first, $60 is amazing for MAC, my only problem w/ them is they are hella overpriced... just make sure no rust, or holes
-chips are just about as good as tweecers, only you can only do one change to them... then you have to re-burn the chip... totally worth the tweecer, unless you don't plan on doing anything else to your car...
-all chips/tweecer should increase the shift curves, although I highly doubt that it will actually shift faster, as they shift about as fast as they can, although it will re-draw the graph, so the computer will shift later when floored, and earler when not... better economy, and better 1/4 times...
-chips are just about as good as tweecers, only you can only do one change to them... then you have to re-burn the chip... totally worth the tweecer, unless you don't plan on doing anything else to your car...
-all chips/tweecer should increase the shift curves, although I highly doubt that it will actually shift faster, as they shift about as fast as they can, although it will re-draw the graph, so the computer will shift later when floored, and earler when not... better economy, and better 1/4 times...