here ya go ...hope this helps ...
Tuning the 2004 Viper with pipes requires some extra attention to avoid triggering the deto sensor light.
While pipes on the 2004 perform within the same specifications as the 2002 and 2003 Vipers, the addition of the detonation sensor to the 2004 models has caused problems for some triple piped Viper owners. The deto sensor is very sensitive, and is often triggered when running pipes with the stock compression, which is not the same for all three cylinders. Our Viper Head mod is a recommended modification for all triple pipe owners. The unequal compression in the Viper cylinder head is designed to correct a stock y-pipe- caused temperature variation in the cylinders. Since triple pipes eliminate the y-pipe, a return to the more desirable equal compression is possible for triple pipes Vipers. This is most beneficial, and mandatory for operation of VIper triple pipes on deto-sensor equipped models. Click here VIPM02 to order the mod. You'll send in your own stock head for trade or modification