The Candlepower v. Lumens has been discussed many times here.
The great thing about CPF is that if you ask for comparisons between two lights, someone is bound to have them and will reply.
Bulb Wattage and the number and type of batteries is a good way to guess the ballpark.
In general, I take the Lumen value to mean the total amount of light output and the candlepower to be the value of the most intense part of the beam.
The way Lumens is measured is very scientific. I get the impression that Candlepowers rating are based more on marketing hype.
Which flashlights would you like to compare?
Al