Absolutely.
My Ford Aspire has 165/80/13" wheels and I recently put 195/55/15" on the car and there was a _noticeable_ increase in drag. I have a 1.1 stretch of road that I coast down and I wasn't able to make it all the way with the wider tires.
I took them off, and now I'm back to the 165/83-13", and she coasts as smooth as ever.
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