Max HP Cams, Boosted / Nitrous / Naturally Aspirated Hydraulic Roller Cams

Max HP Naturally Aspirated (N/A) Focus

For the N/A builder seeking the absolute highest power figures possible from a pump gas street/strip setup, the Max HP N/A Hydraulic Roller Cams are a necessity. These cams utilize aggressive duration and lift profiles to maximize the flow potential of heavily ported cylinder heads (like the 340+ CFM heads used in Butler's 700hp combos).

The focus here is on extending the effective power band well past $6,000$ RPM and ensuring the valves are held open long enough to completely fill the massive cylinders (typically 461ci to 535ci).

• Example Grind (Stage 2 N/A Cam): Often featuring high duration figures (e.g., 243\249 duration at .050 inch lift) and substantial lobe lifts (around .399 inch), these cams utilize a relatively wider 112 or 114 Lobe Separation Angle (LSA) to balance peak power potential with slightly improved manners and a wider power band.

   

• Application: Ideal for large displacement engines utilizing high-compression, fully ported heads, and single-plane intake manifolds.

Power Adder Cams: Optimized for Boost and Nitrous

Building an engine for Boost (Supercharger/Turbocharger) or Nitrous Oxide injection requires a completely different cam profile than a naturally aspirated engine. These power adders drastically change the engine's volumetric efficiency and stress, demanding specialized camshaft timing.

Butler Performance's Max HP Power Adder Cams are custom-tailored to handle the unique air-flow requirements of forced induction and chemical supercharging:

1. Nitrous Cams: Nitrous oxide (N2O) is an internal supercharger. Cams for N2O typically have split duration—where the exhaust duration is significantly longer than the intake duration—to efficiently evacuate the massive amount of exhaust gas produced by the powerful combustion event.

2. Boost Cams (Turbo/Supercharger): Forced induction applications often require wider Lobe Separation Angles (LSA), typically 114 to 115, and less overlap between the intake and exhaust valves. This is critical to prevent the pressurized air/fuel mixture from exiting prematurely ("reversion") through the open exhaust valve when both valves are open—a phenomenon caused by high exhaust backpressure common with turbochargers.

• Example Boost Cam (Stage 1 Turbo/Pro-Charger): These grinds often feature conservative duration at .050 inch lift (e.g., 236/244) paired with a wider 114 LSA. The emphasis shifts from maximizing raw duration to correctly managing airflow and pressure across the valve events.

    

The Complete Max HP Valvetrain

 Due to the extreme stresses and RPM targets of these Max HP profiles, the entire valvetrain must be upgraded to race-level components:

• Billet Core: The camshaft itself is ground on a premium billet steel core for maximum strength.

• High-End Lifters: Premium, reduced-travel hydraulic roller lifters (such as Johnson or Morel) are required to maintain valve control at high RPMs and high boost pressures, preventing the lifter from "pumping up" and floating the valves.

• Springs and Pushrods: The valve spring package must have the necessary pressure and travel to control the high lift (often over .600 inch with 1.65 ratio rockers) and rapid valve acceleration. Heavy-duty, thick-wall pushrods are non-negotiable to prevent flex.

• Clearance: Builders must be vigilant about checking piston-to-valve clearance, which becomes extremely tight with high lift and long duration, especially in stroker motors.

The Butler Performance Max HP Hydraulic Roller Cams are essential components for any Pontiac engine destined for serious competition or the highest echelon of street power, offering a proven pathway to extreme horsepower through precise, application-specific engineering.