Fast light arrow? Slow Heavy arrow? OR how? I have been woundering this for a while.

The formula for KE is speed x speed x weight / 450240. As you can see, it is directly affected by arrow weight and speed, so, the idea is to get a heavy arrow to fly fast. By shooting a lighter arrow, you will gain more speed, but there is a point where the arrow is too light to gain any KE. The same is true if you shoot a heavy arrow, you will lose speed, but, there is a point where the curve will reach it's apex, and the KE will be at its highest before it starts to drop off again. So, the balance of the two is important.
Another factor to consider: A heavy arrow will have more momentum, which some ppl believe is even better than KE. A light arrow will lose momentum (slow down) much faster than will a heavier arrow. So, the heavier arrow will have more downrange momentum, which is a good thing.
I downloaded Easton's arrow chart, they have a KE calculator, so, if you know how much any given arrow weighs, and the speed your bow shoots it, (or at least a good guess), you can play with the numbers to get the happy medium you are looking for. Wow, I think I confused myself......hope this helps.

Fast heavy arrow.

Light or heavy, the weight of the arrow won't have much effect on the initial kinetic energy that any given bow will put out. The three things that will give you the most bang for the buck in the KE department are: 1 - buy a bow with high IBO rating, 2 - crank up the draw weight, and 3 - stretch your arms so your draw length will be longer.

I am a slower Heavy arrow shooter.
I have never failed to get a complete pass thru .
Also I found that this set up is a little more forgiving than a fast light arrow.

Johch

To max out KE you would have to shoot what most would consider a light arrow. Momentum is what matters, KE means absolutely nothing. A .22 can have 156Ft Lbs of energy, and shooting a deer in the vitals will most likely not kill a deer. I will even say this, if you are shooting 300+ Fps you are not shooting a heavy enough arrow, you are sacrificing momentum for speed which is in my opinion dumb but thats just my honest opinion. Momentum is what matters.

so ke dont matter it is momentum?

Methinks Mr. Olink be very facetious! (At least I hope)

... unless you're shooting a Bowtech Allegiance which I think some people on here will say has plenty of momentum and still can hit 300+ fps.

Is 400 grains at 300fps dumb? I think it will be just right. Works out to be 80 ft-lbs of Energy and I would say alot of momentum