I changed the rear end of my 74 Jav from a 2.87 to a 3.54 and my speedo is now showing much faster than actual. I believe I remember a site being mentioned that had the formula for calculating speed from tach reading based on various parameters. Anyone have the site bookmarked? Thanks. Marty Is there a way to determine what speedometer gear I need to order for my 998 tranny (I assume the MOPAR guys would not be much help on figuring it out but they probably carry the gear) __________________________________ Start your day with Yahoo! - Make it your home page! http://www.yahoo.com/r/hs