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CYLINDER HEADS & VALVETRAIN

 

Valve Spring, 35lbs
Code: 12400
Price: $10.50
Available for delivery
Quantity in Basket: none
The 32lb valve springs. Recommended for mild motors using stock cam. Change quantity to two if you want two springs.

Valve Spring, 55lbs
Code: 12420
Price: $10.50
Available for delivery
Quantity in Basket: none
55lb single spring. Install height 1.200" with 90 to 95lbs open pressure. Use with mild cams. Do not use on stock cams. Change quantity to two if you want two springs.

Valve Spring, Dual, 50lb
Code: 12410
Price: $15.00
Available for delivery
Quantity in Basket: none
Dual valve spring for high output motors. Install height 1.300" with 50lb seat pressure. 120lbs open pressure. Coil bind at .600". Change quantity to two if you want two outer and two inner springs.

Shim, .029"
Code: 14370
Price: $1.15
Available for delivery
Quantity in Basket: none
Use these shims under the valve spring to obtain proper install height.

Retainer for Exhaust Valve, 390
Code: 20180
Price: $5.00
Available for delivery
Quantity in Basket: none
Stock exhaust valve retainer. Use on stock intake valve to accomodate lash cap.

Retainer & Keeper Set, 390
Code: 16370
Price: $32.00
Available for delivery
Quantity in Basket: none
This retainer and keeper set is designed to be used with our stainless steel 390 valves. Will not work with stock valves.

31mm Valve, Stainless Steel, GX390
Code: 16310
Price: $32.50
Sorry, we are currently sold out of '31mm Valve, Stainless Steel, GX390'. Please check back later.
Quantity in Basket: none
Stock size head for GX390 exhaust. Stainless steel, nitride coated with hardened tip. No lash caps necessary. Length is 3.642" to accomodate large lift cams. Shim up rocker arms when using these valves. Must use our retainer/keepers set. We may ship our 31mm valves without nitride coating depending on stock available.

33mm Valve, Stainless Steel, GX390
Code: 16320
Price: $32.50
Available for delivery
Quantity in Basket: none
Head size 2mm over for GX390 exhaust. Works on stock valve seat. Stainless steel, nitride coated with hardened tip. No lash caps necessary. Length is 3.642" to accomodate large lift cams. Shim up rocker arms when using these valves. Must use our retainer/keepers set.

35mm Valve, Stainless Steel, GX390
Code: 16330
Price: $32.50
Sorry, we are currently sold out of '35mm Valve, Stainless Steel, GX390'. Please check back later.
Quantity in Basket: none
Stock size head for GX390 intake. Stainless steel, nitride coated with hardened tip. No lash caps necessary. Length is 3.642" to accomodate large lift cams. Shim up rocker arms when using these valves. Must use our retainer/keepers set.

36mm Valve, Stainless Steel, GX390
Code: 16340
Price: $32.50
Sorry, we are currently sold out of '36mm Valve, Stainless Steel, GX390'. Please check back later.
Quantity in Basket: none
36mm valve 1mm oversize for GX390 intake. Works on stock valve seat. Stainless steel with hardened tip. No lash caps necessary. Length is 3.642" to accomodate large lift cams. Shim up rocker arms when using these valves. Must use our retainer/keepers set.

38mm Valve, Stainless Steel, GX390
Code: 16350
Price: $32.50
Sorry, we are currently sold out of '38mm Valve, Stainless Steel, GX390'. Please check back later.
Quantity in Basket: none
38mm valve we use in our big valve cylinder heads. Requires larger seat. Stainless steel, nitride coated with hardened tip. No lash caps necessary. Length is 3.642" to accomodate large lift cams. Shim up rocker arms when using these valves. Must use our retainer/keepers set.

Valve Seat for 38mm Valve, GX390
Code: 16410
Price: $10.00
Available for delivery
Quantity in Basket: none
This valve seat replaces the stock intake valve seat. Use the 38mm intake valve with this seat.

Valve Lash Caps, 390, OEM Honda
Code: 20620
Price: $10.00
Available for delivery
Quantity in Basket: none
Lash caps help prevent valve wear. They also provide a larger surface area for the rocker arm. Use with stock exhaust retainers on both stock valves. Price includes two lash caps. OEM Honda lash caps.

Chromoly Push Rods, 390
Code: 16170
Price: $30.00
Available for delivery
Quantity in Basket: none
Chrome moly push rods are highly recommended when using an AGK racing cam.

Chromoly Pushrods Unassembled, 390
Code: 16180
Price: $30.00
Sorry, we are currently sold out of 'Chromoly Pushrods Unassembled, 390'. Please check back later.
Quantity in Basket: none
Cut to size chrome moly pushrods. Full size assembled length is 6.680".

Guide Plate, Push Rod
Code: 14360
Price: $12.00
Sorry, we are currently sold out of 'Guide Plate, Push Rod'. Please check back later.
Quantity in Basket: none
Use this laser cut guide plate to accommodate our chrome moly pushrods. Also use with our 1.3 ratio rocker arms. Not required when using our roller rockers.

Rev Roller Rockers, 390
Code: 16230
Price: $215.00
Available for delivery
Quantity in Basket: none
Honda (or clone) GX340/GX390 billet roller rocker arms designed and engineered to withstand the valvetrain stress of a modified motor.
  • dyno tested and race proven
  • ratio rockers choose 1.2 or 1.3
  • rocker arm CNC machined from 7000 series alloy
  • low rotational inertia mass due to super light arm design
  • bearing grade brass bushings reduce rotational friction
  • precision ground and hardened roller tip provides ultra smooth rotation
  • ground and hardened alloy steel rocker shaft design eliminates valve train deflection
  • cupped lash adjusters with ARP 12 point fastener

Cylinder Head, 390, Ported & Milled
Code: 16130
Price: $178.00
Sorry, we are currently sold out of 'Cylinder Head, 390, Ported & Milled'. Please check back later.
Quantity in Basket: none
Cylinder head ported and milled. Increased flow and velocity from our porting makes this head an excellent choice for performance and value. Highly recommended performance upgrade for the racer looking to take his/her GX340/GX390 to the next level.

Head Dowel, GX390
Code: 24240
Price: $2.25
Available for delivery
Quantity in Basket: none
Head dowel for the Honda GX390. Price is for one dowel. Change quantity if you want more than one.

Lifter, Stock GX390
Code: 20560
Price: $11.00
Available for delivery
Quantity in Basket: none
Genuine Honda GX390 lifter. Big block motors in the 50hp range are wearing out the stock clone lifters. Use this genuine Honda lifter as a replacement. Sold individually. Change quantity to 2 if you want 2.

Gasket Set, GX390
Code: 20160
Price: $26.00
Sorry, we are currently sold out of 'Gasket Set, GX390'. Please check back later.
Quantity in Basket: none
Engine gaskets set for GX390. Includes head, side cover, valve cover, exhaust and both intake gaskets.

Gasket, Cylinder Head, GX390
Code: 20380
Price: $12.00
Available for delivery
Quantity in Basket: none
Cylinder head gasket for GX390.

Gasket, Cylinder Head, Steel, GX390
Code: 20390
Price: $15.00
Available for delivery
Quantity in Basket: none
Special steel cylinder head gasket. Use with high compression engines. Gasket is .050" thick.