I know this has been discussed before but what angle to the 1-3 pocket seems to get the most strikes? Would it be down and in.....up the boards.....or the inside swing shot which a lot off balls already have that angularity built into them?

I will retract my second statement and agree with Tdub that no not the earliest but definitely earlier than most of these skid/flip reactions that most people are looking for.

I would tend to believe that ball speed is as important as anything...

I find this statement interesting because one of the first things my friend said in trying to justify his position was...I have to be more consistent with my ball speed!

However....i believe your ball speed will fluctuate greatly as you attempt to find that sweet spot in your swing when changing balls. It is inevitable.

It has to do with rotational value or integrity...difference between flare out vs roll out.

Care to go more into this or have a link that does??

Here's something that might have what your looking for

http://wiki.bowlingchat.net/wiki/images/8/8d/PinCarryStudy.pdf

Ball motion phases

http://wiki.bowlingchat.net/wiki/index.php?title=Three_Phases_of_Ball_Motion

^^^^^^
Nice job!

Eons ago the then A B C decided that an angel of 2 degrees was the best angle to carry strikes. They determined this by rolling a ball down a fixed ramp. However there are so many variables such as speed, rotation, lane and ball surface, weight etc. that this didn't really prove anything. Condition of the pins and their weight also have an effect.
Sooooo  the best angle is the one that works for you at that particular time. And that could change at any moment.

Entry angle per se is the most over rated, and mis understood variable in bowling.  The only way to carry consistently on anything other than a dead flush high pocket hit is to minimize ( not eliminate, but minimize ) deflection off the head pin. 

What people do not understand is that increased entry angle in and of itself does not decrease deflection, but only changes the direction of deflection.  What minimizes deflection is the release of rotational energy regardless of entry angle. 

The reason entry angle became so ingrained is that prior to the super hard surfaces, and the aggressive shelled balls, there was a high correlation between the amount of hook, and the release of rotational energy.  That relationship is no longer so close today.  The reason is that balls will roll out so quickly after leaving the skid stage.

If you want a real life demonstration of what I am talking about watch any PBA telecast since they have gone to longer oil.  All of the guys have gone to more end over end ( less axis rotation ) causing them to play much straighter, but their carry has not dropped at all.  Indeed on the super long Badger pattern even low rev guys could play relatively straight ( we use to call it fall back ) at 4th arrow and still drive the 5 out on half pocket hits.  The reason is that if they match ball speed to rev rate, the ball is still releasing energy at the optimal place, resisting deflection, even at shallow entry angles.