Home > Engine Family >

Hop Up Kit, 420 Predator OHV & 13/15hp Clone, Stage 4
Hop Up Kit, 420 Predator OHV & 13/15hp Clone, Stage 4

Our Price: $1,085.00

Stock Status:In Stock

Part #: STAGE4KIT420-P

Select Carburator

None (Customer to Supply Carb)
34mm Round Slide Mikuni - Gas [+$183]
34mm Flat Slide Mikuni, Gas [+$211]
33mm Mikuni Pumper, Gas [+$315]
33mm Mikuni Pumper, Methanol [+$422]
Select Flywheel

No Flywheel
Add Aluminum Flywheel - Recoil Start [+$166]
Add Aluminum Flywheel - Electric Start [+$211]

Description -
Stage 4 Hop Up Kit for 420 Predator OHVs & 13/15hp Clones
This kit is similar to our Stage 3, but adds a ported and milled head with stainless valves, a stud kit, and heavy duty valve train components. Allows up to 35+ HP out of a 420 engine. This kit is for OHV engines and will not fit Hemis.

Kit Includes:
  • Fully Ported and Milled Race Head (Genuine Honda Core)
  • High-Torque Genuine Honda Core (The Best!!)
  • High-Flow 36mm / 31mm Valves with Lash Caps
  • Dual Springs with Titanium Retainers
  • 307 Race Cam
  • Black Venom Aluminum Roller Rockers
  • Valve Cover Spacer
  • Chrome Moly Pushrods
  • Choice of Carbs (Or use your own)
  • 90mm Forged Flat-Top Piston with Rings
  • Billet Rod (+.040" Longer)
  • Offset Timing Key
  • Carb, Insulator, Head, and Case Gaskets
  • ARP Bolt Kit

This kit only fits 414 & 420cc (90mm) non-hemi engines. Filter should be sprayed with K&N type oil, especially in dirt applications. Oil not included - click here. Billet aluminum flywheel REQUIRED. These kits are intended for experienced engine builders. Some clearancing, fitment, or other engine building "tricks" may be needed. Picture for reference only. See above description for actual content.

Due to the head work required for this kit, please allow 1 week to ship.

Share your knowledge of this product. Be the first to write a review »