I'm not sure if this is what you're looking for, but try this (it's really easy):
Homepage Excerpts Plugin
Install this plugin, then at Settings -> Homepage Excerpts you can define how many words to show on the homepage for each post before reaching the "read more" link.
This will then show the number of words of each post you specify on the homepage.
You can choose the number of "excerpts" to show on your home page at Settings -> Reading -> "Blog pages show at most"
I hope this helps but I'm sorry if I misunderstood you.