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Engine, Racing, Open Modified, Honda GX390
Engine, Racing, Open Modified, Honda GX390

Our Price: $1,817.00

Stock Status:In Stock

Part #: ENG-RAC-GX390-LM

Head Casting (Application)

GX390 Small Port (High Torque, Wide Power)
Large Port (Max HP, High RPM) [+$7.6]
Select Piston/Rings

Aftermarket Cast Flat-Top
OEM Dished Piston
Forged Flat-Top, Standard Bore [+$228]
Forged Flat-Top, 90mm Bore [+$356]
Select Carburator

Carburetor, 24mm Bored 3-Circuit Carb, Gas
Crankshaft Type/Options

OEM Honda Crankshaft
.160" Stroker Crank, Cast, Balanced [+$241]
.200" Billet Stroker Crank [+$408] Adds Labor for Clearacing
Select Rocker Arm Type

1.2 Billet Roller Tip Rockers
1.2 Roller Rockers (Includes Spacer) [+$151]
Select Camshaft

306 HP (Medium to Large Tracks)
306 TQ (Small Tracks)
307 RPM (33mm or Larger Carbs)
Select Flywheel

Billet Aluminum
Small Diameter Aluminum (NA with Electric Start) [+$48]
Billet Aluminum with Digital (PVL) Ignition [+$144]
Add Fuel Tank & Pump Options

Additional Options

Balance Assembly (Included on Strokers) [+$142]

Add Billet Side Cover [+$208] Adds Billet Side Cover to GX390s

Add 40mm Intake [+$54]

Extended Starter Nut for Handheld Starter (No Recoil) [+$23.1]

Description -
Honda GX390 Race Engine
Highest quality big block available!

Engine Includes:

  • Open Element Air Filter Assembly
  • Removal of Governor
  • Advanced Timing
  • Billet Steel Rocker Arms
  • Billet Rod
  • Billet Flywheel
  • UT1 Coil without Rev Limiter
  • Full Ported and Milled Head
  • Stainless Steel Valves (OS on Intake)
  • Aluminum Retainers & Keepers
  • Dual Springs (Single with TQ Cams)
  • Choice of Cams
  • Chrome Moly Pushrods
  • ARP Bolt Kit
  • Choice of Carbs
  • Dyno Tested

Engine Size Options:
  • 88mm (Standard) Bore, Stock Stroke: 390cc
  • 88mm (Standard) Bore, +.160” Stroke: 414cc
  • 88mm (Standard) Bore, +.200” Stroke: 420cc
  • 90mm Bore, Stock Stroke: 407cc
  • 90mm Bore, +.160” Stroke: 433cc
  • 90mm Bore, +.200” Stroke: 440cc
*All race engine orders may take up to 4-6 weeks before shipping.

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

*We offer $10 off shipping costs for each engine if purchasing 3 or more. If shipping cost exceeds $130 in shopping cart, contact us for alternative freight methods. We can typically ship a pallet of engines for $130-$200, depending on delivery location.

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