I know you can buy different synchros, don't know if they make a kit. They do have cabon lined ones over the brass. There are a few others but brass seems to handle the most TQ. Take into account the aftermarket may give a better shift but they have pros and cons. Like during the burnouts don't seem to agree with them. Contact a reputable shop and get their opinion. You can always contact Tremec. For some odd reason they give you great info on what should be in the transmission lol