so this has happened before, but i never really worried about it. just thought I'd see if anyone else has it. when i do a hard launch, i get a kind of clunking, grinding noise. I'm am fairly certain it is from the drive train. I can't decide if it is the rear diff that is slipping or the center diff trying to lock up. Seems like i remember hearing it in my old '00 RS too, so I'm leaning toward rear diff. anyone?
make sure your jack in your trunk is secure..i kept hearing a thunk in my car also till i tightened it down..hopefully this will be the problem versus something mechanical
Also it could be your rear diff floating on you. You get more of a bang noise though between 1st and second. There are bushings you can install to fix that. Hard to say with out hearing the noise.
I don't know... it only happens when launching from a dead stop in first gear. It definately sounds mechanical and not something just loose. It is a grind, but not like when you miss a shift...more like....well... you know if you accidently leave the center diff on lock and try to make a low speed turn (pulling into a parking space) and the rear diff will pop. It's like that only not as intense sounding and in multiple succession, not just once.