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Wildcat WC946 Assembly with 31mm/25mm SS Valves, 26lb Springs & Aluminum Retainers
Wildcat WC946 Non-Hemi 31mm/25mm Cylinder Head Assembly
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Wildcat WC946 Assembly with 31mm/25mm SS Valves, 26lb Springs & Aluminum Retainers

Part Number: WC946-2
1 Review(s)
Online Price: $164.99
Wildcat WC946 Non-Hemi Cylinder Head Assembly | Big Valve Performance
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Description

Wildcat WC946 Non-Hemi Cylinder Head – Big Valve Cast Head for Clone, Predator & Tillotson Engines


The Wildcat WC946 Non-Hemi Cylinder Head is a high-performance upgrade engineered for racers, builders, and enthusiasts seeking maximum airflow, compression, and durability from a cast head platform. Designed to bridge the gap between affordability and performance, this head is ideal for stock-appearing classes, budget-conscious builds, and experienced engine tuners alike.


Important Installation & Compatibility Notes

Before ordering or installing the WC946, please review the following:

  • Valve Seat Compatibility: This cylinder head is designed for standard-length 31mm intake and 25mm exhaust valves.
    • To use 32mm intake or 27mm exhaust valves, new seat angles must be cut.
  • Install Height & Spring Pressure:
    • Using standard-length valves, install height is approximately .825" for 26 lbs seat pressure (without 272 springs).
    • Max recommended valve lift: .310" — exceeding this can cause coil bind or mechanical interference.
    • Always confirm spring pressure requirements with your camshaft manufacturer to avoid valve float or premature wear.
  • This version comes pre-assembled with:
    - Valves
    - 26 lb Valve Springs
    - Retainers
  • Dual Valve Spring Installation:
    • Requires cutting spring pockets.
    • Use longer valves for optimal geometry and clearance.
  • Note: Valve seals are not included with this cylinder head.

For installation details, porting tips, and tuning instructions, refer to our Big Valve Cylinder Head Guide.


Who Is the Wildcat WC946 For?

We developed the WC946 with three key groups in mind:

  • 1. Bolt-On Budget Builders

Builders with limited tools or experience can enjoy increased compression and airflow at a price nearly 50% less than previous non-ported big valve heads — and far more affordable than billet or premium cast alternatives.

  • 2. Stock Appearing Class Racers

Unlike heads that aren’t legal or compatible (like EVO or DTV Shredder), or heads that require extensive machining (like the Gage Warhead), the WC946 delivers enhanced performance while maintaining stock appearance and fitment.

  • 3. Engine & Cylinder Head Builders

This head is a competitive option when billet heads are restricted by class rules or cost. It offers more material to work with, better airflow out of the box, and a solid starting point for professional-level porting and tuning.


Wildcat WC946 Cylinder Head – Performance Features

1. Bigger Valves for Better Flow

  • Designed for 31mm intake / 25mm exhaust stainless steel valves.
  • 5mm valve guides help reduce weight and friction — ideal for high-RPM builds.

2. 18cc Combustion Chamber

  • Raises compression in modern 223cc+ clone engines.
  • Kidney-shaped chamber reduces quench distance and minimizes decking for methanol/race fuel engines.
  • Ideal balance for high-compression pump gas or race builds.

3. Optimized Spark Plug Location

  • Plug moved closer to the exhaust side for improved combustion and clearance for larger valves (up to 36mm).
  • More central spark plug position improves flame travel and efficiency.

4. Enlarged Intake & Exhaust Ports

  • Stock port: ~0.910" x 0.920"
  • WC946 port: 1.035" wide x 0.990" tall — increased cross-sectional area supports larger carburetors and boosts flow potential with minimal port work.

5. Veined Valve Guide Support

  • Adds material near the guide for custom port shaping.
  • Increases flexibility for tuners to refine port angles, direction, and short-side radius.

6. Reinforced Porting Areas

  • Extra material added between intake walls and rocker stud boss.
  • Enlarged outer port bowl walls help prevent breakouts during aggressive porting.
  • Proven 99 CFM at .350" lift without welding or epoxy — even more airflow with oil hole filled.

7. Stock Valve Cover Compatibility

  • Valve train area is 0.150" taller than standard non-hemi heads, providing clearance for Champion or roller rockers.
  • May allow use of unmodified stock valve covers.

8. Stronger Cast Design & Improved Cooling

  • Thicker fins and more internal material for better strength and heat dissipation.
  • Built to handle high-compression and high-RPM abuse without distortion or cracking.


Summary

The Wildcat WC946 Non-Hemi Cylinder Head is a powerful upgrade for Clone, Predator, and Tillotson performance engines. It delivers big-valve performance, advanced porting potential, and stock-legal appearance, all at an unbeatable price point.


Whether you’re building a box-stock racer or a custom-tuned methanol monster, the WC946 provides the performance, flexibility, and durability you need.

FAQ

Q1: What engines is the Wildcat WC946 compatible with?

A: The WC946 is designed for use with Clone, Predator 212, and Tillotson small block engines in non-hemi configurations. It fits most stock-appearing class setups with minimal modifications.


Q2: What size valves can I run with this cylinder head?

A: It’s machined for 31mm intake and 25mm exhaust valves (standard length). You can run 32mm or 27mm valves, but you’ll need to cut new seat angles to fit them.


Q3: What is the recommended max valve lift?

A: The maximum recommended valve lift is .310 inches. Exceeding this limit may cause coil bind or interference, depending on your spring and cam setup.


Q4: Are valve seals included with the WC946 head?

A: No, valve seals are not included with this version of the head.


Q5: Can I install dual valve springs?

A: Yes, but you’ll need to cut spring pockets and use longer valves to accommodate dual springs. This head is designed with additional material to support these upgrades.


Q6: What’s included with this cylinder head?

A: This version comes pre-assembled with valves, 26 lb springs, and retainers installed. It’s ready for installation with standard-length valves.


Q7: Will this head work with stock valve covers?

A: In most cases, yes. The head is approximately .150” taller than standard non-hemi heads, which allows clearance for Champion and roller rockers — and often still works with unmodified stock valve covers.


Q8: How much flow can I get from this head?

A: With proper porting, we’ve seen up to 99 CFM at .400 lift without breaking through the port or using epoxy. With additional modifications (like filling the oil hole), 100+ CFM is achievable.


Q9: Is this head legal for stock-appearing race classes?

A: Yes, the WC946 is designed to qualify as a stock head for many stock-appearing racing classes while offering significant performance advantages.


Q10: Where can I find installation and setup instructions?

A: You can find detailed instructions and setup guidance on our website here:
Big Valve Cylinder Head Setup Guide

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Customer Reviews

Great Head
Easy plug-and-play head with a lot of potential. So much top end power and even more support for porting and dual valve spring setups
Did you find this helpful?  3 of 3 Found Helpful
Reviewed by: (Verified Buyer)  from Bowling Green on 6/23/2024
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