Interesting Thread--- so I run a PROCHARGER F1R on my '99 GTS; works excellent although it whistles(like that!!) Performance is really great! You can buy complete set up for your viper from JMB PERFORMANCE. They are located in Hillsboro, MO. 63050. (314) 540-1541. cost is $7600- $8600. I also use a SNOW PERFORMANCE METH INJECTION system, I mix my own juice-- 50% methanol 55 and 50% -20* windshield washer fluid. Been running the set up for years, very happy with performance!!