I like many consumers have been confused when looking to buy a leaf blower on how to find out it's blowing strength. There are many specifications that are thrown on the boxes and shelf discriptions, and if you are unsure of the meaning of the acronyms, may cause you to make the wrong purchase.
There are three prevalent indications on gas powered leaf blowers that are an indication of it's blowing strength. First is CFM, this term designates cubic feet per minute, 375 CFM means that every minute 375 cubic feet of air volume is pushed through the end of the nozzle. Second is MPH, this designates the speed in which the air excapes the end of the nozzle. Third, CC designates the engine size in cubic centimeters. In general, the larger the size the heavier the machine will be. And lastly,db which stands for decibles of sound at 50 feet per ANSI mesureing regulations. The higher the db, the louder the sound the machine will emit.
I have purchased two machines, and found that my initial reaction was incorrect. I looked for the highest MPH thinking the faster the air-speed, the better the blowing capacity. I found that over time, as leaves accumulated, i had a hard time moving them. When i purchaced my second blower, it was about 15-20 MPH less then the first, but almost doubled the CFM of the first blower. This was much more productive as it pushed a greater quantity of leaves in about half of the time because of the volume of air "pushing" the leaves. The tube on the first blower was smaller in diameter, causing the air to exit at a faster velocity, which ment nothing when it was not moving enough air to blow the leaves.
The motor on the second blower was larger by about 4CC's, and of course made it slightly heavier, but i was blowing my leaves in about half of the time and the wieght was not a factor. The decible rating on the second blower was actually lower then the first smaller engine which i find comes from the higher quality motor components then the first lower cost blower.
In short, buy the blower with the highest CFM your budget (and yard size) dictates. Don't be fooled by the high MPH ratings the more inexpensive blowers advertise. I fell into the trap and am now a "proud" owner of two blowers.
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