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335 Camshaft - Honda GX390/Big Block Clone
.335 Lift Camshaft - Honda GX390/Big Block Clones
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335 Camshaft - Honda GX390/Big Block Clone

Part Number: 335-GX390
Online Price: $149.99
DynoCams 335 Camshaft for Honda GX390 & Big Block Clone Engines
Availability: In Stock.

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Description

DynoCams 335 Camshaft – Honda GX390 & Big Block Clone Engines


The DynoCams 335 Camshaft is a serious, top-end-focused racing camshaft engineered for Honda GX390 and big block clone engines. With moderate lift positioned between the .308–.315 cams and high-lift .356–.360 profiles, the 335 is designed to deliver maximum RPM horsepower in restricted stock-appearing builds as well as fully modified combinations using billet cylinder heads.


This is an all-out competition camshaft and is not recommended for mild builds or engines operating below 5,000 RPM.


Designed for Ratio Rockers

The DynoCams 335 features a .335” lift profile optimized for use with ratio rocker arms:

  • 1.2 ratio rockers yield just over .400” total valve lift, compatible with most modified cylinder heads.
  • 1.3 ratio rockers increase total lift to approximately .435”, which may require additional cylinder head modifications, increased installed spring height, and higher spring pressure to maintain valvetrain control.


Performance Characteristics

The DynoCams 335 is significantly more aggressive than lower-lift, shorter-duration camshafts. While GX390 big block engines are well known for strong low-speed torque, the longer duration of the 335 trades some low-RPM torque in favor of increased midrange and top-end power.


This camshaft is a popular choice for stock-appearing racing builds, where airflow is restricted by modified stock-based carburetors. The increased duration keeps the valves open longer, helping overcome intake limitations and produce more usable horsepower in the mid and upper RPM ranges.


The 335 can also be used in high-flow combinations with larger carburetors and billet cylinder heads, but in these setups the power band becomes more focused on top-end RPM. In lighter-weight chassis, this characteristic can act as a form of traction control, reducing excessive low-speed torque while delivering strong high-RPM performance.


Idle quality will range from mildly rough in stock-appearing builds to aggressively rough in high-flow combinations, especially when using ratio rockers and billet heads. Higher clutch stall speeds may be required to prevent off-idle hesitation.


Built for Durability

The DynoCams 335 Camshaft features a hard-welded lobe design, providing excellent wear resistance in high-RPM, high-spring-pressure racing environments. Due to its aggressive profile, upgraded dual valve springs are mandatoryfor proper valvetrain control and long-term reliability.


Recommended Supporting Components

To fully unlock the performance potential of the DynoCams 335 Camshaft, the following components are strongly recommended:

  • Stock-Appearing Modified or 34mm+ Carburetor
  • Billet Connecting Rod
  • Billet Flywheel
  • Billet Rocker Arms
  • Chromoly Pushrods
  • Big Valves & Porting
    Larger valves and professional port work raise the effective power band and significantly extend top-end horsepower. Big block engines naturally produce strong low-RPM torque, so increased airflow does not negatively affect bottom-end performance.


Fitment

  • Honda GX390
  • Predator 420 Wedge (Non-Hemi)
  • Wildcat 460
  • Cam Boss Diameter: 16mm (.628")

Important: Camshaft-to-block and camshaft-to-rod clearance must be inspected during installation.


Technical Specifications

Engine Platform: Honda GX390 / Big Block Clone
Recommended Class: Modified
Target Maximum RPM: 7,800 RPM
Valve Spring Pressure (Intake / Exhaust): 50–55 lbs Dual Springs
Valve Lash (Intake / Exhaust): .003"

I

gnition Timing Recommendations

  • Pump Gas: Not Recommended
  • Race Gas (110 Octane): 32° BTDC
  • Methanol: 36° BTDC

Recommended Compression Ratio: 13:1


Camshaft Timing & Lift Specifications

Specification

Intake

Exhaust

Open

55.20° BTDC

96.65° BBDC

Close

95.75° ABDC

60.70° ATDC

Lift

.334"

.334"

Centerline

108.0° ATDC

108.0° BTDC

Duration @ .050"

259.75°

264.70°

Duration @ .200"

172.15°

178.30°


Why Choose the DynoCams 335?

  • Designed for high-RPM racing applications
  • Excellent choice for stock-appearing restricted builds
  • Strong top-end power with controlled low-RPM torque
  • Works with ratio rockers and billet cylinder heads
  • Hard-welded for durability in extreme racing conditions

FAQ

What is the DynoCams 335 camshaft best used for?

The DynoCams 335 camshaft is designed for high-RPM racing applications using Honda GX390 and big block clone engines. It excels in stock-appearing restricted builds and fully modified combinations where top-end horsepower is the priority.


How does the 335 cam compare to the 308, Mod1, and 315 cams?

The 335 is significantly more aggressive than the 308, Mod1, and 315 cams. It features more duration and overlap, sacrificing some low-RPM torque in favor of stronger midrange and top-end power, making it ideal for competitive racing.


Is the DynoCams 335 a low-lift or high-lift cam?

The 335 is considered a moderate-lift cam, positioned between low-lift (.308–.315) and high-lift (.356–.360) camshafts. This makes it versatile for both restricted and high-flow racing combinations.


Can the DynoCams 335 camshaft be used with ratio rocker arms?

Yes. With 1.2 ratio rockers, total valve lift is just over .400”. Using 1.3 ratio rockers increases lift to approximately .435”, which may require cylinder head modifications, higher installed spring height, and stronger valve springs.


What supporting components are required with the 335 cam?

Upgraded dual valve springs are mandatory. A billet connecting rod, billet flywheel, billet rocker arms, chromoly pushrods, and either a stock-appearing modified carburetor or 34mm+ carburetor are strongly recommended.


Does the DynoCams 335 camshaft have a rough idle?

Yes. Idle quality ranges from mildly rough in stock-appearing builds to very aggressive in high-flow billet-head combinations, especially with ratio rockers. Higher clutch stall speeds may be required.


Can the 335 cam be used in high-flow billet head engines?

Yes. In high-flow billet head setups, the 335 focuses the power band toward upper RPM ranges and can act as a form of traction control in lighter chassis by reducing excessive low-RPM torque.


What engines does the DynoCams 335 camshaft fit?

The DynoCams 335 camshaft fits Honda GX390, Predator 420 Wedge (Non-Hemi), and Wildcat 460 big block clone engines with a 16mm (.628”) cam boss.


Does installation require clearance checks?

Yes. As with all high-performance camshafts, cam-to-block and cam-to-rod clearance must be inspected during installation.

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