RSS Excerpts — One for Front page, one for Feeds?

Please bear with me, this may sound a tad confusing, but here we go:

I have a blog where I use the “optional hand-crafted summaries” option to put a one-liner summary of the article (along with the article title) on the front page. That’s all that shows up on the front page, just the title and the summary. What I want to do is, have this one-liner summary show up on the front page, but not show up on the RSS feeds. I.e. I want the article’s first 160 words to show up on the feed instead of the one-liner, which is currently the default. (I’ve since learned how to hack the excerpt to change it from the default 55 words to 160, so that’s not an issue).

I know, kind of confusing. Let me try it again:

On the front page, I want my “optional hand-crafted summaries” to show up, but on the feed, I want the first 160 words. I need to do this so I can submit my feed to a directory, which requires that I have the first 160 words in my articles, and not just the one-liner summary. Obviously, with just the “optional hand-crafted summaries” showing up, it’s not going to work. I could easily fix this by removing the “optional hand-crafted summaries”, but I’d like to find another way to keep/do both if that’s possible.

Is there any way to accomplish this?