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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 440cc and 460cc big block clone engines with 92mm bore size.

Our Price: $20.00
Stainless Steel Intake Valve for 460cc, 40mm Head Stainless Steel Intake Valve for 460cc, 40mm Head

Bullfrog Performance Products stainless steel intake valve fits 460cc big block engines when cylinder head is machined for this valve size. We offer cylinder head machining to install this larger valve into the 460cc cylinder head. The valve head diameter is 40mm, which is 5mm larger than the stock 460cc valve. We highly recommend this valve when using high lift aftermarket racing cams to prevent valvetrain failure.
Be sure to include our billet aluminum or titanium valve spring retainer kit with our valve.

Our Price: $20.00
Stainless Steel Exhaust Valve 33mm Head Diameter GX390 Stainless Steel Exhaust Valve 33mm Head Diameter GX390

Bullfrog Performance Products stainless steel exhaust valve for Honda GX390 engines when valve seat is machined to 33mm valve head diameter. We offer cylinder head machining services to install our 33mm exhaust valve in your cylinder head.
We highly recommend this valve when using high lift aftermarket racing cams to prevent valvetrain failure.
Head Diameter = 33mm
Valve Overall Length = 3.650"
Tip Length = .130"

Be sure to purchase our titanium retainer kit or billet aluminum retainer kit to work with this valve!

Our Price: $20.00
Stainless Steel Intake Valve for Honda GX390, 36mm Head Stainless Steel Intake Valve for Honda GX390, 36mm Head

Bullfrog Performance Products stainless steel intake valve for Honda GX390 big block engines. This valve has 36mm head diameter. We do offer multi angle valve seat machining to get the most flow from this 36mm 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.

Our Price: $25.00
Titanium Valve Spring Retainer Kit Honda GX390 Big Block Titanium Valve Spring Retainer Kit Honda GX390 Big Block

Titanium valve spring retainer kit that fits the big block Honda GX240, GX270, GX340, GX390, 420cc Predator (non-hemi), 460cc Vegas Carts engine (equipped with our stainless steel valves). This titanium valve spring retainer kit includes (2) titanium valve spring retainers and a set of our automotive bead lock style valve locks. Our retainers will fit the single or dual springs out on the market and we also carry them in stock at Bullfrog Performance Products warehouse.

Our Price: $40.00
2 into 1 Collector for Honda GX670 and Predator 670cc 2 into 1 Collector for Honda GX670 and Predator 670cc

Bullfrog Performance Products V-Twin 2 into 1 collector kit will work with our Honda GX670 / Predator 670cc and Honda GX630/GX690 V-Twin header kits

Our Price: $43.95
Pushrod Kit, Chrome Moly Big Block 6.5" Length x 5/16" OD x 6mm Ball Ends Pushrod Kit, Chrome Moly Big Block 6.5" Length x 5/16" OD x 6mm Ball Ends

Our chrome moly pushrod kit consists of two chrome moly pushrods that fit the big block Honda GX390 style engines.  Our pushrods measure 6.5" in length and are 5/16" OD with 6mm ball ends (factory ball end size).  These pushrods come assembled ready to drop in your big block clone or Honda GX390 racing engine.

Our Price: $45.00
Stainless Steel Valve and Titanium Retainer Kit GX390 Stainless Steel Valve and Titanium Retainer Kit GX390

Our big valve kit for the Honda GX340 / GX390 includes the following components:


  • 40mm head stainless steel intake valve 3.650" length
  • 33mm head stainless steel exhaust valve 3.650" length
  • Titanium valve spring retainers
  • Automotive bead lock style valve locks
Our kit does require your head to be machined to fit these valve head sizes. We do offer cylinder head machining at our facility and can machine your cylinder head or purchase a fully machined cylinder head from us ready to go.

Our Price: $60.00
Hot Coil for Honda GX390 Big Block Clone-Black Wire Color Hot Coil for Honda GX390 Big Block Clone-Black Wire Color

Bullfrog Performance Products Hot Coil is designed for the Honda GX340, GX390 and Big Block Clone racing engines that need that hotter spark for your racing engine.  Our coil and wire package has a built-in capacitor that boosts the spark at your plug for increased throttle response and power!

Our Price: $78.00
Hot Coil for Honda GX390 Big Block Clone-Blue Wire Color Hot Coil for Honda GX390 Big Block Clone-Blue Wire Color

Bullfrog Performance Products Hot Coil is designed for the Honda GX340, GX390 and Big Block Clone racing engines that need that hotter spark for your racing engine.  Our coil and wire package has a built-in capacitor that boosts the spark at your plug for increased throttle response and power!

Our Price: $78.00
Hot Coil for Honda GX390 Big Block Clone-Red Wire Color Hot Coil for Honda GX390 Big Block Clone-Red Wire Color

Bullfrog Performance Products Hot Coil is designed for the Honda GX340, GX390 and Big Block Clone racing engines that need that hotter spark for your racing engine.  Our coil and wire package has a built-in capacitor that boosts the spark at your plug for increased throttle response and power!

Our Price: $78.00
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. 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.

Our Price: $145.00
Bullfrog Torq-N-Rev Big Block Billet Connecting Rod GX390 4.450" Length Bullfrog Torq-N-Rev Big Block Billet Connecting Rod GX390 4.450" Length

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 4.450" 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.

Our Price: $159.00
Bullfrog Torq-N-Rev Billet Connecting Rod, Honda GX390 4.650" +.200" Longer Than Stock Bullfrog Torq-N-Rev Billet Connecting Rod, Honda GX390 4.650" +.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 4.650" center to center length.  Works with our forged big block piston kits with .900" compression height.

Our Price: $159.00
GPS DIGITAL SPEEDOMETER TEMPERATURE GAUGE GPS DIGITAL SPEEDOMETER TEMPERATURE GAUGE

  • Multi Function GPS Speedometer. Everything you need to monitor speed and distance. Measures engine temp, and maintenance intervals.
  • Measures current speed, average speed, max speed, trip meter(resettable), total mileage, air temperature, engine temp, battery voltage, clock (trip time/stop watch), and maintenance intervals.
  • Easy installation. Handle bar mount included. Hardwired power connection and temperature sensor. Built-in rechargeable Lithium battery. Operation Manual included.
  • Universal fit. Will fit all motorcycle handle bars, ATV, UTV, Can-AM, Rzr, and any other automobile, offroad vehicles and marine vessels.
  • IP67 Waterproof rating. Shockproof, weatherproof, built for extreme condition.

Our Price: $160.00
Clutch, Bully Turbo 1" (less drive gear) Clutch, Bully Turbo 1" (less drive gear)

Bully Turbo 1" clutch for GX390, 460cc and V-Twin big block engines with 1" diameter output shaft.  This clutch sku doesn't include the drive gear as they are sold separately on our website.

Our Price: $424.00