JDMV35

i noticed it only happens when the engine is cold so im guessing it would be more likely exhaust because once the car is warm is goes

Here is the vid also IMG_1753.MOV

Hi, guys i have just acquired a Nissan v35 skyline coupe and i bloody love it. One thing that has got me startled is that when i start the car it has a knock that only occurs once like a "thud" coming from where the manual gear stick is under the car. It occurs once the car turns over and only when it is cold any ideas? (I hope i didn't buy a lemon) Ill put up a video in a bit. P.S i did a search for this and apparently this has occur ed on another skyline in perth but there were no answers for it on that thread the user i think was sleekr33 or something Cheers.