Yes. I took mine to a shop that did a good job on another friends car. for some reason they didnt think that they would have to time the car after they installed my Underdrives basicly they slapped the pulleys on then cranked it up. A few clunks and bangs later and they owed me a new engine. They could have made an extra 100 by sending it to the dealer to time it but instead they got a $4000 bill from mazda for a new engine.
