Relationship Between Air Compressor Motor HP and Pump HP

Pump isn't high enough CFM for the massive tank.

I've been looking into new pumps for this bad boy, but am having troubles understanding the correlation between pump HP and motor HP ratings.

I know that actual HP is hugely inflated from what the marketing team puts on products, but help me understand the below examples:

2HP motor attached to a 3HP pump.
--> In this situation, wouldn't the pump just have a lower RPM than if it were a 3HP motor?


How are the Pump HP calculated? --> The amount for force required to rotate to a particular RPM using a particular flywheel size?



In particular, I am referring of course to my own compressor. It has a massive 240V 2HP motor. Looks to be about 30 years old if I had to guess. For the sake of argument, lets assume it actually is 2 HP

It has a retrofitted "Devilbiss Model 220" (doesn't list the CFM) - I am thinking it is too small for the tank size (~100Gallons). To fill from empty once, the bolt heads showing at the top are hot enough to simmer water. (right now it leaks from a pipe fitting, so I have to fill from empty to use each day)

I'm looking into getting a larger pump, but do not want to step up to a larger pump without first understanding the implications of going too large.


I've done lots of research online, but couldn't find the specific relationship between these two vital components of an air compressor.



My current action plan is to buy a

Last question, is there anything wrong with buying a higher HP pump, and then downsizing the motor side flywheel? (terminology okay there?)


My degree in "I rode a bicycle as a kid" says that a smaller motor side wheel will alleviate the extra work required at the cost of a lower CFM?


After writing all this, I guess it has helped me to summarize my question as:
What is the best way to get more CFM from my existing motor? (This train of thought because upgrading the motor appears to be 2-3 times the cost of upgrading the pump)(also, the pump is clearly an undersized replacement currently on the compressor)

I recently bought an air compressor from my local classifieds. It's been pressure tested and confirmed safe for use. ( Story Pump isn't high enough CFM for the massive tank.I've been looking into new pumps for this bad boy, but am having troubles understanding the correlation between pump HP and motor HP ratings.I know that actual HP is hugely inflated from what the marketing team puts on products, but help me understand the below examples:2HP motor attached to a 3HP pump.--> In this situation, wouldn't the pump just have a lower RPM than if it were a 3HP motor?How are the Pump HP calculated? --> The amount for force required to rotate to a particular RPM using a particular flywheel size?In particular, I am referring of course to my own compressor. It has a massive 240V 2HP motor. Looks to be about 30 years old if I had to guess. For the sake of argument, lets assume it actually is 2 HPIt has a retrofitted "Devilbiss Model 220" (doesn't list the CFM) - I am thinking it is too small for the tank size (~100Gallons). To fill from empty once, the bolt heads showing at the top are hot enough to simmer water. (right now it leaks from a pipe fitting, so I have to fill from empty to use each day)I'm looking into getting a larger pump, but do not want to step up to a larger pump without first understanding the implications of going too large.I've done lots of research online, but couldn't find the specific relationship between these two vital components of an air compressor.My current action plan is to buy a "3hp" pump, or maybe a "5hp" expecting that the actual rating will be lower than what is advertised. Is this correct, or should I trust these (Asian made) ratings?Last question, is there anything wrong with buying a higher HP pump, and then downsizing the motor side flywheel? (terminology okay there?)My degree in "I rode a bicycle as a kid" says that a smaller motor side wheel will alleviate the extra work required at the cost of a lower CFM?After writing all this, I guess it has helped me to summarize my question as:What is the best way to get more CFM from my existing motor? (This train of thought because upgrading the motor appears to be 2-3 times the cost of upgrading the pump)(also, the pump is clearly an undersized replacement currently on the compressor)