|Fully ported, flow bench designed, GX390 and GX420
Cylinder Heads available with swirl polish stainless racing
valves and combustion chamber volume of your choice.
|Forged racing piston for standard bore GX390 88mm downsized tool
steel wrist pin to .630" diameter and raised to accomodate new longer
billet rod. Notice valve reliefs pre-cut in piston in proper location.
Piston kit includes forged piston, tool steel wrist pin, piston ring set and
circlips. $225.00 Also available in 90mm
Piston is 35% lighter than stock & wrist pin is 30% lighter than
|Competition exhaust systems, pipes and
mufflers available for the Big Block
|Hard welded lobe race cams available for the
Big Block Clones. This proprietary grind did
not just fall off the turnip truck. Extensive
dyno and on track testing has proven this to
be the winning profile. $225.00
|This dual combo clearly shows the new longer billet rod (4.842) &
raised wrist pin forged piston in comparison to cast aluminum units.
Bolt-in horsepower and reliability.
|H Beam Billet Rod Machined from
Aircraft Quality 7075T6
Aluminum. 4.842. Torque to 21 ft
lbs with oil on the thread.
$199.95 includes bearings and mil
spec rod bolts
rod bolt torque: 21 ft lbs.
|Fits perfectly on your GX390 Clone Blower
Housing. Solid screen for those wanting more
heat in the engine $14.95. Vented Screens for
those wanting to run a cooler engine. $19.95
|Steel billet starter nuts to fit the GX390
& big block Clones. Yellow zinc plated
with 3/4" hex and 5/16" hex. $19.95
|Stainless Valves from Stock Clone to
Huge Jr Dragster valves. Prices range
from $16.00 - $23.50 per valve.
|New GX390 Billet Intake Manifold
with hardware. Fits the Tillotson
HR Series & the HW Avenger
|These cylinder heads
are built personally
|We took an existing 6" billet aluminum
flywheel and re-tapered it to fit the
GX390 crankshaft! Cooling fins included.
|Clements Racing Products
|GX390 Dual Valve Spring Kit
|"New, Clements 390
Outlaw Engine Kit" engine
without all those parts engine
without all those parts you
Introductory Price: $199.95
Also, we carry a full line of billet
components to build these into
complete Thunder Maker
This engine appears orange in
the picture, it is actually a