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Hop Up Kit; GX240, GX270, 9/11hp OHV, & 301; Stage 4
Hop Up Kit; GX240, GX270, 9/11hp OHV, & 301; Stage 4

Our Price: $830.00

Stock Status:In Stock

Part #: STAGE4KIT270

Select Carburator

Carburetor, 24mm Bored 3-Circuit Carb, Gas with Filter Assembly [+$89]
28mm Gas Black Round Slide [+$152]
28mm Flat Slide Mikuni - Gas [+$195]
28mm Flat Slide Mikuni - Methanol [+$240]
Select Flywheel

No Flywheel
Billet Aluminum Flywheel (GX240 & GX270) [+$175]

Description -
Stage 4 Hop Up Kit for GX240, GX270, 9/11hp OHV, and 301
For building a serious a GX270 or 301, the Stage 4 kit starts with a package similar to that of the Stage 3, but adds a ported and milled head with stainless valves, a stud kit, and heavy duty valve train components.

Kit Includes:
  • Fully Ported and Milled Race Head
  • 270 Clone Head (Genuine Honda available upon request for additional cost)
  • High Flow 32mm / 28mm Valves with Lash Caps
  • Dual Springs with Titanium Retainers
  • 306 Race Cam
  • Black Venom Roller Rockers
  • Valve Cover Spacer
  • Chrome Moly Pushrods
  • Choice of Carbs (Or use your own)
  • Billet Rod (+.020" Longer)
  • Offset Timing Key
  • Carb, Head, & Case Gaskets
  • ARP Bolt Kit

*Note: Picture is for reference only. See above description for actual content. These kits are intended for experienced engine builders. Some clearance, fitment, or other engine building "tricks" may be needed. Billet aluminum flywheel REQUIRED.

UT2s series Hondas (2012 & up) or later have a built in rev limiter in the coil and will require a new coil to exceed 4000rpm. The UT2 coils (4 wire) can only be used with stock flywheels. If using a billet flywheel, you must run a UT1 style coil (single wire).
Chinese engines usually have UT1 style coils already. However, some Lifans and 420s have a digital ignition and will need a Honda UT1 coil to run the billet flywheel.

If ordering for a 301, be aware that some engines have large cam journals (.6357), and most 301s have standard cam journals (same as GX270s). If you have a 301, we recommend you measure your cam journals before ordering this. (If in doubt, order the small journal.)

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