I can't figure what kind of engine I have. The dude I bought my Blazer from said it had a new motor in it, I doubt this as it smokes a little when it's cold and leaks quite a bit. Said it was a 350 but I figure I get about 5 or 6 mpg in the city, and think I should be getting better. Engine looks more like the big block picture in my shop manual than the small block picture. I can't seem to find the casting numbers on the block. Thanks for any help.