I stumbled across a possible new place for big block clone engines. I'm not going to post the web link just yet for this site to be sure it is Mower racing worthy, but I have a GX440 clone engine ordered and when it arrives I'll be posting pics during the unboxing. Followed by a teardown to inspect the engine further inside and out. Some details on these engines are: 440cc, 92mm bore by 66mm stroke. 18hp claimed stock out of the box. Engines are sold as long blocks without carburetors, Exhaust, Or fuel tank. They can be purchased in either electric start or pull only. To be race ready these engines will require a billet flywheel, rod, and head work. Balance shaft is included with engine as well to stop the eyeball popping some of these engines can cause. Representative from this company stated that they went to the plant where these are built with pluses and minues of all other clone engines built and made changes to these engines where needed to address clone deficiencies and further strengthen the good points. Engines come from factory with no governor to remove or oil alert sensors to remove(Block castings are blocked in these locations). Spark plug boot looks to be upgraded and coil is supposed to be non rev limiting. Cams offered by this merchant are ground by Tim Iskenderian at small engine cams. They have a few different cam grinds available. upgraded valves, and Billet Rods are offered from Parson's Racing Supply, Along with ARC flywheels and rods. Rockers and other various parts from raceseng are also listed. Base GX440 longblock is $329 for non-electric start and $349 for the electric start version. New stock bare heads are $28.00 so you could buy 2 or 3 heads and work on different porting and valve combo's and be able to test much easier. Here are the supplier sourced tech specs:
These engines are made to our specifications and are the only Straight-shaft 439cc Honda GX390 "big bore clones" available for purchase in the United States. They are EPA-exempt and are currently sold only in longblock form to racers and engine builders of racers.
We maintain positive direct contact with our factory to ensure consistency and the ability to continually improve these engines as time goes on. We appreciate all feedback(positive or negative) and would like to hear from you, regarding what you (the racers) want in these engines.
-92mm Bore x 66mm Stroke
-3 Angle Intake Valve Seat
-36mm Intake & 31mm Exhaust Valves
-32lb HD Valve Springs Factory Installed
-Extra-thick Cylinder Head Deck (41cc Chamber) Can be milled over .150"
-6 Amp Charging Coil
-Uses all GX390 Parts
-Cam journal is NOT 0.008 oversize like most clones
-Lightweight 235gram Connecting Rod
-388gram Piston & Wrist Pin (-7cc Dish)
-Oil Alert and Speed Governor have been removed and holes plugged.
-Balance Shaft included
-All Engines are Test-Run before being shipped.