Help Water Problems

[thisolechevy]

Help I just wrote a forum about how good my truck was running! but I just drove it in the rain and had BIG problems! I need help figuring out what the problem is. I had just washed my truck before it rained and hosed all of the dirt off of the engine, I don't think that I got anything to wet but who knows? and then it rained pretty hard. When I started it it ran pretty rough and the more I went the more it backfired. Well when I got to my destination it just stopped running, about an hour later I went back and poured some in the carb. and it cranked right up and ran GREAT all the way home?? What is up with that? I have upgraded from points to electronic ign. by the flamethrower kit. and have an open element Edelbrock aircleaner with K&N filter
Brad