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Big Block Clones LLC

Shredder Cylinder Head - STAGE 1 - For GX200 and Clones - Predator

Shredder Cylinder Head - STAGE 1 - For GX200 and Clones - Predator

Regular price $109.95 USD
Regular price Sale price $109.95 USD
Sale Sold out
Bare or Assembled?
Chamber Volume

Full specs are listed at the bottom of this page. 

**FITS ALL ENGINES WITH GX200 HEAD BOLT PATTERN**

Want to bolt more horsepower onto your small block clone engine? The Shredder head is a high performance sand casting with much better ports than stock style die cast clone heads.  The Stage 1 Shredder head flows up to 35% more air than OEM 212/224cc cylinder heads. This head can be purchased as a bare casting or a completed head ready to bolt onto your 10mm or 11mm dowel block. 

With our bare or complete Stage 1 head you'll get a ported Shredder casting that has been flowed on our bench to guarantee horsepower gains above a standard Shredder. With a complete Stage 1 Shredder you'll also get a 28.5mm stainless steel intake valve, 24mm stainless steel exhaust valve, both have 5.5mm stems, 13cc, 15.5cc, or 18cc chamber, 1.2:1 ratio heavy-duty stamped 0.095" thick steel rocker arms, billet aluminum retainers with high groove split keepers, 37lb single springs, and a billet steel guide plate. We have test fitted dual valve springs up to 60lb rates with no fitment issues in the spring pocket. This is a killer upgrade for your engine, and if paired with a 308 or larger cam and a 28mm or larger carburetor you'll see 20+hp. 

If you are bolting one of these heads on any non-hemi Predator or other Rato engine you'll need our stepped head dowel pins to adapt the 11mm holes in the block to the 10mm holes in these heads.

Sold in pairs here:

Stepped Head Dowel Pin Set - 10mm to 11mm

SHREDDER CYLINDER HEAD SPECS STOCK - STAGE 1 - 18cc, 15.5cc, or 13cc Chamber
Stock Flow in CFM 35% over standard D port (Approximate, depends on flowbench used, ours says 96CFM)
Maximum Horsepower Supported Stock 20HP+
Recommended Cam 308 or 356 Depending on application
Recommended Carburetor Mikuni PE, PZ, or PWK 26mm or larger
Minimum Recommended Bore 68mm 
Chamber Volume 18cc (10.5:1 Static Compression Ratio on a 212 Predator with piston at zero deck) 15.5cc, or 13cc
Valve Material Stainless Steel (both)
Intake Runner Volume 33cc
Exhaust Runner Volume 27cc
Intake Valve Weight 29 grams
Intake Valve Head Diameter  28.5mm
Intake Valve Stem Diameter  5.5mm
Intake Valve Total Length 66mm
Exhaust Valve Weight 22.6 grams
Exhaust Valve Head Diameter  24mm
Exhaust Valve Stem Diameter 5.5mm
Exhaust Valve Total Length 65.15mm
Valve Spring Rate 37LB/IN
Valve Spring Retainer Material Billet aluminum
Valve Spring Retainer Weight 4 grams each
Valve Spring Keeper Style Automotive Style Split with High Groove
Valve Spring Keeper Material Steel
Valve Spring Keeper Weight 0.65 grams each
Dowel Pin Diameter 10mm (We sell 10mm x 11mm stepped dowel pins)
Head Bolt Pattern Standard Small Block Clone
Intake Bolt Spacing Pattern Mikuni 48mm
Intake Bolt Size and Thread M6x1mm
Exhaust Bolt Pattern Spacing 47mm (like a HF 224)
Exhaust Bolt Size and Thread M8x1.25 (Standard Clone)
Rocker Arms 0.095" thick stamped steel 1.2:1 Ratio
Rocker Arm Weight 25.3 grams each
Pushrod Guide Plate Billet steel
Rocker Arm Studs Screw-In Steel M6x0.50mm/M8x1.25mm
Weight (bare casting) 2.342lbs
Valve Seat Angles Three
Valve Seat Material Steel
Valve Guide Material Steel
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