Maybe start by describing what you're currently doing.

Start with this question:
"What am I certain of right now?

Then this question:
"What I think is going wrong is..."

What I am certain of is that my of top 4 contenders 1 is winning 78% of the time . What I think is going wrong is that I am unable to narrow them to one or two contenders some are won by class or early pace combining low and high neal so I need some help narrowing down the contenders to the winners

Ira- I too have encountered the same question. My problem is more related to horizontal wagers than exacta plays. Assuming a 78% win one four contenders I would hit less than 40% OF PICK 4 plays.
My solution has been to key races in a sequence to one or two contenders and playing all contenders in the other races. This has resulted in careful ticket writing to show a rather small profit.
If I was focusing on exactas I would look for races where I was comfortable keying on one or two horses as winner while dutching others to place in exactas. Does your record keeping tell you how many times the win/place are part of your contenders? I'm impressed with your contender selection process but we are fighting to insure capturing the place horse. Please keep me posted on your progress

What I am certain of is that my of top 4 contenders 1 is winning 78% of the time . What I think is going wrong is that I am unable to narrow them to one or two contenders some are won by class or early pace combining low and high neal so I need some help narrowing down the contenders to the winners — Ira Yorn

Examine the two questions again.

Being certain of an END RESULT is a good start. But the answer must be framed in the manner of "I am certain that doing THIS, AND THIS will get me 78% winners WITHIN MY TARGET RANGE OF HORSES."

I'll explain why...
Let's say that you are using the AI Line's top 88% to pick contenders.
(That will likely score you about 91% wins.)

However, it logically will often include 6 or 7 horses. So, in those cases it tells you nothing.

78% is a very good number... if it is usually no more than 3/4 horses. Beyond that, it isn't doing anything for you. That is, if it isn't scoring you the horses you are searching for.
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I would think that the problem needs to be BETTER DEFINED.

Think of it like going through a grocery store. Imagine there are aisles containing handicapping approaches.


**High Hit Rate
They usually don't label "but Low Prices" because the high hit rate/low prices are dating on a regular basis.

**High Prices
"Low Hit Rate" can be assumed, right?
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Reconsider the question "What I think is going wrong is..."
What do you think the CAUSE of this is?

Also, @Tony Kofalt gave you his answer.

Notice how his answer included a STRATEGY for addressing the problem.

That is probably what you're looking for...

What strategy are you currently using to get the odds ranges you're looking for?

Tony
Thanks a lot I really appreciate it `Maybe we can meet sometime and discuss this more