Guys...you are gonna confuse the shit out of the new guys, let's get some stuff straight.
It doesn't matter if a centrifugal vacuum/blower is 2 stage or three stage, each "stage" is responsible for X amount of compression of atmosphere (lift) and X amount of airflow generated (cfm), the larger the armature and the greater the amperage avail. the better the vac motor is to compress those stages against resistance, and support that lift against resistance. The larger the actual blades are and the design of turbines themselves, the greater the amount of CFM is generated with each revolution of those blades, larger blades require more amperage as does high lift, it's really that simple.
So...in economy priced vacs you generally see either a high cfm rating at a given amperage OR a high lift rating, and it's easy to make a 2 stage spin up and provide high cfm without a load, but it takes the addiional staging of a three stage and additional amperage to generate the compression needed for higher waterlift, you can't cheat mother watts.
The most efficient and generally more expensive centrifugal vacs will have high CFM and higher lift, but you most defintely get what you pay for, and not all vacs are created equal.
It's real easy to have a flashy high number for marketing purposes, but truth is what good is a 120 cfm vac if it drops to 50 cfm under real world load?
There are limits to how many vacs you would bother stacking in a base unit, and that answer is heavily determined by the hose diameter and length you would be running with said unit, if you want to run over 100' with any elec. unit, you would be well placed to put your dollars into a stand alone inline vacuum booster closer to the wand, it'll give you BACK some of the airflow and lift you've lost via mother gravity and friction, you'll never hit pie in the sky numbers on 150'-200' of hose but the booster will give you BACK your vacuum that you started with, and at the end of the day, that is all we can ask.
It's the very reason the M-5 is only a 230cfm machine, and not a 400cfm machine, I don't need the marketing numbers, I need the performance of the 146" of water lift coupled with a real 200+ cfm at the wand, that is where the magic happens with a 2" glided wand, any porty Mfg. selling a high performance unit without a glided 2" wand is fully missing the boat.
It doesn't matter if a centrifugal vacuum/blower is 2 stage or three stage, each "stage" is responsible for X amount of compression of atmosphere (lift) and X amount of airflow generated (cfm), the larger the armature and the greater the amperage avail. the better the vac motor is to compress those stages against resistance, and support that lift against resistance. The larger the actual blades are and the design of turbines themselves, the greater the amount of CFM is generated with each revolution of those blades, larger blades require more amperage as does high lift, it's really that simple.
So...in economy priced vacs you generally see either a high cfm rating at a given amperage OR a high lift rating, and it's easy to make a 2 stage spin up and provide high cfm without a load, but it takes the addiional staging of a three stage and additional amperage to generate the compression needed for higher waterlift, you can't cheat mother watts.
The most efficient and generally more expensive centrifugal vacs will have high CFM and higher lift, but you most defintely get what you pay for, and not all vacs are created equal.
It's real easy to have a flashy high number for marketing purposes, but truth is what good is a 120 cfm vac if it drops to 50 cfm under real world load?
There are limits to how many vacs you would bother stacking in a base unit, and that answer is heavily determined by the hose diameter and length you would be running with said unit, if you want to run over 100' with any elec. unit, you would be well placed to put your dollars into a stand alone inline vacuum booster closer to the wand, it'll give you BACK some of the airflow and lift you've lost via mother gravity and friction, you'll never hit pie in the sky numbers on 150'-200' of hose but the booster will give you BACK your vacuum that you started with, and at the end of the day, that is all we can ask.
It's the very reason the M-5 is only a 230cfm machine, and not a 400cfm machine, I don't need the marketing numbers, I need the performance of the 146" of water lift coupled with a real 200+ cfm at the wand, that is where the magic happens with a 2" glided wand, any porty Mfg. selling a high performance unit without a glided 2" wand is fully missing the boat.
