Home > Shop by Engine > Honda GX390 / Predator 420cc > Honda GX390 Performance Parts > Shortblock Parts
Sort By:
Page of 1
Crankshaft Oil Seal for Honda GX390 Crankshaft Oil Seal for Honda GX390

Crankshaft oil seal fits Honda GX340, GX390, 420cc and 460cc engines.  Use this seal on both the PTO or Flywheel side.  Engine requires two per engine so order a quantity of two per engine.

Our Price: $5.00
ARP Side Cover Bolt for Honda GX390, 460cc ARP Side Cover Bolt for Honda GX390, 460cc

ARP crankcase side cover bolt fits Honda GX340, GX390, 420cc, and 460cc big block clone engines.  Order a total of 7 bolts for Honda GX340 and GX390.  Order a total of 10 bolts for 460cc big block clone engines.

Your Price $5.45
Dipstick for Honda GX390, 460cc Big Block Dipstick for Honda GX390, 460cc Big Block

Dipstick fits Honda GX240, GX270, GX340, GX390, GX440 and 460cc big block engines.

Our Price: $6.00
Oil Fill Plug for Honda GX390, 460cc Big Block Oil Fill Plug for Honda GX390, 460cc Big Block

Oil fill plug fits Honda GX240, GX270, GX340, GX390, 440cc and 460cc big block engine.

Our Price: $6.00
Solid Side Cover Dowel Pin Kit for Honda GX390 (Includes 2 dowels) Solid Side Cover Dowel Pin Kit for Honda GX390 (Includes 2 dowels)

Solid side cover dowel pin fits Honda GX390 engines.  Order two per engine.

Our Price: $8.00
Side Cover Gasket, 7 Bolt Side Cover Honda GX390, 420cc Big Block Side Cover Gasket, 7 Bolt Side Cover Honda GX390, 420cc Big Block

Honda GX390 side cover gasket.  Fits all 7 bolt GX390 engines and 7 bolt 420cc big block engines.

Our Price: $10.00
Side Cover Gasket, 10 Bolt 460cc Big Block Side Cover Gasket, 10 Bolt 460cc Big Block

10 bolt side cover gasket for the 440cc and 460cc 10 bolt side cover

Our Price: $10.00
Main Bearing for Honda GX390, 420cc, 460cc Main Bearing for Honda GX390, 420cc, 460cc

Main bearing for Honda GX340, GX390, 420cc and 460cc engines.   Requires two per engine.  (These are sold individually one bearing).

Our Price: $12.00
Copper Head Gasket, Honda GX390, 460cc, 500cc Big Block Copper Head Gasket, Honda GX390, 460cc, 500cc Big Block

Copper head gasket available in a variety of bore and thickness ranges for the big block Honda GX390, 460cc, 500cc engines.  Select the gasket below that fits your build:

Our Price: $18.00
Sale Price: $12.00
Savings: $6.00
Head Gasket fits Honda GX390 .010" Thick Head Gasket fits Honda GX390 .010" Thick

This head gasket fits Honda GX390 88mm bore and is .010" thick.

Our Price: $12.95
Head Gasket fits Honda GX390 88mm Bore, Graphite Head Gasket fits Honda GX390 88mm Bore, Graphite

This head gasket is a graphite head gasket and will fit the Honda GX390 engine with 88mm bore.

Our Price: $15.00
Electric Starter Block Off Plate for Honda GX390, GX440 Electric Starter Block Off Plate for Honda GX390, GX440

Electric starter block off plate fits Honda GX340, GX390, and 460cc big block clone engines.

Our Price: $15.00
Gasket Set, Honda GX390 Gasket Set, Honda GX390

Gasket set for Honda GX390 engines.

Our Price: $15.00
Head Gasket GX390 MLS Head Gasket GX390 MLS

Multi Layer Steel head gasket that fits the Honda GX390 engine.  Gasket has 89mm bore to fit the stock bore size on the Honda GX390.

Our Price: $15.00
Magnetic Oil Drain Plug, Honda GX390 Magnetic Oil Drain Plug, Honda GX390

Bullfrog Performance Products magnetic oil drain plug for Honda GX390 and big block clones.  Billet aluminum drain plug includes the copper gasket.  Our plug is a nice upgrade to catch any signs of engine trouble by catching the magnetic particles that may be in your engine oil.

Our Price: $19.00
Head Gasket Fits GX440 and 460cc Engines 92mm Bore MLS Head Gasket Fits GX440 and 460cc Engines 92mm Bore MLS

Our Multi Layer Steel (MLS) head gasket fits the 460cc big block clone engines with 92mm bore size.

Our Price: $20.00
Rod Bearing Set for Honda GX390 ARC Racing Rods Rod Bearing Set for Honda GX390 ARC Racing Rods

ARC Racing connecting rod bearing set for ARC Racing billet connecting rods part number 6272 and 6274 Honda GX390.

Our Price: $23.00
Rod Bearing Set for Bullfrog Performance Products GX390 Rod Rod Bearing Set for Bullfrog Performance Products GX390 Rod

Rod bearing set for our Bullfrog Performance Products GX390 billet connecting rod.

Your Price $24.95
Engine Mount, 460cc Big Block Engine Mount, 460cc Big Block

Bullfrog Performance Products big block engine mount plate will fit 460cc engine base plate dimensions that are longer than the Honda GX390. Machined from billet aluminum and ready to bolt to a Burris Racing BMC541 or BMC542 chassis mounts and many other Burris Racing kart chassis mounts.

THIS MOUNTING PLATE WILL ONLY FIT THE 460cc VEGAS CARTS STYLE ENGINE!

Our Price: $65.00
Sale Price: $38.00
Savings: $27.00
Side Cover, 10 Bolt Side Cover for 460cc Engines Side Cover, 10 Bolt Side Cover for 460cc Engines

10 bolt side cover for 460cc big block clone engines.

Our Price: $45.00
Crankcase Cover Gasket and ARP Bolt Kit Honda GX340, GX390 Crankcase Cover Gasket and ARP Bolt Kit Honda GX340, GX390

Crankcase cover gasket and ARP side cover bolt fastener kit for the Honda GX340 and GX390 side cover. Changing out a cam or making internal repairs or just plain building a new engine from scratch then you will need our kit to get maximum seal and clamp load your side cover needs to hold the bottom end together.

Our Price: $59.50
Cylinder Block, 460cc 10 Bolt 92mm Bore Cylinder Block, 460cc 10 Bolt 92mm Bore

Bullfrog Performance Products 92mm 460cc cylinder block.  Our block features a 10 bolt side cover and a tall deck to allow for even more stroke without the piston popping up above the deck.  Our cylinder block accepts all Honda GX390 internals, including camshaft, lifters and cranks seals.

Our Price: $130.00
Billet Connecting Rod ARC Racing for Honda GX390 4.410" Billet Connecting Rod ARC Racing for Honda GX390 4.410"

ARC Racing billet connecting rod for Honda GX390 engines.  Includes rod bearings and rod bolts.

Our Price: $150.00
Billet Connecting Rod ARC Racing for Honda GX390 4.450" Billet Connecting Rod ARC Racing for Honda GX390 4.450"

ARC Racing billet connecting rod for the Honda GX390.  This rod is 4.450" center to center length and comes with rod bearings and rod bolts.

Our Price: $150.00
Billet Crankshaft, Big Block Honda GX390, +.200 Stroker Billet Crankshaft, Big Block Honda GX390, +.200 Stroker

New from ARC Racing is a billet crankshaft for the big block clone 460cc or Honda GX390 engine.  This billet crankshaft has +.200" more stroke than the Honda GX390 factory crankshaft. Crank stroke is 69mm.  If using this crankshaft in the Honda GX390 block you will need to mill the top of your piston to achieve the correct deck height.

Our Price: $500.00
500cc Big Block Racing Engine, Longblock 500cc Big Block Racing Engine, Longblock

Bullfrog Performance Products is the first in the industry to offer a 500cc big block racing engine package. We are always innovating and bringing new engine packages to the small engine performance enthusiast. Our 500cc longblock is custom built and comes with the following high quality components:

  • Bullfrog Performance Products custom Big Bore tall deck cylinder block for stroker crank applications
  • Bullfrog Performance Products custom forged piston and low drag ring kit
  • Head Dowels
  • Side Cover 10-Bolt
  • ARP side cover bolt kit
  • Solid side cover dowel pins
  • Dipstick and oil fill cap
  • Cranksaft oil seals made from Viton material for higher operating temperatures
  • Roller main bearings
  • Custom stroker crankshaft
  • Bullfrog Performance Products billet connecting rod kit
  • ARP rod bolts
  • Babbit Rod Bearings
  • Victor Reinz big bore fire ring style head gasket
  • Bullfrog Performance Products custom head package
    • GX390 aftermarket cylinder head
    • Big valve package
    • Custom multi-angle valve job
    • Ported, polished and flow tested head
    • Dual valve spring package
    • Billet valve spring retainer kit
    • Chrome moly pushrod kit
    • Roller rocker arm package
    • ARP head bolt kit
    • Performance cam and lifter kit
    • Billet valve cover with integral cooling fins
    • Engine is a longblock

Our Price: $2,649.00