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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.

List Price: $10.29
Our Price: $8.95
Sale Price: $8.06
Savings: $2.23
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.

List Price: $10.29
Our Price: $8.95
Sale Price: $8.06
Savings: $2.23
Fuel Pump, Aftermarket Walbro Pulse Type Fuel Pump Fuel Pump, Aftermarket Walbro Pulse Type Fuel Pump

Aftermarket Walbro fuel pump for Clone engines, Predator 212cc engines, Ducar small block engines and many big block Honda GX390 engines.

List Price: $11.44
Our Price: $9.95
Sale Price: $8.96
Savings: $2.48
Stock Connecting Rod for Honda GX390 Stock Connecting Rod for Honda GX390

Factory cast aluminum connecting rod for Honda GX390 engine.

List Price: $18.34
Our Price: $15.95
Sale Price: $14.36
Savings: $3.98
Stock Connecting Rod for Honda GX390 Stock Connecting Rod for Honda GX390

Factory cast aluminum connecting rod for Honda GX390 engine.

List Price: $18.34
Our Price: $15.95
Sale Price: $14.36
Savings: $3.98
Air Filter Adapter for Mikuni 38mm Super BN Carburetor Air Filter Adapter for Mikuni 38mm Super BN Carburetor

Bullfrog Performance Products air filter adapter for Mikuni 38mm Super BN carburetor.

List Price: $38.95
Your Price $27.50
Sale Price: $19.95
Savings: $19.00
Stainless Steel Intake Valve for Honda GX390, 35mm Head Stainless Steel Intake Valve for Honda GX390, 35mm Head

Bullfrog Performance Products stainless steel intake valve for Honda GX390 big block engines. This valve has 35mm head diameter which is stock size for the Honda GX390 engine. We do offer multi angle valve seat machining to get the most flow from this 35mm valve. We highly recommend this valve when using high lift aftermarket racing cams to prevent valvetrain failure.
This valve will give you the required valve spring installed height to get proper spring rate and coil bind clearance when using high lift aftermarket camshafts.

List Price: $25.88
Our Price: $22.50
Sale Price: $20.25
Savings: $5.63
Stainless Steel Exhaust Valve 31mm Head for Honda GX390 Stainless Steel Exhaust Valve 31mm Head for Honda GX390

Bullfrog Performance Products stainless steel exhaust valve for Honda GX390 engines. The stock size exhaust valve is a 31mm head diameter in a Honda GX390. We offer cylinder head machining services to maximize head flow for better performance.
We highly recommend this valve when using high lift aftermarket racing cams to prevent valvetrain failure. Our valve will put your valve spring installed height and coil bind clearances in the proper range when using our billet valve spring retainer kit.

List Price: $25.88
Our Price: $22.50
Sale Price: $20.25
Savings: $5.63
Stainless Steel Intake Valve for Honda GX390, 35mm Head Stainless Steel Intake Valve for Honda GX390, 35mm Head

Bullfrog Performance Products stainless steel intake valve for Honda GX390 big block engines. This valve has 35mm head diameter which is stock size for the Honda GX390 engine. We do offer multi angle valve seat machining to get the most flow from this 35mm valve. We highly recommend this valve when using high lift aftermarket racing cams to prevent valvetrain failure.
This valve will give you the required valve spring installed height to get proper spring rate and coil bind clearance when using high lift aftermarket camshafts.

List Price: $25.88
Our Price: $22.50
Sale Price: $20.25
Savings: $5.63
Stainless Steel Exhaust Valve 31mm Head for Honda GX390 Stainless Steel Exhaust Valve 31mm Head for Honda GX390

Bullfrog Performance Products stainless steel exhaust valve for Honda GX390 engines. The stock size exhaust valve is a 31mm head diameter in a Honda GX390. We offer cylinder head machining services to maximize head flow for better performance.
We highly recommend this valve when using high lift aftermarket racing cams to prevent valvetrain failure. Our valve will put your valve spring installed height and coil bind clearances in the proper range when using our billet valve spring retainer kit.

List Price: $25.88
Our Price: $22.50
Sale Price: $20.25
Savings: $5.63
Bullfrog Pro Velocity High Performance Air Filter Kit for Honda GX390 Bullfrog Pro Velocity High Performance Air Filter Kit for Honda GX390

Our Pro Velocity high performance air filter kit fits Honda GX340, GX390, Predator 420cc and 460cc big block clone engines. Upgrade your go kart, mini bike or drift trike with our high performance air filter kit. Our kit includes the following items:


  • High flow racing style air filter 4" filter length
  • Foam Pre-Filter
  • Radiused air filter adapter
  • Choke hold bracket

Our Price: $44.95
Tachometer, Vegas Carts 0-8000 RPM Tachometer, Vegas Carts 0-8000 RPM

A great addition to any Big Block Kit or Performance Go-Kart where a sweeping analog Tachometer is desired. This Tachometer has been specifically designed for small engines with a magneto ignition such as the Predator 212cc, GX390 or 420-460cc Clone and V-Twins such as the Briggs Vanguard or Predator 670cc. Hooks up to the Kill-Wire on the ignition coil.

RPMs from 0-8000. This gauge is equipped with a Backlight.

Mounting bracket for steering column and wiring pigtail included.

85mm Diameter (3.33")

Fully Adjustable & Tunable

Excellent Alternative to the EQUUS 8068.


List Price: $57.44
Our Price: $49.95
Savings: $7.49
Billet Intake Manifold 38mm Super BN Carburetor to Honda GX390 Billet Intake Manifold 38mm Super BN Carburetor to Honda GX390

Bullfrog Performance Products exclusive billet intake manifold adapts Mikuni 38mm Super BN carburetors to Honda GX390 big block engines.  Will also adapt the Mikuni 36mm and 38mm round slide carburetors when using our rubber mounting boot.  Our intake has multiple bolt patterns and incorporates our exclusive throttle mounting bracket with our intake design.

List Price: $66.70
Our Price: $58.00
Sale Price: $52.20
Savings: $14.50
Billet Intake Manifold, 38mm Super BN Carburetor to Honda GX390 Billet Intake Manifold, 38mm Super BN Carburetor to Honda GX390

Our billet intake manifold adapts Mikuni 38mm SBN carburetors to your Honda GX390 big block clone engine. This intake will also work with round slide and flat slide carburetors using a boot that bolts to our intake manifold (sold separately). Our billet aluminum intake has an 1/8" npt port for your fuel pump pulse line and includes the throttle cable bracket integrated into the intake.

List Price: $67.79
Our Price: $58.95
Sale Price: $53.06
Savings: $14.73
Billet Valve Cover, Honda GX390 Big Block w/Cooling Fins Billet Valve Cover, Honda GX390 Big Block w/Cooling Fins

Our billet valve cover for the big block engine features our unique integral cooling fins for additional valve spring chamber cooling. Our billet valve cover is the lightest cover on the market and includes a reed valve system built into the cover design. You can throw away your stock valve cover gasket as our cover comes with an o-ring seal that promotes better clamping force and eliminates oil leaks. The other billet valve covers on the market do not have the machining time put into their valve cover to make them work as a bolt on piece. Our cover is taller than the factory valve cover so it will clear any roller rocker arm on the market. You will also receive our custom machined aluminum crankcase breather fittings.

Bullfrog Performance Products billet valve cover fits big block engines listed below:

  • Honda GX240
  • Honda GX270
  • Honda GX340
  • Honda GX390
  • Powerhorse 414cc
  • Vegas Carts 460cc
  • LCT 414cc
Our big block billet valve cover will only fit the wedge style head and it will not fit the hemi heads on Predator 420cc.

List Price: $172.44
Our Price: $149.95
Sale Price: $134.96
Savings: $37.48
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.

List Price: $172.44
Our Price: $149.95
Sale Price: $134.96
Savings: $37.48
Valve, Titanium Intake Valve, 42mm Head Diameter Big Block Valve, Titanium Intake Valve, 42mm Head Diameter Big Block

Bullfrog Performance Products titanium valve has 42mm head diameter. Will work in Honda GX390, 420cc, 440cc and 460cc and 500cc big block engines. This valve will require machining to your cylinder head for proper fit. We offer machining services to fit our valve in your cylinder head.

List Price: $172.44
Our Price: $149.95
Sale Price: $134.96
Savings: $37.48
Valve, Titanium Intake Valve, 45mm Head Diameter Big Block Valve, Titanium Intake Valve, 45mm Head Diameter Big Block

Bullfrog Performance Products titanium valve has 45mm head diameter. Will work in Honda GX390, 420cc, 440cc and 460cc and 500cc big block engines. This valve will require machining to your cylinder head for proper fit. We offer machining services to fit our valve in your cylinder head.

List Price: $172.44
Our Price: $149.95
Sale Price: $134.96
Savings: $37.48
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.

List Price: $172.44
Our Price: $149.95
Sale Price: $134.96
Savings: $37.48
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.

List Price: $172.44
Our Price: $149.95
Sale Price: $134.96
Savings: $37.48
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.

List Price: $172.44
Our Price: $149.95
Sale Price: $134.96
Savings: $37.48
GX390 Big Block Bored Carburetor 23.5mm Venturi GX390 Big Block Bored Carburetor 23.5mm Venturi

Bullfrog Performance Products big block bored performance carburetor.  Our carburetor is CNC bored to obtain consistant max air flow.  Our carb has extensive carb air horn modifications along with the fuel circuits re-worked for the best transient and wide open throttle use.  Select if you need gas or methanol / alky fuel.

List Price: $171.35
Our Price: $149.00
Savings: $22.35
Forged Dome Piston Kit 90mm Bore, 1.100" Comp Height Forged Dome Piston Kit 90mm Bore, 1.100" Comp Height

Bullfrog Performance Products forged dome piston kit for the Predator 420cc engines.  This forged piston kit is a 90mm standard bore with a 1.100" compression height.  Our piston fits our 4.440" length billet rod or the ARC Racing connecting rods.

List Price: $224.25
Our Price: $195.00
Sale Price: $175.50
Savings: $48.75
Bullfrog Torq-N-Rev Big Block Billet Connecting Rod GX390 Bullfrog Torq-N-Rev Big Block Billet Connecting Rod GX390

Bullfrog Performance Products billet connecting rod fits Honda GX340, GX390, 420cc clone, 440cc clone and 460cc big block engines.  Our Torq-N-Rev billet connecting rod is CNC machined from 7075 T-6 billet aluminum and includes babbit rod bearing set and ARP rod bolts and washers. This billet rod is 4.440" center to center length.  Heavy duty rod cap and beam design for the most extreme engine setups.  Fits stock piston pin or aftermarket pistons with the standard piston pin diameter.

List Price: $228.24
Our Price: $198.47
Sale Price: $178.62
Savings: $49.62
Bullfrog Torq-N-Rev Billet Connecting Rod, Honda GX390 4.610" +.200" Longer Than Stock Bullfrog Torq-N-Rev Billet Connecting Rod, Honda GX390 4.610" +.200" Longer Than Stock

Bullfrog Performance Products Torq-N-Rev billet connecting rod is manufactured from billet 7075 T-6 aluminum.  Our billet connecting rod includes rod bearings and setup with ARP rod bolts. Our billet rod is +.200" longer than stock length of 4.610" center to center length.  Works with our forged big block piston kits with .900" compression height.

List Price: $228.24
Our Price: $198.47
Sale Price: $178.62
Savings: $49.62
Bullfrog Torq-N-Rev Big Block Billet Connecting Rod GX390 Bullfrog Torq-N-Rev Big Block Billet Connecting Rod GX390

Bullfrog Performance Products billet connecting rod fits Honda GX340, GX390, 420cc clone, 440cc clone and 460cc big block engines.  Our Torq-N-Rev billet connecting rod is CNC machined from 7075 T-6 billet aluminum and includes babbit rod bearing set and ARP rod bolts and washers. This billet rod is 4.440" center to center length.  Heavy duty rod cap and beam design for the most extreme engine setups.  Fits stock piston pin or aftermarket pistons with the standard piston pin diameter.

List Price: $228.24
Our Price: $198.47
Sale Price: $178.62
Savings: $49.62
Bullfrog Torq-N-Rev Billet Connecting Rod, Honda GX390 4.610" +.200" Longer Than Stock Bullfrog Torq-N-Rev Billet Connecting Rod, Honda GX390 4.610" +.200" Longer Than Stock

Bullfrog Performance Products Torq-N-Rev billet connecting rod is manufactured from billet 7075 T-6 aluminum.  Our billet connecting rod includes rod bearings and setup with ARP rod bolts. Our billet rod is +.200" longer than stock length of 4.610" center to center length.  Works with our forged big block piston kits with .900" compression height.

List Price: $228.24
Our Price: $198.47
Sale Price: $178.62
Savings: $49.62