My Opinion of Modifications, But first join the VCA.
1.0 Learn Performance Driving
1.1 Take the 2 Day Skip Barber Driving School, discounted 20% to VCA members.
1.2 Take a few Car Control Clinics, 10% discount
1.3 Take the 3 Day Racing School, 10% discount
1.4 Continue with Lapping days to stay sharp
1.5 Autocross as much as convenient to in condition of Car Control
(these modifications will provide more performance improvement then engine work)
2. K&N air filters are the best $/HP gain. If you want a louder sound get a Cat-Back, want it louder and more HP, get headers and high flow cats. Want to spend more $$ there are lost of places to spend $$ on a Viper.
The best modification is the Driving School. I have spent a few $$ and the car is loud. A good driver in a 100% stock Viper will have better times during a Viper Days driving school.
Welcome to the world of Viperholics!