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Head Gasket Fits 420cc Big Block Engine Head Gasket Fits 420cc Big Block Engine

This head gasket will fit the Predator 420cc and many other 420cc big block clone engines.

Our Price: $12.95
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: $21.95
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: $21.95
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: $44.95
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: $49.95
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: $64.95