Loud clanking noise

Ever since i bought my car when i would start it up i would here a clanking for the first 5 seconds then it would go away. over time i started to here it any time the engine was between 1500-2500 rpms but it wasnt to loud so i just thought a bracket was loose or something minor. well just the other night i was being really hard on my car florring it everywhere and such, and the noise got really loud really quickly. now i am afraid to drive it. Im gonna check under the valve cover and the timing cover then prolly rebuild the engine. B4 i do all thiss is there any things im forgeting to check. sadly im pretty sure its a rod clanking but any ideas would be great.

Hmm are you sure its an internal engine thing? Heat shields and water pump/ps pumps can make bad noises too

its probably your heat sheild or cat.... your cat could have some off broken aspests rumblin around in ur cat.......

No it is the engine it is louder than any bad cat i have everheard. i have had 2 cars throw rods and it sounds exactly the same as they did right b4 it happened. thanks for the ideas i only wish that was all that is wrong.

make sure you have oil pressure, my car in the morning would somtime take a second to come up with the oil pressure and it would make all kinds of ugly noises.