Dodge Viper Head and Cam Setup Guide: Prefix, JM Striker, and How to Pair Them Right
Dodge Viper Head and Cam: What Actually Moves the Needle on the V10
On a naturally aspirated Viper, the biggest gains available without touching the bottom end come from heads and cam. A well-matched head-and-cam package on a Gen III, for instance, can push 620 to 640 rwhp on a stock short block. The hardware to get there exists across a handful of builders. The difficulty is pairing the right cam profile to the head you chose — and understanding that these are not interchangeable decisions.
JM Cylinder Heads and the Striker Line
JM Cylinder Heads produced what the Viper community still treats as the reference point for N/A port work on the V10. The builder behind the Striker heads brought formal CFD experience to the job — not just flow bench numbers, but attention to port velocity and swirl, the factors that turn peak flow figures into usable torque. That shows when you compare the port geometry to what the stock casting looks like out of the box.
The Striker line came in Stage 1, 2, and 3, each designating a deeper level of porting from the stock casting. Stage 1 is a cleanup pass; Stage 3 is as far as the factory casting can be taken. Documented gains with a matched cam run 100 to 135 hp, and the heads were made compatible across Gen 1, Gen 2, and Gen 3 applications.
Production has ended. The remaining inventory lives at Southeast Performance R/T, and once that stock is gone it is gone. If a set comes up and the application fits, there is no waiting-for-a-better-deal play here.
Prefix Corporation: Cams and Complete Packages
Prefix takes a broader approach — they offer the camshaft, the supporting hardware, and full engine packages rather than standalone head work.
Their Gen 1/2 performance camshaft runs .566″/.571″ lift with 227/233 duration at .050″ on a 113-degree centerline. The Gen 3 camshaft steps up to .601″/.606″ lift at the same 227/233 duration. Neither is a mild grind, and both are designed to work with heads that have been opened up. Valve spring upgrades are required for either fitment — this is not optional hardware.
At the extreme end, Prefix built a 9.0-liter stroker package for the Gen 5 Viper with CNC cylinder heads, 2.125-inch intake valves, 1.608-inch exhaust valves, and a purpose-ground non-VVT camshaft, producing figures in the 825 hp range. That gives a sense of how far the Prefix ecosystem scales when the budget is open.
Greg Good: The Third Name You Will Encounter
Greg Good comes up in almost every Gen III N/A discussion. His head-and-cam combination on stock-displacement Gen III cars consistently puts down 625 to 630 rwhp, with documented builds hitting 643 rwhp when paired with a cold-air intake and a sharp tune from A&C Performance. His cam profile runs around 236/242 at .050″ with .615″/.621″ lift on a 112-degree lobe separation angle. That profile tells you something about where the engine wants to live — comfortable at 112 LSA, high lift, meaningful duration spread between intake and exhaust.
Matching the Cam to the Heads
This is where builds come apart. People source excellent heads and then run a cam that was not dialed for that port volume and velocity target.
Larger ports need more cam duration to maintain velocity at lower rpm. Without it, a big-port head will feel hollow below 4,000 rpm even if the peak numbers look great. Most street builds stay in the 112 to 114-degree LSA range for drivability. Going wider (115+) spreads the powerband but thins it — fine for a dedicated track car, not ideal for something that also drives to work.
Lift matters, but duration at .050″ matters as much for where the power arrives. A high-lift, short-duration cam on an aggressively ported head produces a strong peak but a narrow band. For a car that sees occasional track days, that trade is usually a mistake.
Valve Springs: Part of the Cam Cost
Every performance cam profile listed here exceeds stock Viper spring-seat pressure specifications. Run stock springs with any of these profiles and you will float valves at high rpm. Spring failure follows. New springs are not an upgrade — they are a requirement that belongs in the initial budget.
Match to the cam manufacturer’s spec sheet rather than to a generic lift number. Installed height, bind clearance, and coil bind clearance all need to be verified against the specific spring and retainer combination you are running.
The Tune Is Not Optional Either
None of the power numbers above happen on a stock calibration. A&C Performance is the shop referenced most consistently in the community for N/A Viper tuning, specifically because of their depth with Viper-specific calibration rather than a generic V10 map. The hardware creates potential. The tune is what turns that potential into consistent, repeatable power across the operating range — not just a peak number on a single dyno pull.