I just think if it was the manifold there would be alot of posts about the subject , im very anal about my cars and this is one thing thst is really bugging me!!

 

I know you said you checked it but I had the exact same problem in my car once it got to operating tempetures I looked everywhere thinking for sure it was coming from my manifold or exhaust somewhere after overlooking it probably 100 times it turned out to be my waste gate dump tube vibrating on the frame. When I would look under the car it wasn't touching the frame but once the car got warmed up and the vibration of the motor it would make it touch hopefly this helps.

 

X2 my dump tube did this drove me nuts.

 

Both my dumptubes are good no touching, i for sure know its not my exhaust or anything touching body/frame etc

It will do it even when car is cold or warm

 

next step i guess is to pull the tranny and start the car with just flywheel on it see if it still does it

 

Manifold / exhaust touching imo.

 

Are you sure it't not just the common clutch buzz?

 

if clutch buzz vibrates the whole car then maybe so, but it doesnt matter if clutch is in/out or im driving car at 2k its there


manifold/dumptubes/downpipe are not touching any part of the car

 

If it does it even with the clutch in and there is nothing touching then it's the harmonics of the tubular manifold.

 

i just cant see it being that bad and really only at that rpm, and other people with exact same manifold are not having the same issue, which i would think if it was manifold everyone with it would see same thing

im just worried its going to crack the manifold fast