knocking and heating up

[playboy1884]

i recently got my evo 3 big 16 put on and now my car when i start it up i hear a knocking sound. Now when it gets hot it goes away , is that because of the fact that my exhaust mani is warped and cracked? and why does my car get hot not hot but warms up under boost..

 

[philipkrotch]

uhhh, ya. i had my mani gasket leak and it made a knocking sound until it heated up.