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Hop Up Kit, 420 Hemi, Stage 4
Hop Up Kit, 420 Hemi, Stage 4

Our Price: $967.00
Thanksgiving Sale $870.30
Savings: $96.70

Stock Status:In Stock
Part #: STAGE4KIT420-H

Select Carburator

None (Customer to supply carb)
34mm Round Slide Mikuni - Gas [+$182]
34mm Flat Slide Mikuni - Gas [+$212]
33 Mikuni Pumper - Gas [+$317]
33 Mikuni Pumper - Methanol [+$379]
Select Flywheel

Add Aluminum Flywheel - Recoil Start [+$166]
Add Aluminum Flywheel - Electric Start [+$202]

Description -

The Stage 4 kit starts with package similar to that of the stage 3 but adds a Ported and Milled Head with stainless, stainless valves, stud kit, & HD valve train components. This kit allows up to 35+ HP out of a 420


  • Fully ported and milled HEMI race head
  • High Flow 40mm / 34mm Valves with lash caps
  • Dual Springs with titanium retainers
  • 307 Race Cam
  • Shaft Mounted Roller Rockers
  • Chrome Moly Pushrods
  • Choice of Carbs (or use your own)
  • Forged Flat Top Piston with rings
  • Billet Rod +.040
  • Offset Timing Key
  • Carb, Insulator, Head, Valve Cover, & Case gaskets
  • ARP Bolt Kit

Picture for reference only and may show optional parts. See above description for actual content.

Due to head work required, allow 1 week to ship.

Filter should be sprayed with K&N type oil, especially in dirt applications. Oil not included click here

These kits are intended for experienced engine builders. Some clearancing, fitment, or other engine building "tricks" may be needed.

Billet Aluminum flywheel REQUIRED

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