Stihl MS 660 MAGNUM HOTSAW!! This saw is all original, all OEM and has less than 5 hours total including the final test run time. The saw was completely disassembled, cleaned, and reassembled with new OEM factory Stihl parts, OEM seals, OEM gaskets and OEM rubber hoses where needed (including a new oil hose, pulse line, fuel line, intake hose, air filter, spark plug, and fuel filter) the factory Mahle cylinder was ported with the following measurements. The base has been decked 0.050.
The combustion chamber was reshaped and polished down to acquire a 0.020 squish band. The intake port was widened. 030 on both sides, raised. 040 compensating for cylinder drop after decking, and the bottom of the port window was closed 0.030, again to compensate for the drop of the cylinder after decking. The transfer ports were raised 0.050 and the transfer port runners were expanded 0.030 around the piston side of the runner and 0.100 on the outer side of the runner.
The sides of the transfer ports were also widened 0.040 on both sides and the the ports were rough sanded to reintroduce a small amount of turbulence to better atomize the fuel mixture before entering the cylinder. The exhaust port window was widened 0.030 on both sides and the port window roof and floor were left untouched which results in a drop in the port of 0.050 after the decking process. This produces a longer power stroke and more torque in the cut. The exhaust port was tapered out to an exit which was widened to the max allowed by the casting, and the gasket and muffler entrance were matched. The muffler inner baffle was removed, the exit was doubled in size, and a custom dual buckshot exit was installed.
The ignition timing was advanced 12 degrees. The new rubber intake manifold as well as the plastics surrounding the manifold were trimmed and smoothed to promote better air flow. The carburetor butterfly screws were trimmed back flush to prevent turbulence inside the venturi, and the stock HD automotive style air filter was left stock. Both available inlets for the air box were opened to allow an adequate amount of airflow through the filter under load (in the cut). Finally, the carburetor was retuned and the saw was put through the paces.
The 25 bar is also original (which also shows how many hours are on this unit) and the original chain has just been resharpened. Chainsaws are not a toy and any injury shall be the sole responsibility of the end user. Thank you for your interest! The item "Stihl MS 660 MAGNUM Extreme HOTSAW!
Low Hour" is in sale since Tuesday, June 18, 2019. This item is in the category "Home & Garden\Yard, Garden & Outdoor Living\Outdoor Power Equipment\Chainsaws".The seller is "hollywoods_twostrokes" and is located in Palatka, Florida. This item can be shipped to United States.