Watch the marinara the day of a race. The heartburn/indigestion factor can wreck havoc (stress induced asthma is very real) on your time. Go carb heavy tonight (pasta) and stay healthy and light tomorrow (say a bowl of fruit and toast for breakfast) and most importantly drink lots of water. Also, don't fall into the caffeine trap, while it is a stimulant, it is also a diarrhetic (dehydrates you) and that will have a far greater impact. get a good stretch in and be sure to get in a good warm up as well. You should have a sweat going (but not winded or breathing heavy) lined up at the start.