Jeff you are spot on for your treatment of motors. Prolong was used in the past but now Tribo is a little more popular and shows a touch better on the dyno.

Eagle or Tobee makes the other gearset and it is not legal for TCS. We have used it in an Enduro car to get the FDR down to a 5.2 and the Sedans we were racing in an Enduro with could not believe the speed. We also had Sedan rims on an M04M Miata.