Can someone tell me who built the 90s "F" engines after Toro bought lawn boy? I have a '97 F series that runs really smooth as compared to the Duraforce models I own. I live in Mpls., and have driven by the Toro plant many times, and I don't think they have an engine plant there. I also have a Toro CCR 2450 snow blower with the R-tek 141cc engine. It says Briggs right on it. I must say, it sure sounds a lot like a Duraforce.