Jerry Danner’s C900 Gear Ratio to Road Speed Calculation Spreadsheet February 2, 2025 February 2, 2025 DIYDS calculator, differential, do it your damn self, gear, mph, ratio, rpm, saab No Comments On January 30th, Jerry Danner (famously of Mile High Automotive) created a post on FaceBook that began… How fast are you traveling at a given RPM on your 1991 C900T… Read More