The 306 - Winterized. After a few trips up to Snowin' Sound where I go to school, it was evident that the carburetor wasn't fond of winter either. I'd get going 5 or 6 miles down the road, and found I could let off the throttle and I had cruise control - the throttle plates were freezing. Along with that, the choke would freeze shut and run like a bag of poop. So I cleaned up the original air cleaner and stuck it on, along with a heat riser from the header.