here in the southeat us rx-7 guys share info about what we've learn to make our cars faster ....even helpin each other at the track ! you will need to keep the front muffler fresh.(about 4/8 hp off when it burns out) i'm going to change to a repackable bullet type muffler next. i think this will be the trick ! lets keep these "old" cars out front !! hope this helps .. racing ralph