if you are generating about 61 ftlbs of energy at the bow then it would be safe to say you might be around 45-50 lbs of KE at 60 yards. a lot variables go into figuring this. The length of fletch, fletch height, shaft diameter, etc.

As far as saying the the heavier arrow has more KE, well it depends. both speed and weight have an affect on KE. a light arrow can have just as much KE as a heavier slower arrow. It is safe to say that the heavier shaft will loose less of it's KE at longer ranges than the lighter shaft. How much of an advantage is this? Really it depends, if we are only talking a few ft. lbs of KE at 40 yards if so I wouldn't worry about it.

your question was "If I shoot a 375 gr carbon & get 61ft/lb of KE is that going to perform worse than a 440 gr arrow with the same KE " - It is safe to say the heavier arrow with the same KE at the bow would have more KE at longer ranges BUT this may be only a few ft. lbs. of KE when you actually figure it out. would I trade the speed for a couple more ft. lbs of KE? no way, unless it was for moose.

good luck. you might also want to check out a pc. of software called the archery program. you can graph any sppeed & Ke stuff you want to for your arrow & bow. It is really cool & you could see what you would gain & loose with each arrow choice you mentioned.