way a geared transmission can or could and therefore it's not going to be very satisfying in the performance driver who likes the sound of running through the gears and a real transmission you