My suggestion would be to sharpen the blades and keep the deck clean. Making the blades rotate faster than they were engineered for is a safety issue and a probable quality of cut issue also. By creating excessive air flow that your deck is not designed for will most likely lay the grass down before the blades come in contact with it, ultimately leaving a ragged cut.
Properly sharpened and balanced blades. Engine ran at Wide Open Throttle. Only go as fast as the mower can go and still manage a clean cut.
If you want a faster mower, then you need to invest into a premium commercial mower.
Craftsman 4000 DYT: with blades really sharp and at a medium
idle (about 900 rpm) land speed about 4 mph....the engine is
fairly quiet and you cannot tell if the mower deck is even running
save for the clippings being discharged from the chute.
Ariens I think it had a 28 inch deck ....single blade ..... engine running
about 800rpm quiet engine and mower very quiet .....Neighbor
next door thought I had an electric .....
Weedeater One ......Engine Running fairly quiet.....Until I engaged the mower
deck ....Wow Like an airplane taking off ....Like clear the runway for take off !
Just a good sharp blade running at medium speed and police the area of harmful
foreign objects especially like pop cansfrom drive by's !
