so i'm headed out for about a century (not sure of the exact distance) on sunday, which is a good bit farther than i've ever gone in a day, and i was wondering what i should be doing about eating beforehand. i know about keeping the calories in while i'm on the road, but how far ahead should i be looking at how i'm eating? i know i should eat a good breakfast, and it can't hurt to have a good pasta meal the evening before, but should i be looking at eating more/differently a few days in advance? thanks!

I have a pasta meal both nights for 2 days previous to my ride, and then I have a bowl of oatmeal for breakfast the day of. Nothing too heavy, just a little more substantial than my average 300 cal/hr intake during the ride.

Have a decent breakfast, make sure you're well hydrated (coffee works a charm for me, your results may vary) and... This is most important... Take plenty of water and sports drink with you, along with more snack stuff than you'll likely eat... and make sure those snacks agree with your digestion. It can be a pain carrying all that stuff, which is why I use a lightweight daypack in cold weather, and a rack & trunk in summer.

My extremely unscientific nutrition for a Saturday morning 110 miler looks like this:

Brecky: Double bowl of bran flakes, bagel with low sugar jelly, banana, o.j., and a root beer mug full of black coffee... Maybe 600 - 650 calories. (About that coffee... I don't drink or smoke, and I haven't used a recreational drug since the Carter administration. Heck, I don't even curse. Nobody takes my coffee away... Nobody.)

Snacky: One Powerbar, one store-brand granola bar, one apple, one single serving cereal box, (Cocoa Puffs!)
one single serving bag of pretzels, one small Lender's raisin bagel. Emergency ration: 1/2 Snickers bar in case I get weird and I'm still ten miles from home. I take two large water bottles, and refill both at least twice along the way. (My company has a satellite office along my typical route... I can use the outside faucet when I go by.)
If it's really hot, or I'm really suffering, I'll stop at a convenience store and buy a 20oz Gatorade... But usually I don't need to.

I'm guessing that this won't work for you... or anybody else. You have to find what works best for you, be it half a dozen gel packs or a big bunch of bananas...

I used to ride with a guy who brought a baggie full of barbecue chicken wings with him. Must've worked, we did several epic rides tigether. I wouldn't have wanted to ride his bike, though... he pretty well greased up the bars & levers with his sticky fingers.

I eat normally on the days before a long ride.

Then I drink an Ensure on the morning of the long ride.

And I aim to consume about 250 calories per hour while I ride.

Don't overeat thinking you are "carbo loading" the night before, that just stays in your digestive tract (or maybe it won't stay, and will want out ;D) it doesn't go into your muscles. As others have said, eat normally, stuff that doesn't upset your stomach. Not too much fat, and try to eat reasonably early and SLEEP as much as you can, that's a big factor.

I eat just my normal cereal & milk breakfast before a big ride - trying to eat big just doesn't work. IF you normally eat a big breakfast that might be a different story.

If you eat well normally there should be no great need to change dramnatically before the event. I'd opt for oatmeal and bananas for breakfast and try to eat little and often during the ride to avoid a defcit inducing bonk.

Cycling Nutrition Advice (http://cycling.dingdangdo.com/nutrition.php)